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DEPARTMENT OF LABOR Occupational Safety and Health Administration 29 CFR Part 1910 [Docket No. H-371] RIN 1218-AB46 Occupational Exposure to Tuberculosis AGENCY:
Occupational Safety and Health Administration (OSHA), Labor ACTION:
Proposed rule and notice of public hearing. SUMMARY:
The Occupational Safety and Health Administration is proposing a health
standard, to be promulgated under section 6(b) of the Occupational Safety and
Health Act of 1970, 29 U.S.C. 655, to control occupational exposure to
tuberculosis (TB). TB is a communicable, potentially lethal disease that
afflicts the most vulnerable members of our society: the poor, the sick, the
aged, and the homeless. As many as 13 million U.S. adults are presently
believed to be infected with TB; over time, more than 1 million of these individuals
may develop active TB disease and transmit the infection to others. TB
remains a major health problem with 22,813 active cases reported in the U.S.
in 1995. A number of outbreaks of this disease have occurred among workers in
health care settings, as well as other work settings, in recent years. To add
to the seriousness of the problem, some of these outbreaks have involved the
transmission of multidrug-resistant strains of Mycobacterium tuberculosis,
which are often fatal. Although it is the responsibility of the U.S. Public
Health Service to address the problem of tuberculosis in the general U.S.
population, OSHA is solely responsible for protecting the health of workers
exposed to TB as a result of their job. OSHA
estimates that more than 5 million U.S. workers are exposed to TB in the
course of their work: in hospitals, homeless shelters, nursing homes, and
other work settings. Because active TB is endemic in many U.S. populations,
including groups in both urban and rural areas, workers who come into contact
with diseased individuals are at risk of contracting the disease themselves. The
risk confronting these workers as a result of their contact with TB-infected
individuals may be as high as 10 times the risk to the general population. Although
the number of reported cases of active TB has slowly begun to decline after a
resurgence between 1985-1992, 16 states reported an increase in the number of
TB cases in 1995, compared with 1994. Based on a review of the data, OSHA has
preliminarily concluded that workers in hospitals, nursing homes, hospices,
correctional facilities, homeless shelters, and certain other work settings
are at significant risk of incurring TB infection while caring for their
patients and clients or performing certain procedures. To reduce this
occupational risk, OSHA is proposing a standard that would require employers
to protect TB-exposed employees by means of infection prevention and control
measures that have been demonstrated to be highly effective in reducing or
eliminating job related TB infections. These measures include the use of
respirators when performing certain high hazard procedures on infectious
individuals, procedures for the early identification and treatment of TB
infection, isolation of individuals with infectious TB in rooms designed to
protect those in the vicinity of the room from contact with the
microorganisms causing TB, and medical follow-up for occupationally exposed
workers who become infected. OSHA has preliminarily determined that the
engineering, work practice, and administrative controls, respiratory
protection, training, medical surveillance, and other provisions of the
proposed standard are technologically and economically feasible for
facilities in all affected industries. DATES:
Written comments on the proposed standard must be postmarked on or before
December 16, 1997 and notices of intention to appear at the informal
rulemaking hearings must be postmarked on or before December 16, 1997. Parties
requesting more than 10 minutes for their presentation at the hearings and
parties submitting documentary evidence at the hearing must submit the full
text of their testimony and all documentary evidence no later than December
31, 1997. The
informal public hearings will begin at 10:00 a.m. on the first day of hearing
and at 9:00 a.m. on each succeeding day. The informal public hearings will be
held in Washington, D.C. and are scheduled to begin on February 3, 1998. ADDRESSES:
Hearings will be held in the Auditorium of the U.S. Department of Labor
(Frances Perkins Building), 200 Constitution Avenue, NW, Washington, D.C.
Subsequent additional informal public hearings will be held in other U.S.
locations. A Federal Register notice will be issued upon determination
of the locations and dates of these hearings. Comments
on the proposed standard, Notices of Intention to Appear at the informal
public hearings, testimony, and documentary evidence are to be submitted in
quadruplicate to the Docket Officer, Docket No. H-371, Room N-2625, U.S.
Department of Labor, 200 Constitution Ave., NW, Washington, DC 20210,
telephone (202) 219-7894. Comments of 10 pages or fewer may be transmitted by
fax to (202) 219-5046, provided the original and three copies are sent to the
Docket Officer thereafter. The hours of operation of the Docket Office are
10:00 a.m. until 4:00 p.m. Written
comments, Notices of Intention to Appear at the informal rulemaking hearings,
testimony, documentary evidence for the hearings, and all other material
related to the development of this proposed standard will be available for
inspection and copying in the Docket Office, Room N-2625, at the above
address. FOR FURTHER INFORMATION CONTACT: Bonnie Friedman, Office of Information and
Consumer Affairs, Occupational Safety and Health Administration, Room N-3647,
U.S. Department of Labor, 200 Constitution Ave., NW, Washington, DC 20210,
Telephone (202) 219-8148, FAX (202) 219-5986. SUPPLEMENTARY INFORMATION: Table of Contents
References
to the rulemaking record are in the text of the preamble. References are
given as "Ex." followed by a number to designate the reference in
the docket. For example, "Ex. 1" means exhibit 1 in the Docket
H-371. This document is a copy of the petition for a permanent standard filed
by the Labor Coalition to Fight TB in the Workplace on August 25, 1993. A
list of the exhibits and copies of the exhibits are available in the OSHA
Docket Office. I. Introduction The
preamble to the Proposed Standard for Occupational Exposure to Tuberculosis
discusses the events leading to the development of the proposed standard, the
health effects of exposure to tuberculosis, and the degree and significance
of the risk. An analysis of the technological and economic feasibility of the
proposal and an explanation of the rationale supporting the specific
provisions of the proposed standard are also included. Public
comment on all matters discussed in this notice and all other relevant issues
is requested for the purpose of assisting OSHA in the development of a new
standard for occupational exposure to tuberculosis. A. Issues OSHA
requests comment on all relevant issues discussed in this preamble, including
the health effects, risk assessment, significance of risk determination,
technological and economic feasibility and requirements that should be
included in the final standard. OSHA is especially interested in responses, supported
by evidence and reasons, to the following questions. This list is provided to
assist persons in formulating comments, but is not intended to be all
inclusive or to indicate that participants need to respond to all issues or
follow this format. Please give reasons for your answers and provide data
when available. Specific
issues of concern to OSHA are the following: Health
Effects 1.
What, if any, additional studies or case reports on TB should be included in
the health effects analysis? 2.
Is there information that will provide data for estimating the rise in
Multidrug-resistant TB (MDR-TB)? Is the rise in MDR-TB a serious threat? Risk
Assessment 1.
Are there alternative risk assessment methodologies available? What are they?
Are there other studies available that would be useful for assessing risk? 2.
Are there factors other than or in addition to the ones OSHA has chosen that
would be useful in estimating the background risk for TB? Technological
and Economic Feasibility 1.
Are OSHA's estimates of the numbers and types of workers currently exposed to
M. tuberculosis reasonable? If not, please provide estimates of the
number of workers currently at risk and the percentage of the total workforce
these workers represent, by industry. 2.
Are OSHA's estimates of controlled access rates (i.e., the percentage of
workers currently at risk who would remain at risk after employers minimize
the number of workers exposed to individuals with suspected or confirmed
infectious TB) reasonable? If the number of workers exposed to individuals
with suspected or confirmed infectious TB is minimized, by what percentage
could the number of workers at risk be reduced in each affected industry? In
each industry, what are the job categories that would continue to be
occupationally exposed? 3.
Are OSHA's estimates of the numbers of affected establishments reasonable? If
not, please provide estimates of the number of affected establishments, by
industry. 4.
Are OSHA's estimates of occupational and job turnover rates reasonable? If
not, please provide estimates of turnover rates for each of the affected
industries. 5.
Under what conditions would social work, social welfare services, teaching,
law enforcement or legal services need to be provided to individuals
identified as having suspected or confirmed infectious TB? What, if any,
procedures could not be postponed until such individuals are determined to be
noninfectious? How many workers in each of these categories may need to have
contact with individuals with suspected or confirmed infectious TB under
these conditions? 6.
Using the proposed definition of "suspected infectious TB," how
many individuals with suspected infectious TB are likely to be encountered
for every confirmed infectious TB case in each of the covered industries? 7.
Are OSHA's estimates of the average number of suspected or confirmed
infectious TB cases that would be transferred, per establishment in each
industry, reasonable? If not, on average, how many TB cases per facility in
each of the affected industries would be transferred? 8.
How are individuals with suspected infectious TB transferred to
establishments with AFB isolation facilities? Who pays for the transport of
such cases, particularly for individuals transferred from homeless shelters? OSHA
solicits comment on the feasibility of temporary AFB isolation facilities in
homeless shelters and on methods that could be used to temporarily isolate
individuals with suspected or confirmed infectious TB in homeless shelters. 9.
Of the suspected infectious TB cases referred to hospitals from other
facilities, how many are immediately ruled out without needing to be
isolated? 10.
Are OSHA's estimates of the number of necessary AFB isolation rooms
reasonable? Are existing AFB isolation rooms reasonably accessible to
facilities that transfer individuals with suspected or confirmed infectious
TB? 11.
What types of respirators are currently being used to protect workers against
occupational exposure to M. tuberculosis? 12.
Which of the NIOSH-approved N95 respirators meet all of the proposed
criteria, including fit testing and fit checking criteria? 13.
Are OSHA's estimates of respirator usage rates reasonable? For each of the
covered industries, how often could respirators meeting the proposed
requirements be reused and still maintain proper working condition? How
often, on average, would respirators need to be replaced? Please specify the
type of respirator. 14.
OSHA has assumed, in its Preliminary Economic Analysis, that hospitals will
have licensed health care professionals on-site to perform the medical
procedures that would be required by the proposed rule, and that in the other
industries, employees will have to travel off-site to receive the medical
procedures. Which of the other affected industries typically have licensed
health care professionals on site who could perform the required medical
procedures? If employers were allowed two weeks to provide the medical
procedures, rather than being required to provide them prior to initial
assignment to jobs with occupational exposure, will it be less likely that
employees will have to travel off site to receive these tests/procedures? What
would the costs be if employees travel off-site for these tests/procedures? 15.
Are OSHA's estimates of baseline compliance reasonable? If not, what types of
controls are currently in place to protect workers against occupational
exposure to M. tuberculosis, and what proportion of facilities in each
of the affected industries currently are using such controls? 16.
For facilities that have implemented controls to protect workers against
occupational exposure to M. tuberculosis, how effective have such
controls been in reducing the transmission of TB? 17.
OSHA's Initial Regulatory Flexibility Analysis assesses the impacts of the
proposed standard on small entities using the Small Business Administration's
(SBA) size standards. In
addition, OSHA analyzed the impacts of the proposed standard on entities
employing fewer than 20 workers. Are these definitions appropriate for the
covered industries? If not, how should small entities be defined for each
industry? 18.
The SBA defines small government jurisdictions as "governments of
cities, counties, towns, townships, villages, school districts, or special
districts with populations of less than 50,000." OSHA requests comment
on the number of such small government jurisdictions. 19.
Some parties have suggested that OSHA should allow the use of the CDC
guidelines as an alternative to the proposed rule. However, OSHA believes
that the CDC guidelines are not written in a regulatory format that would
allow OSHA's Compliance Safety and Health Officers (CSHOs) to determine
whether or not an employer is in compliance with the Guidelines. Others have
suggested that OSHA could judge compliance with the guidelines by determining
the number or rate of skin test conversions at the employer's facility. OSHA
does not believe that smaller facilities have an adequate population for
trends in test conversions to have any statistical validity. OSHA welcomes
suggestions on any methods of making the CDC guidelines an enforceable
alternative to an OSHA regulation or methods of measuring performance that
could be applied across all types and sizes of facilities. 20.
Because of the limited availability of data, OSHA characterized the risk in
many sectors as similar to that in hospitals, and less than that documented
in nursing homes and home health care. OSHA welcomes industry-specific data
on test conversion rates or active case rates. 21.
OSHA is unable to determine the effectiveness of specific elements of an
effective infection control program in hospitals. OSHA welcomes any evidence
on the relative effectiveness of individual elements in such programs, such
as the identification and isolation of suspect cases, the use of engineering
controls, the use of respirators, and employee training. 22.
OSHA based its estimate of the effectiveness of infection control programs in
other sectors on studies of the effectiveness of such programs in hospitals. OSHA
welcomes any data concerning the effectiveness of OSHA's proposed infection
prevention measures, or of other alternative infection control measures, in
sectors other than hospitals. 23.
SBREFA Panel members suggested a number of alternative approaches to the
regulation. OSHA believes that it has at least partially adopted a number of
these approaches. OSHA welcomes comments and suggestions on these approaches
and the extent to which OSHA should further adopt them:
24.
OSHA is proposing to include homeless shelters in the Scope of the standard. During
the informal public hearings, OSHA intends to schedule a special session for
participants to present additional information on homeless shelters. Also,
OSHA is conducting a special study of the homeless shelter sector. The
information gathered in the study will be placed in the docket for public
comment. OSHA welcomes comment on any of the topics this study will cover
including: ·
Percentage
of homeless persons that would meet OSHA's definition of a suspected
infectious TB case (A breakdown of which symptoms are particularly common
will help OSHA construct the best definition); ·
Turnover
among the homeless who use shelters; ·
Employee
turnover in homeless shelters; ·
Trends
in the number of homeless persons served in shelters. ·
Criteria
currently used by some homeless shelters to identify suspected infectious TB
cases; ·
Current
practices used in homeless shelters to address TB hazards so that baseline
compliance with the proposed standard can be determined. Of particular
concern to OSHA are: -- Methods of isolation; and -- How suspected TB cases are handled. ·
Feasibility
of hospitals providing cards to the homeless indicating TB skin test status; ·
Number
of TB skin test conversions and active cases among the homeless and homeless
shelter employees; ·
Types
of benefits offered to homeless shelter employees (e.g., health
insurance); ·
Economic
feasibility: -- Costs of running a shelter; -- Revenue sources; -- How costs are accommodated as the number
of homeless persons served increases; and -- Opportunities for cost pass-through; ·
Number,
location and types (e.g., family-oriented, walk-in, all-male) of
homeless shelters; ·
Number
or proportion of homeless shelter workers who are unpaid volunteers; and ·
The
OSH Act applies to employees, not bona fide volunteers. However, OSHA
understands that some states may, as a matter of law, require facilities to
provide volunteers with protections established by OSHA standards. OSHA is
seeking information on: -- Economic impacts in such states of
covering volunteers (e.g., how costs would be handled, cost
pass-through); and -- Protections currently offered to
volunteers. 25.
In what states, if any, do employers provide volunteers in the sectors
affected by this proposed standard with the same protections as they provide
to employees? How many volunteers might be affected by such requirements? 26.
OSHA is concerned that medical removal protection and medical treatment of
active cases of TB may have significant economic impacts on small firms that
have an employee with an active case of TB. Is there any form of insurance
available for covering the costs of medical removal protection or medical
treatments required by the OSHA standard? Should OSHA consider phasing-in
these provisions of the standard? 27.
OSHA believes that substance abuse treatment centers, particularly in-patient
treatment centers, normally have entry procedures that may include medical
examinations. OSHA solicits comments on entry procedures for substance abuse
treatment programs, the extent to which these entry procedures now include
medical examinations, and the extent to which these examinations now include
and examination for TB symptoms. 28.
OSHA requests comment on the effects of extended compliance phase-in dates
for the proposed requirements,particularly for respirators, for small
businesses and facilities relying on charitable and/or Medicare and Medicaid
funding. 29.
OSHA requests comment on all assumptions and estimates used in developing the
Preliminary Economic Analysis. Please provide reasons and data to support
suggested changes to the assumptions and estimates. 30.
The World Health Organization (WHO) has launched an initiative to reduce
active TB through the use of multi-drug therapy and using directly observed
therapy. OSHA solicits comment on whether it should revise its risk
assessment or any of its benefits estimates as a result of this initiative. 31.
OSHA requests comment on the number of affected facilities that are
tribally-operated, by industry. General 1.
A number of provisions in the proposed standard are triggered by the
identification of an individual as having either "suspected infectious
tuberculosis" or "confirmed infectious tuberculosis." Of these
provisions, are there some that should be triggered only once an individual has
been identified as having "confirmed infectious tuberculosis?" If
so, which provisions and why? 2.
A number of the proposed standard's provisions require compliance or
performance on an annual basis, e.g., reviews of the exposure control
plan, the biosafety manual for laboratories, and the respiratory protection
program; certification of biological safety cabinets; fit testing or a
determination of the need for fit testing of respirators; medical histories,
TB skin tests; and training. In addition, certain requirements must be
performed on a semi-annual basis, e.g., inspection and performance
monitoring of engineering controls, verification of air flow direction in
laboratories, and, in some instances, TB skin testing. How can OSHA reduce
the aggregate burden of these requirements, particularly in small entities,
while still providing equal protection to employees? Of these annual and
semi-annual provisions, which, if any, should be performed less frequently? Why
and at what frequency? Which of these provisions, if any, should be performed
more frequently? Why and at what frequency? Scope 1.
Is there information demonstrating risk of TB transmission for employees in
work settings other than those included in the scope? Should OSHA, for
example, expand the scope of this standard to cover all or some offices of
general practitioners or dentists and if so, how? Should OSHA expand the
scope to cover all teachers? 2.
Are there provisions of the standard with which emergency medical services,
home health care, and home-based hospice care employers cannot comply because
their employees are at temporary work settings over which the employer has
little or no control? If so, what are those provisions and why would an
employer be unable to comply with them? 3.
In covering only long-term care facilities for the elderly, is OSHA excluding
similar facilities where there is increased risk of transmission of TB? If
so, what are these facilities? Should OSHA include long-term care populations
in addition to the elderly, such as long-term psychiatric care facilities? If
so, what are these populations? 4.
OSHA is proposing that employers provide medical management and follow-up for
their employees who work in covered work settings, but who are not
occupationally exposed, when they have an exposure incident resulting from an
engineering control failure or similar workplace exposure. Is this the best
way of assuring such employees receive medical management and follow-up? 5.
OSHA is covering employees who have occupational exposure in covered work
settings yet are not employees of the work setting (e.g., physician
employed by another employer with hospital privileges, who is caring for a TB
patient in the hospital). Can this be made more clear? 6.
OSHA has proposed that facilities offering treatment for drug abuse be
covered in the scope of the standard. Is coverage of such facilities
appropriate? What factors unique to facilities that offer treatment for drug
abuse would make compliance with the provisions of this proposed standard infeasible
(e.g., would complying with certain provisions of the standard
compromise the provision of services at facilities that offer treatment for
drug abuse)? Application 1.
OSHA has proposed that an employer covered under the standard (other than an
operator of a laboratory) may claim reduced responsibilities if he or she can
demonstrate that his or her facility or work setting: (1) Does not admit or
provide medical services to individuals with suspected or confirmed
infectious TB; (2) has had no case of confirmed infectious TB in the past 12
months; and (3) is located in a county that, in the past 2 years, has had 0
cases of confirmed infectious TB reported in one year and fewer than 6 cases
of confirmed infectious TB reported in the other year. Are there alternative
methods that can be used to assure protection of employees in areas where
infectious TB has not recently been encountered? Exposure
Control Plan 1.
OSHA has proposed that the employer's exposure control plan contain certain
policies and procedures. What, if any, policies and procedures should be
added to the plan? 2.
The proposed standard requires exposure incidents and skin conversions to be
investigated, but does not require aggregate data regarding employee
conversions to be collected and analyzed. Would the collection and analysis
of aggregate data provide benefits beyond those provided by investigating
each individual exposure incident or conversion? Why or why not? If aggregate
data collection and analysis were required, what type of analysis should be
required, at what analytical endpoint should employer action be required, and
what should that action be? 3.
OSHA has set forth the extent of responsibility for transfer of individuals
based upon the type of work setting where such individuals are encountered. What
are current practices regarding transfer of individuals with suspected or
confirmed infectious TB in the work settings covered by the proposal? Work
Practices and Engineering Controls 1.
Is OSHA's time limit of 5 hours following identification for transferring an
individual with suspected or confirmed infectious TB to another facility or
placing the individual into AFB isolation appropriate? If not, what is the
maximum amount of time that an individual should be permitted to await
transfer or isolation in a facility before the employer must implement the
other provisions of the proposed standard? 2.
OSHA has considered requiring facilities that encounter 6 or more individuals
with confirmed infectious TB within the past 12 months to provide engineering
controls in intake areas where early identification procedures are performed
(e.g., emergency departments, admitting areas). Should this be a
requirement? Are there types of controls, engineering or otherwise, that
would be effective in controlling transmission in intake areas? Would the
trigger of 6 individuals with confirmed infectious TB be appropriate? 3.
Are there methods other than smoke trail testing and continuous monitors that
would be effective for verifying negative pressure in AFB isolation rooms or
areas? 4.
OSHA is requiring engineering controls to be inspected and performance
monitored every 6 months. Is this frequency appropriate? 5.
OSHA is allowing exhaust air from AFB isolation rooms or areas where M.
tuberculosis may be aerosolized that cannot feasibly be discharged
directly outside to be HEPA-filtered and recirculated back into general
ventilation. Is permitting such recirculation appropriate? If used, should
there be any requirements to detect system failure? 6.
OSHA is permitting stand-alone HEPA filter units to be used as a primary
control measure. Is this appropriate? What, if any, methods other than
ventilation and filtration can provide consistent protection? 7.
Should ambulances that have carried an individual with suspected or confirmed
infectious TB be required to be ventilated for a specific period of time or
in a particular way before allowing employees to enter without a respirator? What
engineering controls are available for ambulances? Laboratories 1.
The standard does not require labeling of laboratory specimens. Should OSHA
require that laboratory specimens be labeled within the facility or when
specimens are being shipped? If so, what should the label contain? Are there
other agencies that require these specimens be labeled? What are these
agencies and what is required? 2.
OSHA has attempted to incorporate the CDC/NIH recommendations given in
"Biosafety in Microbiological and Biomedical Laboratories" into the
standard. Do any provisions need to be added in order for employees in
clinical and research laboratories to be fully protected against exposures to
M. tuberculosis? Respirators 1.
OSHA is requiring employees who are transporting an unmasked individual with
suspected or confirmed infectious TB within a facility to wear a respirator. Is
this appropriate? How often would an individual with suspected or confirmed
infectious TB be transported unmasked through a facility? Under what
circumstances would it be infeasible to mask such an individual? What other
precautions should be taken when transporting such an individual who is not
masked? 2.
OSHA is requiring that maintenance personnel use respiratory protection
during maintenance of air systems or equipment that may reasonably be
anticipated to contain aerosolized M. tuberculosis. When would it be
necessary to access such an air system at the time it was carrying air that
may contain aerosolized M. tuberculosis? Should OSHA require that such
air systems be purged and shut down whenever these systems are accessed for
maintenance or other procedures? 3.
OSHA has received information that the use of certain kinds of respirators in
helicopters providing emergency medical services may hamper pilot
communication. Have other air ambulance services encountered this problem? Does
this problem exist when the employee is using a type N95 respirator or other
types of respiratory protection such as powered air purifying respirators? What
other infection control or industrial hygiene practices could be implemented
to minimize employee exposure in these circumstances? 4.
The CDC states that there may be selected settings and circumstances (e.g.,
bronchoscopy on an individual with suspected or confirmed infectious TB or an
autopsy on a deceased individual suspected of having had active TB at the
time of death) where the risk of transmission may be such that increased
respiratory protection such as that provided by a more protective
negative-pressure respirator or a powered air purifying respirator may be
necessary. Are there circumstances where OSHA should require use of a
respirator that is more protective than a type N95 respirator? If so, what
are the circumstances and what type of respiratory protection should be
required? 5.
OSHA is proposing that respirators be fit-tested annually, which is
consistent with general industrial hygiene practice, or, in lieu of an annual
fit test, that employees have their need to receive the annual fit test be
evaluated by the physician or other licensed health care professional, as
appropriate. For the circumstances and conditions regulated by this standard,
will the evaluation provide enough ongoing information about the fit of a
respirator to be an adequate substitute for fit testing? Should OSHA require
that an actual fit test be performed periodically? If so, at what frequency? 6.
OSHA has not included any provisions regarding the use of supplied air
respirators. Are there circumstances in which supplied air respirators would
be used to protect against M. tuberculosis? Should OSHA include
provisions addressing supplied air respirators in the standard? 7.
OSHA is permitting the reuse of disposable respirators provided the
respirator does not exhibit excessive resistance, physical damage, or any
other condition that renders it unsuitable for use. Will the respirators
continue to protect employees throughout the reuse period? 8.
In the proposed standard for TB, OSHA has included separate provisions for
all aspects of a respiratory protection program for tuberculosis. What other
elements might need to be included? Which respiratory protection provisions,
if any, are not appropriate for protection against TB? Please provide reasons
and data to support inclusion or exclusion of particular provisions. Medical
Surveillance 1.
Should any provisions be added to the Medical Surveillance program? 2.
OSHA has not required that physical exams be included as part of the baseline
evaluation. Is there information that is essential to medical surveillance
for TB that can only be learned from a baseline physical exam? 3.
OSHA is specifying tuberculin skin testing frequencies for employees with
negative skin tests. Should tuberculin skin testing be administered more or
less frequently? Are there other ways to determine the frequency of
tuberculin skin testing? 4.
OSHA is proposing that employees entering AFB isolation rooms or areas be
skin tested every 6 months. However, employees providing home health care,
home care, and home-based hospice care are to be skin tested annually. Employees
entering the home of an individual who has suspected or confirmed infectious
TB may have the same potential for exposure to aerosolized M. tuberculosis
as employees who enter an isolation room. In light of this, should employees
providing care to individuals with suspected or confirmed infectious TB in
private homes be skin tested every 6 months? 5.
OSHA is requiring that all tuberculin skin testing be administered, read, and
interpreted by or under the supervision of a physician or other licensed
health care professional, as appropriate, according to current CDC
recommendations. Should OSHA require specific training for individuals who
are administering, reading, and interpreting tuberculin skin tests? If so,
what type of training should be required? 6.
Should OSHA require a declination form for employees who do not wish to
undergo tuberculin skin testing? 7.
OSHA is including Medical Removal Protection (MRP) provisions for employees
who are unable to wear respiratory protection or who contract infectious
tuberculosis. Are there additional provisions that need to be included? What
remedies are available to employees in states where worker compensation
system do not consider occupational TB a compensable disease? What benefits
are provided to workers who are unable to wear a respirator? 8.
OSHA is requiring that employees who must wear a respirator be provided a
face-to-face determination of their ability to wear the respirator. Does this
determination need to be made through a medical evaluation or would the use
of an appropriately designed questionnaire be adequate? What would be the
advantages and disadvantages of relying on a questionnaire to make this
determination? Are there sample questionnaires that have proven to be
effective for determining an employee's ability to wear a respirator? 9.
OSHA has drafted Medical Surveillance, paragraph (g), to explain first who
must be provided with the protections listed in the paragraph and how the
surveillance is to be administered and secondly, in paragraphs (g)(2),
Explanation of Terms, and (g)(3), Application, how the general medical terms
are to be construed to meet the standard and in what instances the medical
examinations or tests are to be offered. The Agency realizes that there is
some repetition in these paragraphs and seeks comment on whether there might
be a better way to list the requirements. Communication
of Hazards and Training 1.
OSHA is requiring that signs for isolation rooms and areas bear a
"STOP" Sign and the legend "No Admittance Without Wearing A
Type N95 or More Protective Respirator." Is there another sign that
would assure patient confidentiality while providing adequate notification of
the hazard and the necessary steps to minimize the hazard for employees who
may be inadvertently exposed? 2.
OSHA is requiring that ducts be labeled "Contaminated Air -- Respiratory
Protection Required." Should OSHA require that duct labels also include
the "STOP" sign? 3.
Is the labeling of ducts carrying air that may contain aerosolized M.
tuberculosis (e.g., from isolation rooms and areas, labs) at all
access points feasible? What, if any, equally protective alternative exists
to permanent labeling in situations where an exhaust duct from a room may or
may not be carrying air containing aerosolized M. tuberculosis (e.g.,
the exhaust duct would only be carrying aerosolized M. tuberculosis
when an individual with infectious TB is being isolated in the room)? Dates 1.
OSHA has proposed that very small businesses with fewer than 20 employees be
given an additional 3 months to comply with the standard's engineering
control provisions (i.e., the start-up date for engineering controls for
small businesses would be 270 days from the Effective Date of the standard). Are
there other requirements of the proposed standard (e.g., respiratory
protection) for which very small businesses should be given additional time
to come into compliance? If so, for which provisions would they need
additional time and why? Are 20 employees an appropriate cut-off for this
purpose? Are there other employers that may need extended time to achieve
compliance? Definitions 1.
A number of provisions in the standard are triggered by the identification of
an individual as having "suspected infectious tuberculosis." Under
the definition of "suspected infectious tuberculosis", OSHA has
proposed criteria that the Agency believes are the minimum indicators that,
when satisfied by an individual, require an employer to consider that the
individual may have infectious tuberculosis. Are there other criteria that
should be included in this definition? 2.
Coverage of an employee under the standard is based upon the definition of
"occupational exposure." Similar to OSHA's Bloodborne Pathogens
standard, occupational exposure is dependent upon reasonable anticipation of
contact with an individual with suspected or confirmed infectious
tuberculosis or with air that may contain aerosolized M. tuberculosis.
Are there additions that could be made to this definition that would help
employers determine which of their employees are occupationally exposed? 3.
OSHA has proposed requirements for research laboratories that differ from
those of clinical laboratories. The standard includes definitions of
"research laboratory" and "clinical laboratory" to assist
the employer in differentiating between these two types of laboratory. Do the
definitions clearly differentiate between these two types of laboratories? Should
such a distinction be made? Are there any modifications that should be made
to these definitions? B. Information Collection Requirements This
proposed Tuberculosis standard contains collections of information that are
subject to review by the Office of Management and Budget (OMB) under the
Paperwork Reduction Act of 1995 (PRA'95), 44 U.S.C. 3501 et seq. and
the regulation at 5 CFR § 1320. PRA'95 defines collection of information to
mean, "the obtaining, causing to be obtained, soliciting, or requiring
the disclosure to third parties or the public of facts or opinions by or for
an agency regardless of form or format." [44 U.S.C. § 3502(3)(A)]. The
title, description of the need for and proposed use of the information,
summary of the collections of information, description of the respondents,
and frequency of response of the information collection are described below
with an estimate of the annual cost and reporting burden, as required by 5
CFR § 1320.5(a)(1)(iv) and § 1320.8(d)(2). Included in the estimate is the
time for reviewing instructions, gathering and maintaining the data needed,
and completing and reviewing the collection of information. OSHA
invites comments on whether the proposed collection of information: (1)
Ensures that the collection of information is necessary for the proper
performance of the functions of the agency, including whether the information
will have practical utility; (2)
Estimates the projected burden accurately, including whether the methodology
and assumptions used are valid; (3)
Enhances the quality, utility, and clarity of the information to be
collected; and (4)
Minimizes the burden of the collection of information on those who are to
respond, including through the use of appropriate automated, electronic,
mechanical, or other technological collection techniques or other forms of
information technology, e.g., permitting electronic submissions of
responses. Title: Tuberculosis
29 CFR 1910.1035. Description:
The proposed Tuberculosis (TB) Standard is an occupational safety and health
standard that will prevent or minimize occupational exposure to TB. The
standard's information collection requirements are essential components that
will protect employees from occupational exposure. The information will be
used by employers and employees to implement the protection required by the
standard. OSHA compliance officers will use some of the information in their
enforcement of the standard. Respondents:
The respondents are employers whose employees may have occupational exposure
in the following settings: hospitals; long-term care facilities for the
elderly; correctional facilities and other facilities that house inmates or
detainees; hospices; shelters for the homeless; facilities that offer
treatment for drug abuse; facilities where high hazard procedures are
performed; and laboratories that handle specimens that may contain M.
tuberculosis or process or maintain the resulting cultures, or perform
related activity that may result in the aerosolization of M. tuberculosis. Also,
occupational exposure occurring during the provision of social work, social
welfare services, teaching, law enforcement or legal services would be
covered if the services are provided in the work settings previously
mentioned, or in residences, to individuals who are in AFB isolation or are
segregated or otherwise confined due to having suspected or confirmed
infectious TB. Respondents also include employers whose employees are
occupationally exposed during the provision of emergency medical services,
home health care and home-based hospice care. Approximately 101,875 employers
will be responding to the standard. Total Estimated Cost: First year $62,972,210; Recurring years $53,691,915.
The
Agency has submitted a copy of the information collection request to OMB for
its review and approval. Interested parties are requested to send comments
regarding this information collection to the Office of Information and
Regulatory Affairs, Attn. OSHA Desk Officer, OMB New Executive Office
Building, 725 17th Street NW, Room 10235, Washington DC 20503. Comments
submitted in response to this notice will be summarized and/or included in
the request for Office of Management and Budget approval of the final
information collection request: they will also become a matter of public
record. Copies
of the referenced information collection request are available for inspection
and copying in the OSHA Docket Office and will be mailed immediately to any
person who request copies by telephoning Todd Owen at (202) 219-7075. For
electronic copies of the Tuberculosis information collection request, contact
the Labor News Bulletin Board (202) 219-4784, or OSHA web page on the
Internet at http://www.osha.gov/. Copies of the information collection
requests are also available at the OMB docket office. C. Federalism This
standard has been reviewed in accordance with Executive Order 12612, 52 FR
41685 (October 30, 1987), regarding Federalism. This Order requires that
agencies, to the extent possible, refrain from limiting State policy options,
consult with States prior to taking any actions that would restrict State
policy options, and take such actions only when there is clear constitutional
authority and the presence of a problem of national scope. The Order provides
for preemption of State law only if there is a clear Congressional intent for
the Agency to do so. Any such preemption is to be limited to the extent
possible. Throughout
the development of this proposed standard, OSHA has sought and received
assistance from state representatives. Representatives of state departments
of health and labor and industries have helped direct OSHA to pertinent
information and studies on TB and have submitted drafts of state standards
relevant to TB. In addition, representatives of state occupational safety and
health departments participated in the review of the draft standard by OSHA
field offices and in OSHA's TB Stakeholder meetings, where the requirements
of the proposed standard were presented and information was collected from
employers, employees, and their representatives on what was being done to
prevent occupational exposure to TB in the various worksites and how an OSHA
standard for TB could further reduce the exposures. Section
18 of the Occupational Safety and Health Act (OSH Act), expresses Congress'
clear intent to preempt State laws with respect to which Federal OSHA has
promulgated occupational safety or health standards. Under the OSH Act a
State can avoid preemption only if it submits, and obtains Federal approval
of, a plan for the development of such standards and their enforcement. Occupational
safety and health standards developed by such State-Plan states must, among
other things, be at least as effective in providing safe and healthful
employment and places of employment as the Federal standards. The
proposed tuberculosis standard is drafted so that employees in every State
will be protected by general, performance-oriented standards. To the extent
that there are State or regional peculiarities, States with occupational
safety and health plans approved under Section 18 of the OSH Act would be
able to develop their own State standards to deal with any special problems. Moreover,
the performance nature of this standard, of and by itself, allows for
flexibility by States and employers to provide as much safety as possible
using varying methods consonant with conditions in each State. There
is a clear national problem related to occupational safety and health for
employees exposed to M. tuberculosis. Approximately 6.5 % of the U.S.
adult population is infected (i.e., carrying the tuberculosis bacillus, not
manifesting active disease), and although the prevalence of TB infection and
disease varies throughout the country, TB disease has been reported in every
state. Political and geographic boundaries do not contain infection and
disease spread. The U.S. population is mobile, moving freely from place to
place for business and pleasure. Immigrants, a group whose members are known
to have a high prevalence of TB, settle throughout the country. While there
are counties that do not report cases in a given year, the counties change
from year to year along with the number of cases reported. In addition,
reports do not always reflect all the locations where exposure incidents can
occur; infectious TB cases are often transferred from their site of diagnosis
to a distant location for treatment and reported as a TB case only in the county
where treatment is administered. Finally, underreporting may occur because
some individuals with infectious TB, in particular the homeless and clients
of drug abuse facilities, do not avail themselves of further diagnosis and
treatment. TB infection and disease is truly national in scope. Those
States which have elected to participate under Section 18 of the OSH Act
would not be preempted by this regulation and would be able to deal with
special, local conditions within the framework provided by this performance-oriented
standard while ensuring that their standards are at least as effective as the
Federal standard. D. State Plans The
23 States and 2 territories with their own OSHA-approved occupational safety
and health plans must adopt a comparable standard within 6 months after the
publication of a final standard for occupational exposure to tuberculosis or
amend their existing standard if it is not "at least as effective"
as the final Federal standard. OSHA anticipates that this standard will have
a substantial impact on state and local employees. The states and territories
with occupational safety and health state plans are: Alaska, Arizona,
California, Connecticut, Hawaii, Indiana, Iowa, Kentucky, Maryland, Michigan,
Minnesota, Nevada, New Mexico, New York, North Carolina, Oregon, Puerto Rico,
South Carolina, Tennessee, Utah, Vermont, Virginia, the Virgin Islands,
Washington, and Wyoming. (In Connecticut and New York, the plan covers only
State and local government employees). Until such time as a State standard is
promulgated, Federal OSHA will provide interim enforcement assistance, as
appropriate. II. Pertinent Legal Authority The
purpose of the Occupational Safety and Health Act, 29 U.S.C. 651 et seq.
("the Act") is "to assure so far as possible every working man
and woman in the nation safe and healthful working conditions and to preserve
our human resources." 29 U.S.C. § 651(b). To achieve this goal Congress
authorized the Secretary of Labor to promulgate and enforce occupational
safety and health standards. 29 U.S.C. Secs. 655(a) (authorizing summary
adoption of existing consensus and federal standards within two years of
Act's enactment), 655(b) (authorizing promulgation of standards pursuant to
notice and comment), 654(b) (requiring employers to comply with OSHA
standards). A
safety or health standard is a standard "which requires conditions, or
the adoption or use of one or more practices, means, methods, operations, or
processes, reasonably necessary or appropriate to provide safe or healthful employment
or places of employment." 29 U.S.C. § 652(8). A
standard is reasonably necessary or appropriate within the meaning of Section
652(8) if it substantially reduces or eliminates significant risk, and is
economically feasible, technologically feasible, cost effective, consistent
with prior Agency action or supported by a reasoned justification for
departing from prior Agency actions, supported by substantial evidence, and
is better able to effectuate the Act's purposes than any national consensus
standard it supersedes. See 58 Fed. Reg. 16612 -- 16616 (March 30, 1993). OSHA
has generally considered, at a minimum, a fatality risk of 1/ 1000 over a
45-year working lifetime to be a significant health risk. See the Benzene
standard, Industrial Union Dep't v. American Petroleum Institute,
448 U.S. 607, 646 (1980); the Asbestos standard, International Union, UAW
v. Pendergrass, 878 F.2d 389, 393 (D.C. Cir. 1989). A
standard is technologically feasible if the protective measures it requires
already exist, can be brought into existence with available technology, or
can be created with technology that can reasonably be expected to be
developed. American Textile Mfrs. Institute v. OSHA, 452 U.S.
490, 513 (1981) ("ATMI"), American Iron and Steel
Institute v. OSHA, 939 F.2d 975, 980 (D.C. Cir. 1991)("AISI"). A
standard is economically feasible if industry can absorb or pass on the costs
of compliance without threatening its long-term profitability or competitive
structure. See ATMI, 452 U.S. at 530 n. 55; AISI, 939 F.2d at
980. A
standard is cost effective if the protective measures it requires are the
least costly of the available alternatives that achieve the same level of
protection. ATMI, 453 U.S. at 514 n. 32; International Union, UAW v.
OSHA, 37 F.3d 665, 668 (D.C. Cir. 1994) ("LOTO III"). All
standards must be highly protective. See 58 FR 16614 -- 16615; LOTO III,
37 F.3d at 669. However, health standards must also meet the
"feasibility mandate" of Section 6(b)(7) of the Act, 29 U.S.C. §
655(b)(5). Section 6(b)(5) requires OSHA to select "the most protective
standard consistent with feasibility" that is needed to reduce
significant risk when regulating health hazards. ATMI, 452 U.S. at
509. Section
6(b)(5) also directs OSHA to base health standards on "the best available
evidence," including research, demonstrations, and experiments. 29
U.S.C. § 655(b)(5). OSHA shall consider "in addition to the attainment
of the highest degree of health and safety protection * * * the latest
scientific data * * * feasibility and experience gained under this and other
health and safety laws." Id. Section
6(b)(7) authorizes OSHA to include among a standard's requirements labeling,
monitoring, medical testing and other information gathering and transmittal
provisions. 29 U.S.C. § 655(b)(7). Finally,
whenever practical, standards shall "be expressed in terms of objective
criteria and of the performance desired." Id. III. Events Leading to the Proposed Standard Tuberculosis
(TB) is a contagious disease caused by the bacterium Mycobacterium
tuberculosis (M. tuberculosis). Infection is usually acquired by the
inhalation of airborne particles carrying the bacterium. These airborne
particles, called droplet nuclei, can be generated when persons with
infectious pulmonary or laryngeal TB cough, sneeze, or speak. TB has long
been considered an occupational hazard in the health care setting. However,
it is inhalation exposure to aerosolized M. tuberculosis and not some
other factor unique to the health care setting that places workers at risk of
infection. Thus, any work setting where employees can reasonably be
anticipated to encounter individuals with infectious TB also contains the
occupational hazard of TB infection. On
December 21, 1992, the Labor Coalition to Fight TB in the Workplace (the Coalition)
requested the Agency to issue nationwide enforcement guidelines to protect
workers against exposure to TB in health care, criminal justice, and other
high risk settings and to issue a Joint Advisory Notice on TB in conjunction
with the Centers for Disease Control and Prevention (CDC) (Ex. 2). This
petition was signed by the presidents of the Service Employees International
Union (SEIU), the American Federation of State, County, and Municipal
Employees (AFSCME), and the American Federation of Teachers (AFT), and was
endorsed by 9 other unions. The petition included a list of provisions that
the petitioners felt should be included in the guidelines, ranging from a
written control plan and medical surveillance to anti-discrimination language
and medical removal protection. Eight
months later, on August 25, 1993, the Coalition petitioned OSHA to initiate
rulemaking for a permanent standard issued under § 655(b) of the Act to
protect workers from occupational transmission of TB (Ex. 1). Citing the
recent resurgence of TB and the emergence and increasing rate of new cases of
multidrug-resistant TB (MDR-TB), the petitioners stressed the need for a
substance-specific standard to address the hazards associated with
occupational exposures to TB. The petitioners contended that the
non-mandatory CDC TB Guidelines do not provide adequate protection because
they are not fully or rigorously implemented in most workplaces. They also
stated that in every outbreak of TB investigated by CDC, noncompliance with
the Guidelines was evident. In
addition to a permanent standard, the petitioners also requested that OSHA
immediately issue the nationwide enforcement guidelines that the Coalition
had previously requested, and that OSHA promulgate an Emergency Temporary
Standard (ETS) as an interim measure. The Coalition requested that the
standard be applicable to all work settings where employees can reasonably
anticipate contact with infectious TB. The petition included a discussion on
occupational risk that included both the traditional high-risk occupations
and other occupations such as sheet metal workers, postal workers, airline
employees, teachers, and office workers. Like
the request for nationwide enforcement guidelines, the petition contained
provisions that the petitioners requested be included in the standard. Examples
include a facility hazard assessment and written exposure control plan,
engineering and work practice controls, respiratory protection, medical
surveillance (e.g., tuberculin skin testing) and counseling, post-exposure
management, outbreak management, training, and recordkeeping. On
October 8, 1993, OSHA issued nationwide enforcement procedures for
occupational exposure to TB. The compliance document contained the
enforcement procedures that the Agency could and would use in certain work
settings for protecting workers with occupational exposure to TB. In the
compliance procedures, the Agency noted that although OSHA has no standard
designed specifically to reduce occupational exposure to TB, the Agency has existing
standards that apply to this hazard. For example, 29 CFR 1910.134 requires
employers to provide respiratory protection equipment and 29 CFR 1910.145(f)
requires accident prevention tags to warn of biological hazards. In addition,
section 5(a)(1), the General Duty Clause of the Act, requires that each
employer: *
* * furnish to each of his employees employment and a place of employment
which are free from recognized hazards that are causing or are likely to
cause death or serious physical harm to his employees. On
January 26, 1994, in response to their August 25 petition, Secretary of Labor
Robert B. Reich informed the petitioners that OSHA was initiating rulemaking
on a permanent standard to be issued under Section 6(b)(5) of the Act for
occupational exposure to TB (Ex. 1B). At the same time, the petitioner's
request for an ETS was denied. The Agency had determined that the available
data did not meet the criteria for an ETS as set forth in Section 6(c) of the
Act. However, OSHA committed to enforcing existing regulations and Section
5(a)(1) of the Act in certain work settings while preparing this standard. On
October 28, 1994 the CDC issued revised guidelines for preventing the
transmission of tuberculosis in health care facilities (Ex. 4B). In addition,
in June of 1995, the National Institute for Occupational Safety and Health
(NIOSH) published revised certification procedures for non-powered air
purifying particulate respirators (Ex. 7-261). As a result of changes in
these two documents, OSHA issued revised enforcement policies and procedures
relative to TB in February of 1996 (Ex. 7-260). In
October and November of 1995, OSHA held a series of meetings with stakeholder
groups representing labor unions, professional organizations, trade
associations, state and federal government, representatives of employers, as
well as frontline workers from the various sectors anticipated to be covered
by the proposed standard. During these meetings, participants provided input
relative to the concepts and approaches OSHA was considering for the proposed
tuberculosis standard. In
September of 1996, in accordance with the Small Business Regulatory
Enforcement Fairness Act of 1996 (SBREFA), a Small Business Advocacy Review
Panel was convened to consider the impact of OSHA's draft proposed
tuberculosis standard on affected small entities. The panel, comprised of
members from the Office of Advocacy of the Small Business Administration
(SBA), the Office of Management and Budget (OMB), and OSHA, prepared a report
based on the Panel's findings and recommendations with regard to comments on
the standard received from small business employers. This report was
submitted to the Assistant Secretary for OSHA for its consideration during
the development of the standard (Ex. 12). OSHA's proposed standard reflects
input generated during both the stakeholder meetings and the SBREFA review
process. Comparison of OSHA's Proposed Standard and CDC's Revised Guidelines In
preparing its proposed standard for TB, OSHA has relied heavily on the expertise
of CDC. The Agency has consulted with CDC and has incorporated the basic
elements of CDC's revised guidelines for preventing the transmission of M.
tuberculosis in health care facilities in this proposed standard. Both
CDC and OSHA rely on minimizing exposures and consequent transmission by
identifying suspected infectious TB individuals and isolating them. The OSHA
proposed standard includes the following CDC components: written exposure
control plans, procedures for early identification of individuals with
suspected or confirmed infectious TB, procedures for initiating isolation of
individuals with suspected or confirmed infectious TB or for referring those
individuals to facilities with appropriate isolation capabilities, procedures
for investigating employee skin test conversions, and education and training
for employees. In addition, OSHA has incorporated CDC recommendations for
engineering control measures such as the use of negative pressure for AFB
isolation rooms or areas, daily monitoring of negative pressure while AFB
isolation rooms are in use for TB, HEPA filtration of recirculated air from
AFB isolation rooms, and periodic maintenance and monitoring of engineering
controls. With regard to respiratory protection, OSHA has adopted CDC's standard
performance criteria for the selection of respiratory protection devices
appropriate for use against M. tuberculosis. And finally, where
appropriate, OSHA has attempted to assure that where certain practices are
required by OSHA's proposed standard, e.g., tuberculin skin testing
and medical management and follow-up of employees who acquire TB infections
or active disease, these practices are conducted according to the current
recommendations of the CDC. Therefore, OSHA's proposed standard for occupational
exposure to TB closely follows CDC's recommended elements for a TB infection
control program. However,
there are some minor differences between OSHA's proposed standard and CDC's
guidelines that gobeyond the obvious enforcement distinction between a
guideline and a standard. These differences are found primarily in the areas
of risk assessment, medical surveillance and respiratory protection. Even so,
OSHA believes that despite these differences the vast majority of the
provisions included in this proposed standard closely track the
recommendations of the CDC. The following discussion identifies where these
differences occur and describes the extent of these differences and the
degree to which they impact on employers' responsibilities under the proposed
standard. Risk Assessment As
a part of its guidelines, CDC recommends that a risk assessment be conducted
in all facilities to assess the risk of transmission of M. tuberculosis
in each facility. This risk assessment is to be conducted using information
such as the profile of TB in the community, the number of suspected and
confirmed cases of TB among patients and health care workers>>, results of health care worker
tuberculin skin testing (i.e., conversion rates), and observation of TB
infection control practices. Using the results of this risk assessment,
appropriate infection control interventions can then be selected based on the
actual risk in the facility. CDC includes a protocol for conducting this risk
assessment in which there are 5 categories of risk: "minimal",
"very-low", "low", "intermediate", and
"high". Each category from "minimal" to "high"
has an increasing number of infection control interventions that are
recommended for each particular level of risk. OSHA,
however, has chosen a simpler approach and is not requiring employers to
conduct such a risk assessment. Consistent with other standards, OSHA has
determined that employees in the work settings and employees providing
services set forth in the scope section are at risk of occupational exposure
to TB. Their employers are required to conduct an exposure assessment to
determine which employees have occupational exposure, i.e., reasonably
anticipated contact with an individual with suspected or confirmed infectious
TB or air that may contain aerosolized M. tuberculosis. The standard
then specifies the provisions applicable for the employees whom the employer
has identified as having occupational exposure. In addition, consistent with
its approach in other standards, OSHA does not require that individual risk
assessments be conducted by each work setting covered under the standard, as
they may be too difficult and burdensome for employers to prepare. Also, many
work settings will have too few occupationally exposed employees to do an
accurate risk assessment. Finally, conducting the risk assessments in order
to determine applicable duties may require a level of expertise some
facilities lack, making enforcement burdensome for the Agency. OSHA
realizes, however, that in many work settings, very few individuals with
suspected or confirmed infectious TB may be seen and that in many of those
work settings, individuals with suspected or confirmed infectious TB will be
transferred to other facilities that are better equipped to provide services
and care using appropriate TB isolation precautions. Because there is likely
to be less risk of transmission of M. tuberculosis in those
situations, OSHA believes that it is possible to make the standard less
burdensome for the employers with these types of work settings while still
maintaining worker protection. For
example, an employer who can demonstrate that his or her facility or work
setting: (1) Does not admit or provide medical services to individuals stwith
suspected or confirmed infectious TB, (2) has not had any individuals with
confirmed infectious TB within the work setting within the last 12 months,
and (3) is located in a county that, in the past 2 years, has had 0 cases of
confirmed infectious TB reported in one year and fewer than 6 cases of
confirmed infectious TB reported in the other year, does not have to comply
with all provisions of the standard. Such employers would only be responsible
for compliance with certain provisions, e.g., a written exposure
control plan, a baseline skin test and medical history, medical management
and follow-up after exposure incidents, medical removal protection where
necessary, employee training, and recordkeeping. These provisions are very
similar to the recommendations of the CDC for facilities classified as having
"minimal risk," i.e., no TB in the community or in the facility. The
only major difference is that CDC does not recommend baseline skin testing. However,
CDC does state that baseline skin testing would be advisable so that if an
unexpected exposure does occur, conversion could be distinguished from
positive skin test results caused by previous exposures. Medical Surveillance In
the area of medical surveillance, the main differences between OSHA and CDC
are related to tuberculin skin testing. OSHA requires baseline skin testing
for all employees whom the employer identifies as having occupational
exposure. CDC recommends baseline skin testing for all employees with
potential exposure except those who work in facilities that fall into CDC's
"minimal risk" category. However, CDC notes that even for employees
in "minimal risk" facilities, it may be advisable to perform
baseline skin testing so that if unexpected exposures do occur, conversions
can be distinguished from positive skin test results caused by previous
exposures. Thus, there is little difference between OSHA requirements and CDC
recommendations with regard to baseline skin testing. Relative
to periodic skin testing, OSHA requires periodic re-testing for all employees
identified as having occupational exposure who have negative skin tests
except for the employees of those employers who have no TB in the community
and who have not encountered any individuals with confirmed infectious TB in
their work settings within the past year. CDC recommends re-testing for
employees in the "low", "intermediate", and
"high" risk categories. According to the CDC guidelines, periodic
re-testing is not necessary for employees in the "minimal" risk
category or the "very-low" risk categories. CDC's periodic skin
test recommendations for the "minimal" risk category are similar to
OSHA's limited program for employers who do not admit or provide medical
services to individuals with suspected or confirmed infectious TB, have not
encountered any confirmed infectious TB in their work setting, and are
located in a county that, in the past 2 years, has reported 0 cases of
confirmed infectious TB in one year and fewer than 6 cases in the other year.
OSHA is different from the CDC in that employees in a "very-low risk
category" are required to be periodically retested. However, CDC notes
that even in the "very-low" risk category, employees who are
involved in the initial assessment of individuals in emergency departments
and admitting areas may have potential exposure and thus may need periodic
re-testing. Another
difference between CDC and OSHA is the frequency of the re-testing. This is
primarily due to the fact that OSHA's required frequencies are based on the
type of work that employees do that result in exposures whereas CDC's
recommendations are based more on evidence of conversions. For example, OSHA
requires re-testing every six months for all employees who (1) enter AFB
isolation rooms or areas, (2) perform high-hazard procedures, (3) transport
individuals with suspected or confirmed infectious TB in an enclosed vehicle,
or (4) work in intake areas where early identification procedures are
performed (e.g., emergency departments, admitting areas) in facilities
where 6 or more individuals with confirmed infectious TB have been
encountered in the past 12 months. For all other employees with occupational
exposure, re-testing is required every 12 months. In comparison, CDC
recommends re-testing every year for employees in "low" risk
categories, every 6-12 months for employees in "intermediate" risk
categories, and every 3 months for employees in "high" risk
categories. Under CDC recommendations, employees in "low" risk
categories who enter AFB isolation rooms or areas or employees who transport
individuals with suspected or confirmed infectious TB in an enclosed vehicle
would be re-tested every 12 months. However, under OSHA requirements, those
same employees would be required to be re-tested every six months. Thus, OSHA
is more protective than CDC in this case. OSHA
also would require that employees who perform high-hazard procedures or who
work in intake areas where early identification procedures are performed in
facilities that encounter 6 or more individuals with confirmed infectious TB
be re-tested every six months. Under CDC's Guidelines employees in areas in
which cough-inducing procedures are performed on individuals who may have
active TB are recommended to follow an intermediate risk protocol. Similarly,
CDC recommends that an intermediate risk protocol be followed in areas where
more than six individuals who may have active TB receive initial assessment
and diagnostic evaluation (e.g., ambulatory care, emergency
departments, admitting areas). CDC recommends re-testing every 6-12 months
for employees in intermediate risk categories. OSHA would require re-testing
every 6 months for the two situations above, which is very similar to CDC's
recommendation of re-testing every 6-12 months. CDC
is more protective in its recommendations for employees in the "high"
risk category. These employees are recommended to be re-tested every 3
months. OSHA does not have a requirement for re-testing employees every 3
months. However, after an exposure incident, OSHA requires that a skin test
be administered as soon as feasible and again 3 months after the exposure
incident, if the first skin test is negative. Since it is possible that an
exposure incident(s) could be the type of event that would cause an
employee(s) to be included in the "high" risk category as defined
by CDC, OSHA requirements, to some extent, track the CDC recommendations for
a higher frequency of periodic skin testing. With
regard to two-step testing, both OSHA and CDC require or recommend two-step
testing at the time baseline skin testing is administered. Also, both OSHA
and CDC add that two-step testing is not necessary if the employee has had a
documented negative skin test within the last 12 months. CDC is different
from OSHA in that its Guidelines imply that two-step testing can be
discontinued if there is evidence of a low frequency of boosting in the
facility. OSHA's proposed standard does not allow such an exemption, i.e.,
for each employee who must have a baseline skin test at the time of the
initial medical examination, the skin test must include a two-step test
unless the employee has a documented negative test within the last 12 months,
regardless of the frequency of boosting in the facility. The value of
two-step skin testing is that it enables one to distinguish true conversions
from boosted reactions. OSHA believes that this is important to know for each
employee because if the employee is incorrectly identified as having
converted, he or she may needlessly be subjected to preventive therapy that
may have toxic side effects of its own. Since it is important to know the
true skin test status for each employee, OSHA has preliminarily concluded
that it is inappropriate to allow the overall frequency of boosting among
employees in a facility to dictate whether any one employee receives two-step
testing at the time of his or her baseline testing. Respiratory Protection OSHA
requirements and CDC recommendations for respiratory protection are very
similar. A respirator is a personal protective equipment device worn over the
nose and mouth of the employee that filters certain airborne contaminants
from the inhaled air. OSHA has adopted CDC's performance criteria for
respirators appropriate for use for TB. Also, both OSHA and CDC have similar
requirements or recommendations that respirators be worn when entering an
isolation room, when performing cough-inducing procedures or
aerosol-generating procedures on an individual with suspected or confirmed
infectious TB, when repairing or maintaining air systems that may contain
aerosolized M. tuberculosis, when transporting an individual with
suspected or confirmed infectious TB in an enclosed vehicle and when working
in a residence where an individual with suspected or confirmed infectious TB
is known to be present. However, OSHA also requires that respirators be worn
when employees are transporting individuals with suspected or confirmed
infectious TB within the facility if those individuals are not masked (e.g.,
a surgical mask or a valveless respirator). CDC does not have a similar
recommendation for respiratory protection while transporting individuals
within the facility, but CDC does recommend, and assumes to some extent, that
individuals with suspected or confirmed infectious TB are masked whenever
they are outside an isolation room. In addition, OSHA requires that
respirators be worn when employees work in an area where an unmasked
individual with suspected or confirmed infectious TB has been segregated or
otherwise confined. For example, this provision would cover employees such as
those who work in admitting areas and must attend to unmasked individuals
with suspected or confirmed infectious TB while those individuals are
awaiting transfer. These types of employees are likely to be found in
facilities that would meet CDC's definition of "minimal" risk. CDC
states that respiratory protection is not necessary for employees in the
"minimal" risk category. However, again, CDC recommends that if an
individual with suspected or confirmed infectious TB is identified in a
"minimal" risk facility, the individual should be masked while he
or she is awaiting transfer to another facility, thus obviating the need for
respiratory protection. OSHA, on the other hand, cannot require employers to
mask clients or patients in a facility, and the Agency must therefore include
provisions for respirator use to protect potentially exposed employees. However,
consistent with CDC, OSHA proposes not to require respirators where the
employer elects, as a part of his or her own administrative policies, to mask
individuals with suspected or confirmed infectious TB. Thus, when individuals
with suspected or confirmed infectious TB are masked while they are awaiting
transfer to another facility or while they are being transported within the
facility, employees would not be required by the standard to wear a
respirator. In
some instances, the CDC may be more protective than OSHA with regard to
respiratory protection. The CDC states that the facility's risk assessment
may identify selected settings where the estimated risk of transmission of M.
tuberculosis may be such that a level of respiratory protection exceeding
the standard performance criteria is appropriate (e.g., more
protective negative pressure respirators, powered air purifying respirators).
The examples given of such selected settings are a bronchoscopy performed on
an individual suspected of having TB and an autopsy performed on a deceased
person suspected of having had active TB at the time of death. OSHA does not
have a similar requirement for more protective respiratory protection. Respirators
meeting the minimal performance criteria laid out by the standard would be
required by OSHA for employees performing all high-hazard procedures,
including bronchoscopies and aerosol-generating autopsy procedures. IV. Health Effects For
centuries Tuberculosis (TB) has been responsible for the death of millions of
people throughout the world. It was not until 1882, however, that Robert Koch
identified a species of bacteria, Mycobacterium tuberculosis (M.
tuberculosis), as the cause of TB. TB
is a communicable disease that usually affects the lungs. The airborne route
is the predominant mode of transmission, a situation created when individuals
with infectious TB discharge the bacilli from the lungs when coughing,
sneezing, speaking or singing. Some individuals who breathe contaminated air
become infected with TB. Most often, the immune system responds to fight the
infection. Within a few weeks, the infected lesions become inactive and there
is no residual change except for possible lymph node calcifications. These
individuals will have a positive skin test result. They will harbor the
infection for life. At some time in the future, the infection can progress
and can become an active disease, with pulmonary infiltration, cavitation, and
fibrosis, possibly causing permanent lung damage and even death. With some
exceptions, however, TB is treatable with antimicrobial drugs. If the active
TB is treated early, there will be minimal residual lung damage. For this
reason, individuals who have a TB exposure incident and develop a TB
infection are treated to prevent progression to active TB disease. With
the introduction of antimicrobial drug treatment in the 1940s and the
creation of programs in the United States such as the U.S. Public Health Service's
Tuberculosis Program, there began a decline in the incidence of active TB
cases in the U.S. From 1953, when active cases began to be reported in the
U.S., until 1984, the number of annual reported cases declined 74 %, from
84,304 (53 per 100,000) to 22,255 (9.4 per 100,000) (Ex. 7-50). However, this
steady decline in TB cases did not continue. Instead, from 1985 through 1992,
the number of reported TB cases increased 20.1 % from 22,201 to 26,673 (10.5
cases per 100,000) (Ex. 6-13). This
resurgence in TB brought to attention a number of problems in the existing TB
control programs. The direction of resources to areas with the highest
increase in active cases has caused this increase to decline. The number of
cases reported for 1995 indicates that the rate of active TB has returned to
its 1985 levels. In 1995, a total of 22,813 cases of TB (8.7 per 100,000) was
reported to CDC (Ex. 6-34). While this represents a decline in active TB, the
1995 rate is still two and one half times greater than the target case rate
of 3.5 per 100,000 for the year 2000 and approximately 87 times the goal of
less than one case per million population by the year 2010 proposed by the
Advisory Committee on the Elimination of Tuberculosis (Ex. 6-19). TB
continues to be a national problem. Each year, cases of active disease are
reported in every state in the Nation and in a substantial majority of
counties nationwide. CDC estimated in 1990 that approximately 10 million
people were infected with the tuberculosis bacterium and that approximately
90 % of the new cases of active disease that arise in the United States come
from this already infected group (Ex. 7-52). Given the recent resurgence of
TB, it is likely that a new population of individuals has been infected as
well. Of great concern are strains of M. tuberculosis that have
emerged that are resistant to several of the first-line anti-TB drugs
normally used to treat TB infection and disease (e.g., isoniazid and
rifampin). This drug-resistant form of the disease, referred to as
multidrug-resistant TB or MDR-TB, is more often a fatal form of TB due to the
difficulty in finding antimicrobial drugs to stop the bacteria's growth and
progressive tissue destruction. In addition, individuals with MDR-TB often
remain infectious for longer periods of time due to delays in diagnosing
resistance patterns and initiating appropriate treatment. This, in turn,
increases the risk that infectious individuals will transmit the organism to
other persons coming in contact with them. Most
of the decreases in reported cases of TB since 1992 have occurred in areas
such as New York City, where resources have been invested to improve or
initiate TB control provisions, such as those outlined in OSHA's proposed
standard. However, the 1995 statistics show that over the course of four
years there is substantial variability in the increases and decreases of
cases reported by each state for any given year (Ex. 6-34). In 1995, 15
states reported an increase in the number of TB cases compared with 1994. In
addition, a recent study has shown that MDR-TB has spread to patients in
Florida and Nevada, and to <<health care workers>> in Atlanta, Georgia and Miami,
Florida. Moreover, one individual with MDR-TB infected or caused disease in
at least 12 people in a nursing home in Denver, Colorado (Ex. 7-259). This
study shows very clearly the ability of TB to be spread to different areas of
the country. This is to be expected given the mobile nature of today's
society and the frequency with which people travel. Immigration also
contributes to the incidence of the disease. For example, while the number of
active TB cases has decreased among U.S. born persons, the number of foreign
born persons reported with TB has increased 63 % since 1986, with a 5.4 %
increase in 1995 (i.e., from 7,627 cases in 1994 to 8,042 cases in 1995). Thirty
to fifty percent of these cases were diagnosed 1 to 5 years after the
individual enters the U.S. (Ex. 6-34). Thus, tuberculosis continues to be a
public health problem throughout the United States. The
following discussion will briefly describe the basic concepts and terminology
associated with TB as well as common factors that facilitate its transmission
from one individual to another. This discussion will also include a review of
studies relating to the occupational transmission of TB. Background TB
is a contagious disease caused by the bacterium M. tuberculosis. Infection
is generally acquired by the inhalation of airborne particles carrying the
bacterium. These airborne particles, called droplet nuclei, can be generated
when persons with pulmonary or laryngeal tuberculosis in the infectious state
of the disease cough, sneeze, speak or sing. In
some individuals exposed to droplet nuclei, tuberculosis bacilli enter the
lung and establish an infection (Ex. 7-52). Once in the alveoli, the
tuberculosis bacilli are taken up by alveolar macrophages and spread
throughout the body by the lymphatic system, until the immune response limits
further growth (usually a period of two to ten weeks). In most cases the
tuberculosis bacilli are contained by the immune response. Macrophage cells
engulf the bacteria, which limits the spread of the bacilli. Initial lesions
from infection heal; however, small calcifications called tubercles are
formed and may remain a potential site of later reactivation. Individuals
in this state are infected with TB. They will show a positive skin test and
they are at risk of developing active TB, a risk they carry throughout their
lifetime. In many cases, as described below, preventive therapy is initiated
with anti-TB drugs to prevent the progression to active TB disease. These
drugs are toxic and may cause adverse effects such as hepatitis. Severe
preventive therapy-associated hepatitis cases have necessitated liver
transplants and in some cases have resulted in death (Ex. 6-10). When
the bacilli are not contained by the immune system, they continue to grow and
invade the tissue, leading to the progressive destruction of the organ involved,
which in most cases is the lung, i.e., pulmonary tuberculosis. The
inflammatory response caused by the disease produces weakness, fever, chest
pain, cough, and, when blood vessels are eroded, bloody sputum. Also, many
individuals have drenching night sweats over the upper half of the body
several times a week (Ex. 5-80). The extent of disease varies from minimal
symptoms of disease to massive involvement with extensive cavitation and
debilitating constitutional and respiratory symptoms. Since tuberculosis
bacilli are spread throughout the body after the initial infection, other
organs may also be infected and disease may occur at sites outside the lung,
i.e., extrapulmonary tuberculosis. There
are two general stages of TB, tuberculosis infection and active tuberculosis
disease. Individuals with tuberculosis infection and no active disease are
not infectious. These tuberculosis infections are asymptomatic or subclinical
and are only detected by a positive response to a tuberculin skin test. However,
there are some individuals whose immune system is impaired and cannot mount a
sufficient response to skin test antigens, i.e., they are anergic. Such
individuals may be infected, although they do not show a positive response to
the skin test. Individuals with tuberculosis infection and no disease would
have negative bacteriologic studies and no clinical or radiographic evidence
of tuberculosis disease. However, these individuals are infected for life and
are at risk of developing active TB in the future. Anti-tuberculosis
drugs may be used for individuals with TB infection but who do not have
active disease. In these cases, the antimicrobials are used as preventive
therapy to prevent the onset of active disease. Because of the toxicity
associated with the antimicrobials, preventive therapy may not be appropriate
for all infected individuals. Various factors are considered to determine
whether an infected individual is an appropriate candidate for preventive
therapy (e.g., age, immune status, how recently the infection
occurred, and other high-risk factors associated with TB) (Ex. 7-52, pg. 17).
Isoniazid is currently the only drug that has been well tested in humans for
its efficacy as preventive therapy (Ex. 7-50, pg. 61). However, serious side
effects may result from isoniazid. A study in New York for the years 1991 to
1993 examined cases of hepatitis induced by isoniazid preventive therapy. In
this study, 10 patients undergoing preventive therapy for TB were identified
at a transplant center. Eight of these patients had developed hepatitis from
isoniazid. Five received a liver transplant; the other three died while
awaiting a liver donor. In addition, one of the transplant patients died
after transplantation. Thus, preventive therapy may carry considerable risks
for infected individuals. In
those cases where isoniazid cannot be tolerated by the patient or where it is
suspected that infection resulted from exposure to isoniazid-resistant
strains of M. tuberculosis, rifampin may be recommended for preventive
therapy. Considerations for such alternative drug therapies are made on a
case-by-case basis by the health care provider based on the medical and case
history of the infected patient. Rifampin has adverse side effects as well. However,
preventive therapy using rifampin has not been followed as well as that
involving isoniazid and therefore, its side effects are less well
characterized. Individuals
with active TB have clinical and/or radiographic evidence of disease. The
initial laboratory method for diagnosing TB is the Acid Fast Bacilli (AFB)
smear. This is a quick and easy technique in which body fluids, typically
sputum samples, from individuals with suspected TB are examined for
mycobacteria. However, this type of test only permits a presumptive diagnosis
of TB since the test cannot distinguish between tuberculosis mycobacteria and
other non-tuberculosis mycobacteria. Chest X-rays may also be used to
diagnose active TB; however, some individuals with TB may have X-ray findings
that are atypical of those usually associated with TB (e.g., HIV
infected individuals). The diagnosis of clinically active TB is most
definitively established by the isolation of M. tuberculosis in
culture. However, it may take three to six weeks or longer from obtaining a
culture to getting a result. Individuals
with active TB disease may be infectious, especially if they are untreated or
inadequately treated and if the disease is in the lungs. The clinical
symptoms of pulmonary TB include loss of appetite, weight loss, fatigue,
fever, night sweats, malaise, cough with productive sputum and/or blood, and
chest pain. The extent of the disease varies from very minimal symptoms to
extensive debilitating constitutional and respiratory symptoms. If untreated,
the pulmonary TB follows a chronic and progressive course in which the tissue
is progressively destroyed. It has been estimated that approximately 40 to 60
% of untreated cases result in death (Exs. 5-80, 7-50, and 7-66). However,
even among cured cases of TB, long-term damage can result, including impaired
breathing due to lung damage (Ex. 7-50, pg. 31). Approximately
90 % of immunocompetent adults who are infected do not develop active TB
disease. However, for 10 % of infected immunocompetent adults, either
directly after infection or after a latency period of months, years or even
decades, the initial infection progresses to clinical illness, that is,
active TB (Ex. 4B). The risk of developing active TB is increased for
individuals whose immune system is impaired (i.e., immunocompromised). Such
individuals include persons undergoing treatment with corticosteroid or
immunosuppressive drugs (e.g., persons with organ transplants or
persons undergoing chemotherapy for cancer), persons suffering from
malnutrition or chronic conditions such as asthma and emphysema, and persons
infected with the human immunodeficiency virus (HIV). The
main first-line drugs currently used to treat active TB are isoniazid,
rifampin, pyrazinamide, ethambutol and streptomycin. Combinations of these
antimicrobials are used to attack the tuberculosis bacilli in the body. Recommended
treatment regimens include two or more drugs to which the bacilli are
susceptible, because the use of a single drug can lead to the development of
bacilli resistant to that drug (Ex. 5-85). Treatment with these first-line
drugs involves a two-phase process: an initial bactericidal phase for the
quick elimination of the bulk of bacilli from most body sites and a
longer-term sterilizing phase for eliminating the remaining bacilli. Different
regimes of drug treatment (i.e., the types of drugs and frequency of
administration) are recommended depending on the medical history of the
patient involved and the results of drug susceptibility testing. The U.S.
Public Health Service has recommended options for the initial therapy and
dosage schedules for the treatment of drug-susceptible TB (Ex. 4B). While
these antimicrobials are effective in the treatment of active TB, some of
these drugs also have toxic potential. Adverse side effects of these drugs
include hepatitis, peripheral neuropathy, optic neuritis, ototoxicity and
renal toxicity (Ex. 7-93). Thus, patients undergoing TB therapy must also be
monitored for drug toxicity that may occur from anti-tuberculosis drugs. Individuals
with active disease who are infectious may need to be hospitalized in order
to provide isolation so that they will not infect other individuals. After
the initiation of treatment for active TB, improvement of the disease can be
measured through clinical observations such as loss of fever, reduction in
coughing, increased appetite and weight gain. A reduction in the number of
bacilli in sputum smears also indicates improvement. Three consecutive
negative sputum smears generally indicate that the individual is no longer
infectious. However, decisions about infectiousness are usually determined on
a case-by-case basis after taking a number of factors into consideration,
such as the presence of cough, the positivity of sputum smears, and the
status or response to chemotherapy. Although no longer infectious to other
individuals, the individual undergoing treatment still has tuberculosis
disease and must continue treatment. Discontinuing or erratically adhering to
the treatment regime can allow some of the bacilli to survive such that the individual
will be at risk of becoming ill and infectious again (Ex. 7-52, p. 25). Not
all strains of the tuberculosis bacilli are susceptible to all of the
antimicrobials used to treat TB. In some instances, drug-resistant forms of M.
tuberculosis may emerge. Drug resistance may emerge by 1 of 3 mechanisms
(Exs. 5-85; 7-50, pp. 44-47). Drug-resistant TB may occur naturally from
random mutation processes, i.e., primary resistance. In addition,
drug-resistant TB may result due to inadequate or erratic treatment, i.e.,
acquired resistance. In these cases, erratic or inadequate treatment allows
the tuberculosis bacilli to become resistant to one or several of the drugs
being used. Finally, drug-resistant TB may result due to the active
transmission of drug-resistant TB from an individual already infected with
drug-resistant strains of the tuberculosis bacteria, i.e., transmitted
resistance. In recent years, drug-resistant forms of TB have emerged that are
resistant to two or more of the first-line drugs used to treat TB, such as
isoniazid and rifampin, two of the most effective anti-TB drugs. These
drug-resistant forms of the disease are referred to as multidrug-resistant TB
or MDR-TB. MDR-TB represents a significant form of drug-resistant TB from a
public health standpoint, since its resistance to the first-line drugs used
for therapy complicates finding adequate therapy regimens that will control
the bacilli's growth. Treatment
of drug-resistant TB is determined on a case-by-case basis, using information
from the patient's medical history and drug susceptibility testing. The
recommended course of treatment will vary depending on the drugs to which the
bacilli are susceptible. Compared to conventional TB drug therapy, MDR-TB, in
general, requires more complex interventions, longer hospitalization and more
extensive laboratory monitoring. The risk of death from such infections is
markedly increased. For example, from January 1990 through September 1992,
the CDC investigated eight outbreaks of MDR-TB. In these outbreaks, 253
patients were infected, of whom approximately 75 % died (Ex. 3-38-A). Many of
these were immunocompromised due to infection with HIV. The interval from the
time of TB diagnosis to the time of death ranged from 4 to 16 weeks, with a
median time of 8 weeks. Factors Affecting Transmission A
number of factors can influence the likelihood of acquiring a tuberculosis
infection: (1) The probability of coming into contact with an individual with
infectious TB, (2) the closeness of the contact, (3) the duration of the
contact, (4) the number of tuberculosis bacilli in the air, and (5) the
susceptibility of the uninfected individual. Several environmental conditions
can influence the likelihood of infection. For example, the volume of shared
air space, the amount of ventilation, the presence or absence of sunlight,
the humidity and the crowded nature of the living quarters. These types of
factors will affect the probability of acquiring a tuberculosis infection
after being exposed to an individual with infectious TB. MDR-TB is not more
contagious than drug-susceptible forms of the disease. However, due to time
delays in diagnosing resistance patterns and initiating adequate treatment,
individuals with active MDR-TB may remain infectious for longer periods of
time. Consequently, the likelihood that they will infect other noninfected
individuals is increased. Once
infection occurs, other factors may influence the probability of progressing
to the active form of disease. As previously discussed, 10 % of immunocompetent
adults infected with TB develop active TB. Three to five percent of untreated
immunocompetent adults develop active TB within the first year after
infection (Ex. 7-50, pg. 30; 7-52). Thus, recently infected individuals have
the highest risk of developing active TB. This risk is increased for
individuals whose immune system is impaired (e.g., persons being
treated with immunosuppressive or glucocorticoid drugs, persons with chronic
conditions such as asthma or emphysema or persons infected with the HIV). The
probability of developing active disease can also be influenced by other
conditions that may alter immune function such as overall decreased general
health status, malnutrition, and increasing age. The
resurgence of TB in the United States from 1985 to 1992 has been attributed
to a number of interacting factors: (1) The inadequate control of disease in
high prevalence areas; (2) the increase in poverty, substance abuse, poor
health status and crowded substandard living conditions; and (3) the growing
number of inmates, residents of homeless shelters, elderly persons in
long-term care facilities, persons with HIV infection and immigrants from
countries with a high prevalence of TB infection (Ex. 7-50). This increase
has begun to decline, with the 1995 case levels approaching the 1985 levels. However,
a main reason for this decrease is the implementation of TB control measures,
like those proposed in this standard, in selected areas of the country such
as New York City. OSHA believes that implementation of such measures is
necessary to prevent a resurgent peak such as that observed from 1985 to 1992
and to realize the goal set out by the National Advisory Committee for the
Elimination of Tuberculosis. The following discussion describes some of the
health effects data related to occupational exposure to TB and illustrates
how the presence of TB control measures influences TB infection and disease. Occupational Exposure Exposure
to TB in the health care setting has long been considered an occupational
hazard. With the steady decline in reported TB cases from 1953 to 1985, some
of the concern for occupational exposure and transmission also declined. However,
from 1985 to 1992 the number of reported cases of TB increased. In addition,
in recent years, several outbreaks of TB among both patients and staff in
hospital settings have been reported to the CDC. These outbreaks have been
attributed to several factors: (1) Delayed recognition of active TB cases,
(2) delayed drug susceptibility testing, (3) inadequate isolation of
individuals with active TB (e.g., lack of negative pressure
ventilation in isolation rooms, recirculation of unfiltered air, and allowing
infectious patients to freely move in and out of isolation rooms), and (4)
performance of high-risk procedures on infectious individuals under
uncontrolled conditions (Ex. 7-50). In addition to hospitals, outbreaks of TB
have also been reported among the patients, clients, residents and staff of
correctional facilities, drug treatment centers, homeless shelters and
long-term health care facilities for the elderly. The factors contributing to
the outbreaks in these other occupational settings are very similar to those
factors contributing to the outbreaks in hospital settings (i.e., delayed
recognition of TB cases and poor/inadequate ventilation for isolation areas). The
following is a discussion of some of the studies that have examined
occupational transmission of TB. A large proportion of the available
information comes from exposures occurring in hospitals, in part because this
occupational setting has been recognized for many years as an area of concern
with regards to the transmission of TB. However, in more recent years this
concern has spread to other occupational settings which share factors
identified in the hospital setting as contributing to the transmission of
disease. The following sections will include a discussion of some of the
historical data from the hospital setting, as well as the more recent data
that have been developed in hospitals and other occupational settings where
the transmission of TB has occurred as a result of the recent resurgences in
the number of active TB cases. Hospitals -- Prior to 1985 Even
prior to the recent resurgence of TB in the general population, studies have
shown an increased risk of transmission of TB to <<health care workers>> exposed to individuals with
infectious TB. These studies clearly demonstrate that in the absence of
appropriate TB control measures (e.g., lack of early identification
procedures, lack of appropriate engineering controls), employees exposed to
individuals with infectious TB have become infected and in some cases have
developed active disease. In
1979, Barrett-Connor (Ex. 5-11) examined the incidence of TB among currently
practicing physicians who graduated from California medical schools from
approximately 1950 to 1979. Through mailed questionnaires, physicians were
asked to provide information that included their year of graduation from
medical school, BCG vaccination history, history of active TB, results of
their tuberculin skin testing, and the number of patients they were exposed
to with active TB within the past year. They were also asked to classify
themselves as tuberculin positive or negative and to indicate the year of the
last negative and first positive tuberculin test. Of
the 6425 questionnaires mailed out, 4140 responses were received from
currently practicing physicians. Twelve percent of the physicians had
received the BCG vaccine. Sixty-one percent of the unimmunized physicians,
who also had no history of active tuberculosis, considered themselves to be
tuberculin negative. A total of 1542 (42 %) reported themselves as having a
positive response to the tuberculin skin test, with approximately 44 percent
of those tuberculosis infections occurring before entering medical school. Of
those infections occurring before entering medical school, approximately
eight percent were reported as having been a result of contact following work
experience in the hospital prior to entering medical school. For those
physicians infected either during or after medical school, the sources of
infection were reported as occurring as a result of a known patient contact
(45.1 %), an unknown contact (41.5 %) and a non-patient contact (13.4 %). In
some cases, the nonpatient contact was reported as another physician or
another hospital employee. Approximately one in ten of the physicians
infected after entry into medical school developed active TB disease. The
authors also examined the incidence of infection, measured as the conversion
rates in those remaining negative at the end of different time intervals (e.g.,
the last three years of medical school and five to 10 years after
graduation). This examination indicated that from 1950 to 1975, there was a
78 % decrease in tuberculin conversion rates despite the expanding pool of
susceptible medical students (i.e., an increasing number of medical students
who were tuberculin negative). Yet despite this overall decrease in infection
rates over a 25 year period, tuberculin conversion rates among recent
graduates exceeded 1 % per year and age-specific infection rates among all
the physicians studied were more than twice that of the U.S. population at
comparable ages. The authors did not obtain information from the physicians
on what type of infection control measures were being used in the facilities
where they acquired their infections. A
similar analysis by Geisleler et al. (Ex. 7-46) evaluated the
occurrence of active tuberculosis among physicians graduating from the
University of Illinois medical school between the years 1938 and 1981. This
study, also conducted by questionnaire, reported that among 4575 physicians
questioned, there were 66 cases of active TB, of which 23 % occurred after
1970. Sixty-six percent of the cases occurred within 6 years of graduation. In
addition, the authors reported that in most years the incidence of TB was
greater among these physicians than the general population. Weiss
(Ex. 7-45) examined tuberculosis among student health nurses in a
Philadelphia hospital. From 1935 to 1939, before the introduction of anti-TB
drugs and the beginning of the general decline of TB in the United States,
100 % conversion rates were observed among those students who were initially
tuberculin negative. For example, of 643 students admitted, 43 % were
tuberculin negative. At the end of only 4 months, 48 % were tuberculin
positive. At the end of 1 year, 85.9 % were tuberculin positive and by the
end of the third year 100 % were positive. Of those students who converted
during their student nursing tenure, approximately 5 percent developed active
TB disease. A
decline in the rate of infection was observed over the next 36 years among
student nurses at this hospital. The rates of infection were followed for ten
classes of student nurses from 1962 to 1971. The students had little contact
with patients during their first year but spent 4 weeks of their second year
of training on the tuberculosis wards. Among those students initially
tuberculin negative, the average conversion rate was 4.2 % over the nine year
period, ranging from 0 to 10.2 %. Of the students who converted, 0.6 %
developed active TB disease. The authors attributed the decreases in
conversion rates to not only the general decrease in TB disease in the
community, but also to the increased efficiency of surveillance of patients
entering the hospital for the early identification of potential cases of TB
and the increased efficiency of isolation for TB patients. Despite the
dramatic decreases in conversion rates among these student nurses, conversion
rates were observed at levels as high as 10 % for a given year, indicating
that while the infection rates had decreased substantially since 1939, there
still remained a significant amount of occupational transmission of TB in
1971. Moreover, this study shows that short term exposure, i.e., 4 weeks, is
capable of infecting hospital employees. Similar
rates of conversion among hospital employees initially tuberculin negative
were observed in a 1977 study by Ruben et al. (Ex. 7-43) which
analyzed the results of a tuberculin skin testing program 31 months after its
inception at a university hospital in Pittsburgh. Of 626 employees who were
tested twice with the tuberculin skin test, 28 (4.5 %) converted from
negative to positive. The employees were classified as either having a
"presumed high degree of patient exposure" or a "presumed low
degree of patient exposure". Employees presumed to have high patient
exposure included nurses, X-ray and isotope laboratory personnel and central
escort workers. Employees presumed to have low exposure included secretaries,
persons in housekeeping and dietary work, and business office, laundry and
central supply personnel. The rates of conversion for employees with presumed
high exposure (6 %) and for employees with presumed low exposure (8 %) were
not significantly different. However, this study excluded physicians and
medical and nursing students. These groups of employees would also presumably
have had high exposure to patients since they are often the hospital staff
most directly involved in administering patient care. Had these employees
been included the number of conversions among employees with presumably high
exposure may have been significantly increased. The
study was not designed to determine the source of exposure for any of the
employees who converted. However, the authors suggested that the high level
of conversions among those employees with presumed low exposure to patients
may have resulted from exposures at home. A majority of this group was
comprised of housekeeping staff who were of low socio-economic status. The
authors also suggested that unrecognized cases of tuberculosis may be playing
an important role in the occupational transmission of TB in the hospital. Unrecognized
cases of TB have been shown to play a significant role in the outbreak of TB
in a general hospital. In 1972, Ehrenkranz and Kicklighter (Ex. 5-15)
reported a case study in which 23 employees converted after exposure to a
patient with an undetected case of tuberculosis bronchopneumonia. In this
study, the source case was an individual who was admitted to the emergency
room with pulmonary edema. Upper lobe changes of the lung were noted in the
chest X-ray, and TB was mentioned as a possible cause. However, no sputum
cytology was conducted. The patient spent 3 hours in the emergency room, 57
hours in a private room and another 67 hours in intensive care until his
death. Treatment of the patient included intubation with an endotracheal tube
and vigorous nasotracheal suctioning. It was only upon microscopic
examination of tissue samples of the lung and lymph nodes after the autopsy
of the patient that tuberculosis mycobacteria were detected. Employees
who worked in the emergency room, the intensive care unit and on the floor of
the private room (NW 3) and who were also tuberculin negative before the
admission of the patient, were retested to detect possible conversion. In
addition, 21 initially tuberculin negative employees on an adjacent floor (NW
2) were also retested. Of the 121 employees tested, 24 were identified as
having converted to positive status (21 working on NW 3, 2 working in the
intensive care unit and 1 working on NW 2). No conversions were observed
among those working in the emergency room. The
employees who were retested were classified as either having close contact (e.g.,
providing direct care), little contact (e.g., more distant contact),
unknown contact (e.g., no record or recollection of contact) or
indirect contact (e.g., in the same room a day or two after the
patient's stay). Conversions occurred in 50 % (13 of 26) of those employees
with close contact, 18.5 % (6 of 33) of those with little contact, 21.4 % (3
of 14) of those with unknown contact and 3.7 % (1 of 29) of those with
indirect contact. While
the majority of conversions seems to have occurred in those employees on NW 3
who had close or little contact, there also were employees with more distant
contact who were infected. An analysis of the ventilation of NW 3 indicated
that the central air conditioning recycled 70 % of the air with no high
efficiency filter and no record of balancing the air conditioning system,
thus allowing the air from the patients' rooms to mix with and return to the
central corridor air. In addition, smoke tube tests detected direct air flow
from the patients' rooms to the hall corridor. Perhaps the more important
factor was that the patient was not diagnosed with infectious TB until after
his death, by which time he had already infected 24 employees. These
earlier studies illustrate that despite the decrease in TB morbidity since
the advent of anti-tuberculosis drugs in the 1940's, occupational
transmission of TB continues to be a problem. In addition, while many
improvements have been made in infection control procedures for TB in
hospitals, evidence of occupational transmission of TB continues to be
reported. Hospitals -- 1985 to Present As
discussed above, the transmission of TB has been well established as an
occupational hazard in the hospital setting. Many improvements were made in
infection control practices. However, the resurgence in TB from 1985 to 1992
has brought to attention the fact that many TB control measures have not been
implemented or have been inadequately applied. These studies demonstrate that
TB continues to be an occupational hazard in the hospital setting. In
addition, similar to the earlier studies, the more recent data show that the
lack of early identification procedures and the lack of appropriate
ventilation, performance of high-hazard procedures under uncontrolled
conditions and the lack of appropriate respiratory protection have resulted
in the infection of employees and in some cases the development of active
disease. The more current outbreaks are even more troubling due to the
emergence of multidrug-resistant forms of TB disease, which in some cases
have resulted in fatality rates approaching 75 %. In
a 1985 study, Chan and Tabak (Ex. 7-3) investigated the risk of TB infection
among physicians in training at a Miami hospital. In this study a survey was
conducted among 665 physicians in training who were in their first four years
of postgraduate training. Only 404 responded to the survey, of which 13 were
illegible. Another 72 were excluded because they had received the BCG
vaccination. Of the remaining 319 physicians, 55 were tuberculin positive. Of
the 279 who were tuberculin negative at the beginning of their post graduate
training, 15 were excluded because they had more than four years of training
and 43 were excluded because they had not had repeat skin tests. Of the 221
remaining available for evaluation, 15 converted to positive tuberculin
status, of which two developed active disease. The
overall conversion rate for these physicians was 6.79 %. In addition, the
authors observed a positive correlation between the rate of conversion and
the duration of postgraduate training. The conversion rate increased with the
duration of training, beginning with a cumulative percentage of conversion of
2.06 % in the first year, 8.62 % in the 2nd year, 11.11 % in the third year
and 14.29 % in the fourth year, resulting in a linear conversion rate of 3.96
% per year. As noted by the authors, this linear increase suggests the
hospital environment as the source of the infection. In addition, the
prevalence rate of conversions in the hospital (17.24 %) was much higher than
would have been expected in the community for individuals of the same age. The
authors suggested that these high rates of conversion may have been a result
of the fact that the hospital in this study encounters 5 to 10 times more
active TB cases than most other urban hospitals. In addition, the physicians
in training also are expected to be the first in line to perform physical
evaluations and evaluate body fluids and secretions. While the authors did
not go into detail about what, if any, TB infection control precautions were
taken by these physicians in training, they did note that the evaluation of
body fluids and secretions was often done in poorly ventilated and
ill-equipped laboratories. Increased
rates of conversion were observed among employees in a New Orleans hospital
in a 1986 study by Ktsanes et al. (Ex. 7-6). Similar to Miami, New Orleans
also has a high rate of TB in the community. This study examined the skin
test conversions among a cohort of 550 new employees who were followed for
five years after assignment to the adult inpatient services. Of these 550
employees who were initially tuberculin negative, 17 converted to positive
status over the five-year study period, resulting in an overall five-year
cumulative conversion probability of 5.2 %. Regression
analyses were done to examine potential contributing factors. Factors
examined in the regression model included race, job, age at employment, and
department. Only race (i.e., black vs. white employees) and job (i.e.,
nursing vs. other jobs) were found to be associated with skin test
conversion. To further examine the potential job effect, conversions among
blacks in nursing and blacks in other jobs were compared. Overall, the
cumulative probability of converting was higher among blacks in nursing,
suggesting that the acquired infections resulted from employment at the
hospital rather than from the community at large. The authors thus concluded
that there is an increased risk of occupational transmission of TB in
TB-prevalent areas for those in close patient contact jobs. In
1989, Haley et al. (Ex. 5-16) conducted a case study of a TB outbreak
among emergency room personnel at a Texas hospital. In this study, a 70 year
old male diagnosed with pulmonary TB and undergoing treatment was diverted,
due to respiratory arrest, to Parkland Memorial Hospital while in route to
another hospital. The man was admitted to the emergency room for
approximately 4 hours until he was stabilized. Afterwards, the patient was
placed in an intensive care unit, where he remained for 2 months until his
death. Six
cases of active TB developed among emergency room employees after exposure to
the TB patient, i.e., the index case. Five of these were among nurses who
recalled contact with the index patient and a sixth case was an orderly who
may have been infected from one of the employee TB cases. In addition, a
physician exposed while administering treatment in the intensive care unit
also developed active disease. Skin
test conversions were evaluated for the 153 employees of the emergency room. Of
112 previously negative employees, 16 had positive skin tests, including 5
nurses diagnosed with active TB. Fifteen of the conversions were a result of
exposure to the index case. Skin tests were also evaluated for physicians in
the intensive care unit. Of 21 resident physicians, two of whom had intubated
the index patient, five had newly positive reactions to the tuberculin skin
tests. One of the remaining three residents later developed active disease. The
authors attributed the outbreak to several factors. First, the index case had
a severe case of pulmonary TB in which he produced copious amounts of sputum.
Second, sixty percent of the emergency room air was recirculated without
filtration adequate to remove TB bacilli, allowing for the recirculation of
contaminated air. Finally, employees in the emergency room were provided
surgical masks that were ineffective for protecting against transmission of
airborne TB droplet nuclei. This study illustrates that the lack of effective
measures for controlling TB transmission can result in the infection and
development of active disease in a relatively high number of employees even
after exposure to only one case of active TB. Similarly,
the lack of effective controls while performing high-hazard, cough-inducing
procedures on individuals with infectious TB has also been shown to result in
an increased risk of TB transmission. A 1990 report by Malasky et al. (Ex.
7-41) investigated the potential for TB transmission from high-hazard
procedures by examining tuberculin skin test conversion rates among pulmonary
physicians in training. In this study, questionnaires were sent annually, for
3 years, to training programs located in the top 25 cities for TB in 1983. The
purpose of the study was to compare the conversion rates of pulmonary disease
fellows to the conversion rates of infectious disease fellows. It was
presumed that both groups have contact with patients with TB but that
pulmonary disease fellows are usually more involved with invasive procedures
such as bronchoscopies. Information requested on the questionnaires included
the type of fellowship (i.e., pulmonary or infectious disease fellow), prior
tuberculin skin test status, tuberculin status by the Mantoux technique at
the end of the 3 year fellowship program, history of BCG vaccination, age,
sex and ethnicity. In addition, the pulmonary disease fellows were asked to
give information on the number of bronchoscopies they performed and their use
of masks during the procedure. Fourteen
programs submitted data that were usable. Only programs that had both
pulmonary and infectious disease fellows in the same system were used for the
study. From this information, it was observed that 7 of 62 (11 %) of the
pulmonary fellows at risk converted their tuberculin skin test from negative
to positive during the two year training period. In contrast, only 1 of 42
(2.4 %) of the infectious disease fellows converted. The expected conversion
rate from previous surveys was 2.3 %. In addition, the pulmonary disease
fellows were grouped according to tuberculin skin status. Skin test status
was evaluated for its relationship to the number of bronchoscopies performed
and the pattern of mask usage. No correlations were found with these factors
and tuberculin skin status at the end of the fellowship. The authors
suggested that the lack of correlation between mask usage during
bronchoscopies and skin test conversion implies that masks worn by physicians
may be inadequate. While little information was presented to evaluate this
suggestion, the study does suggest that high-hazard procedures such as
bronchoscopies that induce coughing, performed under uncontrolled conditions,
present a risk for TB transmission. Pearson
et al. (1992)
conducted a case-control study to investigate the factors associated with the
development of MDR-TB among patients at a New York City hospital (Ex. 5-24). As
a part of this study, tuberculin skin test conversion rates were compared
among <<health care
workers>>
assigned to wards where patients with TB were frequently admitted (e.g.,
HIV unit, general medical ward, respiratory therapy) or rarely admitted
(operating room, orthopedic ward, outpatient clinic, psychiatry ward). In
addition, infection control procedures and ventilation systems were
evaluated. Of
79 <<health care
workers>>
who were previously negative, 12 (15 %) had newly positive skin tests. Those <<health care
workers>>
who were assigned to wards where patients with TB were frequently admitted
were more likely to have skin test conversions (i.e., 11 of 32) than <<health care
workers>>
assigned to wards where patients with TB were rarely admitted (i.e., 1 of
47). Evaluations
of the infection control procedures and ventilation systems revealed that
patients who were receiving isolation precautions for suspected or confirmed
TB were allowed to go to common areas if they wore a surgical mask. However,
many of the patients did not keep their masks on when out of their rooms. In
addition, neither the isolation rooms nor rooms used for cough-inducing
procedures were under negative pressure, thus allowing contaminated air to
exhaust to the adjacent corridors. Edlin
et al. (1992)
(Ex. 5-9) investigated an outbreak of MDR-TB in a New York hospital among
patients with acquired immunodeficiency syndrome (AIDS). This study compared
the exposure period of AIDS patients diagnosed with MDR-TB to the exposure
period of AIDS patients with drug-susceptible TB. The date of diagnosis was
defined as the date the sputum sample was collected from which tuberculosis
bacteria were grown in culture. Patients were assumed to be infectious two
weeks before and two weeks after the date of diagnosis. The period of
exposure was the period in which the patient may have been infected with TB. Because
of the rapid progression from infection to disease, the exposure period was
defined as 6 months preceding the date of diagnosis, excluding the last two
weeks. The
patients with MDR-TB were found to be more likely to have been hospitalized
during their exposure periods. Those who were hospitalized were more likely
to have been on the same ward and on the same day as a patient with
infectious TB and were more likely to have been near a room housing an infectious
patient. Examination of the infectious patients' rooms revealed that only 1
of 16 rooms had negative pressure. Based on this evidence, the authors
concluded that the observed cases of MDR-TB were a likely result of
infections acquired in the hospital (i.e., primary TB) rather than as a
result of the reactivation of infections acquired in the past. The authors
attributed these nosocomial infections to the lack of adherence to
recommended infection control procedures. While
the primary focus of this study was to investigate the transmission of TB
among patients, the increased likelihood of nosocomial infections among
patients in the hospital would seem equally likely to apply to <<health care
workers>>
working in the same environment. A survey of tuberculin skin test conversions
revealed an 18 % conversion rate for <<health care workers>> who previously had negative skin
tests and were present during this outbreak of MDR-TB. Although no statistics
were reported, the authors stated that the pattern of skin test conversions
suggested an ongoing risk over time rather than a recent increase during the
outbreak period. Based
on an earlier 1990 report from the CDC (Ex. 5-22), Beck-Sague et al.
1992 (Ex. 5-21) conducted a case-control study to investigate an outbreak of
MDR-TB among the staff and patients in a HIV ward and clinic of a Miami
hospital. As part of the overall study the authors compared the skin test
conversion rates of <<health care workers>> in the HIV ward and clinic to the skin test
conversion rates of <<health care workers>> in the thoracic surgery ward
where TB patients were rarely seen. In addition, the authors also evaluated
the relationship between the presence of patients with infectious MDR-TB and
patients with infectious drug-susceptible TB on the HIV ward and the risk of
skin test conversion among the HIV ward <<health care workers>>. Infection control procedures in
the HIV ward and clinic were also examined. All
patients with suspected or confirmed TB were placed in isolation. However,
some patients whose complaints were not primarily pulmonary and whose chest
X-rays were not highly suggestive of TB were not initially suspected of TB
and were not placed in isolation. Patients who were admitted to isolation
rooms were allowed to leave TB isolation 7 days after the initiation of
chemotherapy regardless of clinical or bacteriologic response. Thus, in some
instances, patients with MDR-TB were allowed to leave isolation while they
were still infectious, before drug resistance was recognized. In addition,
patients in isolation rooms sometimes left the doors open, left their rooms,
and/or removed their masks while outside their rooms. Patients with TB who
were readmitted to the HIV ward and who were receiving anti-TB drugs were not
admitted to isolation. In some cases, these patients were later found to have
infectious MDR-TB. An
environmental assessment of the ventilation revealed that among 23 rooms
tested with smoke tubes, 6 had positive pressure and many of the rooms under
negative pressure varied from negative to positive depending on the fan
setting and whether the bathroom door was open. Aerosolized pentamidine
administration rooms were also found to have positive pressure relative to
adjacent treatment areas. In addition, the sputum induction rooms were found
to recirculate air back to the HIV clinic. Skin
test conversions were evaluated for all <<health care workers>> (i.e., nurses and clerical staff)
who tested negative on the tuberculin skin test before the outbreak period,
March 1988 through April 1990. <<Health care workers>> on the HIV ward and in the HIV
clinic exhibited a significantly higher rate of skin test conversion than <<health care
workers>>
on the thoracic surgery ward (e.g., 13/39 vs. 0/15). Ten of the
conversions occurred among the 28 <<health care workers>> in the HIV ward. Among these <<health care
workers>>,
the authors reported a significant correlation between the risk of infection
in <<health care
workers>>
and the number of days that patients with infectious MDR-TB were hospitalized
on the HIV ward. No correlation was observed between the risk of infection
among <<health care
workers>>
on the HIV ward and the number of days that patients with infectious
drug-susceptible TB were hospitalized on the ward. Based
on skin test conversions and the evaluation of infection control practices in
the HIV ward and clinic, the authors concluded that the <<health care
workers>>
most likely were infected by patients on the HIV ward with MDR-TB. The
factors most likely contributing to this increased risk of infection
included: (1) The prolonged infectiousness and greater number of days that
patients with infectious MDR-TB were hospitalized, (2) the delayed
recognition of TB and failure to suspect infectious TB in patients receiving
what proved to be ineffective anti-TB treatment, (3) the inadequate duration
of, and lapses in, isolation precautions on the HIV ward, and (4) the lack of
negative pressure ventilation in isolation and treatment rooms. While the
evidence in this study primarily points to the transmission of MDR-TB from
patients to <<health care workers>>, many of the problems identified with
infection control procedures and ventilation would also increase the risk of
acquiring drug-susceptible TB. In
addition to MDR-TB outbreak investigations in Miami, in 1993 the CDC reported
an outbreak in New York City in which <<health care workers>> became infected after being
exposed to patients with MDR-TB (Ex. 6-18). In this investigation, for the
period December 1990 through March 1992, 32 patients were identified with
MDR-TB. Twenty-eight of these patients had documented exposure to an
undiagnosed infectious MDR-TB patient while all of them were in the HIV ward
of the hospital. During
November 1991, <<health care workers>> who were assigned to the HIV inpatient unit
and who were also previously negative on the tuberculin skin test, were given
an additional skin test. Of 21 <<health care workers>> tested, 12 (57 %) had converted
to positive status (7 nurses, 4 aides and 1 clerical worker). None of the <<health care
workers>>
had used respiratory protection. An
investigation of infection control practices revealed that of 32 patients
with MDR-TB, 16 were not initially suspected of TB and in these cases
isolation precautions either were not used or were instituted late during the
patients' hospitalization. In addition, patients who were admitted to
isolation frequently left their rooms and when in their room the doors were
frequently left open. Moreover, all rooms were found to be under positive
pressure relative to the hall. Thus, similar to the findings in Miami, the
results of this study indicate that the inability to properly isolate
individuals with MDR-TB and also the use of inadequate respiratory protection
may increase the risk of infection among <<health care workers>>. Undiagnosed
cases may also present a significant source for occupational transmission of
TB. A case study by Cantanzaro (Ex. 5-14) described an outbreak of TB
infection among hospital staff at a San Diego hospital where the hospital
staff were exposed to a single patient with undiagnosed TB. In this case, a
64 year old man suffering from generalized seizures was transferred from a
local jail to the emergency room and later admitted to a four bed
intermediate care unit. While in the intermediate care unit he was treated
with anticonvulsants but continued to have seizures accompanied with
vomiting. He was therefore placed in intensive care where he underwent a
variety of procedures including bronchoscopies and endotracheal intubation. During
his stay, he received frequent chest therapy and suctioning. Three sputum
samples were taken from the patient for smears and cultures. All AFB smears
were negative. However, two cultures were positive for tuberculosis. Despite
the presence of positive cultures the patient was not diagnosed with active
TB. The problem was not recognized until a physician on staff later developed
symptoms of malaise and slight cough and requested a tuberculin skin test and
was found to be positive. Because the physician had been tuberculin negative
8 months earlier, a contact investigation was initiated. As a part of this
investigation, all employees who previously had negative tuberculin tests and
who also worked in the intermediate and intensive care units where the
patient had been treated were given repeat skin tests. Of 45 employees who
previously had negative tuberculin skin tests, 14 (31 %) converted to
positive status (6 physicians, 3 nurses, 2 respiratory therapists and 1
clerk). Ten of these conversions were among the 13 previously tuberculin
negative staff members who were present at the time bronchoscopies were
conducted (10/13=76.9 %). Four of the conversions were among 32 susceptible
staff members who were not present at the bronchoscopies (4/32=12.5 %). The
author thus concluded that being present during the bronchoscopy of the
patient was a major risk factor in acquiring the TB infection. However, the
evidence did not show a significant correlation between skin test conversion
and the type of exposure, i.e., close (administered direct contact) versus
casual (in the room) contact. Thus, people who were present in the room
during the bronchoscopy had an equal risk of infection as those administering
direct patient care, presumably, as the author suggests, because droplet
nuclei can disperse rapidly throughout the air of a room. Similarly,
Kantor et al. (Ex. 5-18) reported an outbreak of TB infection among
hospital staff exposed to a single undiagnosed case of TB. The index case in
this investigation was a 50 year old man who was admitted for lung cancer and
was receiving chemotherapy, steroids and radiation treatment. After a month
of treatment, the patient complained of a cough and chest pain and was found
to have emphysema requiring additional drug treatment and a chest tube. However,
even after the emphysema resolved, the patient complained of weakness, loss
of appetite and fever. A sputum culture and smear were conducted for
mycobacteria and found to be negative. Lung X-rays were found to be irregular
but were attributed to the lung cancer. Upon his death the autopsy revealed
extensive necrosis in the lung but tuberculosis was not suspected. Thus, no
cultures for mycobacteria were performed and no infection control procedures
were initiated. It was only upon histological examination of tissue samples
one month later that the presence of TB was confirmed. Five months later one
of the staff performing the autopsy developed active TB. His only history of
exposure was to the index case. As
a result, a contact investigation was initiated for hospital personnel who
had shared air with the patient during his stay, including the autopsy staff.
Of susceptible hospital staff (i.e., those not previously found to react
positive to the tuberculin skin test), infection developed in 9 of 56 (16 %)
exposed employees (4 autopsy staff, 4 nursing staff and 1 radiology staff). Only
3 of 333 unexposed personnel were found to have converted to positive
tuberculin status at the hospital during the same period of investigation,
thus indicating a 17.8 fold increase in the infection rate for the exposed
group. Undiagnosed
cases of TB at time of autopsy were also indicated as the likely cause for
development of active TB among staff and students in an autopsy room in a
Swedish hospital (Ex. 5-19). In this study, three medical students and one
autopsy technician, who were present during the autopsy of a patient with
previously undiagnosed pulmonary TB, developed active TB. Both the medical
students and the autopsy technician had previously received the BCG vaccine
but none had any other known contact with a tuberculosis subject. Thus, it
was concluded that the tuberculosis infections were most likely to have been
transmitted during the autopsy. The findings of this study further illustrate
the risks that undiagnosed cases of active TB present to <<health care
workers>>. The
lack of recognition of an active case of TB often results in a failure to
initiate appropriate infection control procedures and provide appropriate
personal protective equipment. In addition, this study illustrates that,
while TB is most often transmitted by individuals with infectious pulmonary
TB who generate droplet nuclei when they cough or speak, the autopsy
procedures on deceased individuals with pulmonary TB may also aerosolize
bacteria in the lungs and generate droplet nuclei. Exposure
during autopsy procedures was also suspected as a possible route of TB
transmission in an upstate New York Medical Examiner's Office (Ex. 7-152). This
Medical Examiner's Office conducted autopsies on deceased inmates from
upstate New York prisons. In 1991, the same year that an outbreak of MDR-TB
occurred among inmates from an upstate New York prison, the Medical
Examiner's office conducted autopsies on 8 inmates with TB, six of whom had
infectious MDR-TB at death and who were also HIV positive and had
disseminated TB disease. Skin
tests were administered to employees who had worked for at least one month
during 1991 at the Medical Examiner's Office. Among 15 employees who had
originally tested negative on a baseline skin test, 2 were found to have
converted. These two employees worked as morgue assistants and had recent
documented exposure to persons with extensive disseminated MDR-TB. No
potential exposure to TB outside the Medical Examiner's Office could be
found. The
autopsy area of the office had a separate ventilation system. However, air
was returned to a common air plenum, allowing the air to mix between the
autopsy area and other areas of the office. In addition, the autopsy room was
found to be at positive pressure relative to the adjacent hallway. Employees
performing or assisting at autopsies on persons known to be infected with HIV
were required to wear plastic gowns, latex gloves and surgical masks. Particulate
respirators were not required until November of 1991, after the installation
of germicidal UV lamps. However, this was after the last MDR-TB autopsy. This
study suggests that the conversion of these two morgue assistants occurred as
a result of exposure to aerosolized M. tuberculosis resulting from
autopsy procedures, either as a result of participation in an autopsy in the
autopsy area or from exposure to air contaminated with aerosolized M.
tuberculosis that was exhausted into other areas of the Medical
Examiner's Office. In
addition to autopsy procedures, other procedures, such as the irrigation of
abscesses at sites of extrapulmonary TB, can result in the generation of
droplet nuclei. An outbreak investigation in an Arkansas hospital (Ex. 5-17)
reported the transmission of TB among hospital employees exposed to a patient
with a tuberculous abscess of the hip and thigh. In this study, the source
case was a 67 year old man who was admitted to the hospital with a fever of
unknown origin and progressive hip pain. The patient did not present any
signs of pulmonary TB; however, the examination of soft tissue swelling in
the hip area revealed an abscess that required drainage and irrigation. Due
to the suspicion of TB, specimens for AFB smear and culture were obtained and
the patient was placed in isolation. While in isolation, drainage from the
abscess continued and irrigation of the abscess cavity was initiated on an
8-hour schedule. After four days, acid fast bacilli were observed in the AFB
smears and TB therapy was begun. The patient remained in isolation until his
death except for three days that he spent in the Intensive Care Unit (ICU)
due to high fever. An
investigation of skin test surveys among the hospital employees revealed 55
skin test conversions among 442 previously nonreactive employees and 5
conversions among 50 medical students. In addition, 5 of the employees who
had conversions also had active TB, including one who developed a tuberculous
finger lesion at the site of a needle-stick injury incurred during the
incision and drainage of the patient's abscess. All the skin test converters,
except for two, recalled exposure to the source case. Of the 442 susceptible
employees, 108 worked at least one day on one of the floors where the patient
stayed (i.e., the surgical ward, the medical floor of the patient's room and
the ICU). Four (80 %) of 5 surgical suite employees who had direct contact
with the patient through their assistance with the incision and irrigation of
the patient's abscess had skin test conversions. In addition, 28 (85 %) of 33
employees on the general medical floor and 6 (30 %) of 20 ICU employees had
skin test conversions. All those employees converting recalled exposure to
the patient, some of whom had no direct contact with the patient. Environmental
studies revealed that two of the areas in which the patient stayed during his
hospitalization did not have negative pressure. The isolation room was under
positive pressure relative to adjacent rooms and the corridor. In addition,
the patient's cubicle in the ICU had neutral pressure relative to the rest of
the ICU. Employees in these two areas had skin test conversions even in cases
where there was no direct patient contact. The lack of negative pressure was
thought to have significantly contributed to the dispersion of droplet nuclei
generated from the irrigation of the tuberculous abscess. In the surgical
ward, air was directly exhausted to the outside. However, all employees
present in the surgical ward when the patient was being treated had direct
contact with the patient. There was no indication that the surgical staff had
taken any special infection control precautions or had worn any personal protective
equipment. Thus,
similar to other outbreak investigations, the lack of appropriate ventilation
and respiratory protection stand out as the key factors in the transmission
of TB to employees who are exposed to individuals with infectious TB. Moreover,
this particular case study demonstrates that certain forms of extrapulmonary
TB in conjunction with aerosolizing procedures, e.g., the irrigation
of a tuberculous abscess, have the potential for presenting significant
airborne exposures to M. tuberculosis. Other
aerosolizing procedures have also shown evidence of presenting airborne
exposures to M. tuberculosis. For example, tissue processing was
associated with the skin conversion of two pathologists working at a
community hospital in California (Ex. 6-27). In this case study, after
autopsy, a 62 year old man who had died from bronchogenic carcinoma was
discovered to have a caseating lung lesion. A stain revealed a heavy
concentration of acid-fast bacilli, which were identified in culture as M.
tuberculosis. As a result, a contact investigation was initiated. This
investigation found twenty employees who had contact with the patient,
including two pathologists and a laboratory assistant. All were given a
tuberculin skin test and found to be negative. However, after follow-up skin
testing three months later, the two pathologists had converted. Other than
contact with the source case, the two had no other obvious sources of
infection. One of the pathologists had been present at the autopsy. Both
pathologists were present when the frozen lung sections were prepared. During
this process, the lung tissue was sprayed with a compressed gas coolant,
which created a heavy aerosol. Masks were not routinely worn during this
tissue processing. The investigators suspected that this aerosol promoted the
transmission of TB and was the likely cause of the observed infections. While
much of the health effects literature has focused on outbreaks of TB or
MDR-TB, a more recent study investigated the status of infection control
programs among "non-outbreak" hospitals (Ex. 7-147). Investigators
from the Society of Health care Epidemiology of America (SHEA) and the CDC
surveyed members of SHEA to assess compliance in the respondents' hospitals
with the 1990 CDC Guidelines for Preventing the Transmission of TB in Health
Care Facilities for the years 1989 to 1992. The survey included questions on
tuberculin skin testing programs (e.g., frequency of testing,
positivity at hire, and percent newly converted), AFB isolation capabilities (e.g.,
negative pressure, air changes per hour, HEPA filtration) and respiratory
protection. The
survey showed that of the 210 hospitals represented by the SHEA members'
survey results, 193 (98 %) admitted TB patients from 1989 to 1992, 40 % of
which had one or more patients with MDR-TB. In addition, the proportion of
hospitals caring for drug susceptible TB patients rose from 88 % to 92 % and
the proportion of hospitals caring for MDR-TB patients rose from 5 % to 30 %.
While the number of hospitals caring for TB patients increased, the majority
of those hospitals cared for a small number of patients. In 1992,
approximately 89 % of the hospitals reported 0 to 25 patients per year, while
approximately 5 % reported greater than 100 patients per year. Few
hospitals reported routine tuberculin skin testing for each of the years
surveyed. For example, while 109 (52 %) of the responding hospitals reported
tuberculin skin test results for at least one of the years from 1989 to 1992,
only 63 (30 %) reported results for each of these years. When examining the
conversion rates over time from 1989 to 1992, the investigators limited their
analysis to the 63 hospitals reporting skin test data for each of these 4
years. Among these hospitals the median percentage of employees newly
converting to positive skin test status remained constant over the 4 year
period at approximately 0.34 % per year (i.e., 3/1000 per year). However,
when including all hospitals in the analysis, from 1989 to 1992, the number
of hospitals reporting conversion rates increased from 63 to 109 and the
conversion rates increased from 0.26 % (i.e., 2/1000) to 0.50 % (i.e.,
5/1000). With
regard to AFB isolation capabilities, 62 % of 181 responding hospitals
reported that they had isolation facilities consistent with the 1990 CDC TB
Guidelines (i.e., single-patient room, negative pressure, air directly
exhausted outside, and ?6 air changes per hour). Sixty-eight
percent of the reporting hospitals had isolation facilities meeting the first
three of these recommendations. For respiratory protection, the majority of <<health care
workers>>
in the hospitals used surgical masks. However, there was an increase in the
use of dust-mist or dust-mist-fume respirators. The use of dust-mist
respirators increased from 1 to 13 % from 1989 to 1992 and the use of
dust-mist-fume respirators increased from 0 to 10 % for the same period. The
only use of high efficiency particulate air (HEPA) filter respirators was by
bronchoscopists and respiratory therapists at 4 hospitals. As
a second phase of this investigation, the survey responses were analyzed to
determine the efficacy of the TB infection control programs among the member
hospitals participating in the survey (Ex. 7-148). In this analysis, the
reported conversion rates were compared to reported infection control
measures (i.e., AFB isolation capabilities and respiratory protection). For
purposes of comparison, hospitals were categorized as having either less than
or ?6 TB patients, less than or ?437 beds, and admitting or not admitting
MDR-TB patients. Conversion
rates were higher among <<health care workers>> from hospitals with ?437 beds than among <<health care workers>> from smaller hospitals (0.9 % vs.
0.6 %, p#0.05). This difference was more
pronounced among "higher-risk" <<health care workers>> (i.e., <<health care workers>> including bronchoscopists and
respiratory therapists). "Higher-risk" <<health care workers>> from hospitals with 437 or more
beds had a 1.9 % conversion rate compared to a conversion rate of 0.2 % for
"higher-risk" <<health care workers>> from smaller hospitals. Similarly,
<<health care
workers>>
from hospitals where 6 or more TB patients were admitted per year had higher
conversion rates than <<health care workers>> from hospitals with fewer than 6
TB patients per year (e.g., 1.2 % vs. 0.6 %). For
hospitals with 6 or more TB patients, conversion rates also varied depending
on the level of TB infection control practices that were in place in the
hospital. For example, among hospitals with 6 or more TB patients and whose
AFB isolation capabilities included at least single-room occupancy, negative
pressure and directly exhausted air, the conversion rates among <<health care
workers>>
were lower than the conversion rates among <<health care workers>> at hospitals with 6 or more TB
patients but which did not have similar isolation capabilities (0.62 % vs.
1.83 %, p=0.03). For respiratory protection, however, no differences in
conversion rates were observed among <<health care workers>> wearing surgical masks (0.94 %)
and <<health care
workers>>
using submicron surgical masks, dust-mist respirators or dust-mist-fume
respirators (0.98 %). Very few survey respondents reported use of HEPA filter
respirators. For example, only four hospitals reported use of any HEPA
respirators, and these were not the predominant type of respiratory
protection used (Ex. 7-147). Thus, it is not possible to evaluate the
efficacy of these particulate respirators in reducing conversion rates from
the reported survey data. For
hospitals with fewer than 6 TB patients or with fewer than 437 beds, no
differences in conversion rates were reported among <<health care workers>> from hospitals that had
implemented AFB isolation capabilities such as single-room occupancy, negative
pressure, or directly exhausted air and those hospitals that had not. The
investigators suggested that this finding may support contentions that the
efficacy of TB infection control measures vary depending on characteristics
of the hospital or community exposure. However, given the small sample size
of the survey, as well as the reduced potential for exposure in hospitals
with fewer than 6 TB patients per year, it would be difficult to detect any
differences in conversion rates among <<health care workers>> from hospitals with or without
certain levels of infection control. Where more opportunity does exist for
exposure (e.g., hospitals with ?6
TB patients), this analysis does show that the implementation of TB infection
control procedures can reduce the transmission of TB among <<health care
workers>>. Hospitals -- Summary In
summary, the evidence clearly shows that in hospital settings, employees are
at risk of occupational exposure to TB. Various studies and TB outbreak
investigations have shown that employees exposed to individuals with
infectious TB have converted to positive tuberculin skin status and in some
cases have developed active disease. In these reports, a primary factor in
the transmission of TB has been a failure to promptly identify individuals
with infectious TB so that appropriate infection control measures could be
initiated to prevent employee exposure. In addition, another major factor
identified as contributing to occupational exposures was the lack or
ineffective implementation of appropriate exposure control methods (e.g.,
lack of negative pressure in isolation rooms, lack of appropriate respiratory
protection for exposed employees, performance of high-hazard procedures under
uncontrolled conditions). The lack of early identification and appropriate
control measures resulted in the exposure and subsequent infection of various
hospital employees. These employees included not only health care providers
administering direct patient care to individuals with infectious TB, but also
hospital staff providing support services to the infectious individuals,
hospital staff working in adjacent areas of the hospital using shared air, autopsy
staff and laboratory staff working with infected culture and tissue samples. Other Occupational Settings While
hospitals have been historically recognized as the primary type of work
setting where TB presents an occupational hazard, there are other work
settings where the transmission of TB presents a hazard to workers. There are
a variety of occupational settings in which workers can reasonably be
anticipated to encounter individuals with active TB as a part of their job
duties. Several work settings have been identified by the CDC where exposure
to TB presents an occupational hazard: correctional facilities, long-term
care facilities for the elderly, homeless shelters, drug treatment centers,
emergency medical services, home-health care, and hospices. Similar to the
hospital setting, these work settings have a higher number of individuals
with active TB than would be expected for the general population. Many of the
clients of these work settings have many characteristics (e.g., high
prevalence of TB infection, high prevalence of HIV infection, intravenous
drug use) that place them at an increased risk of developing active TB. These
types of work settings are also similar to hospitals in that workers at these
sites may also provide medical services and perform similar types of
high-hazard procedures that are typically done in a hospital setting. In
addition to employees who provide medical services in these other types of
work settings, there are other types of workers (e.g., guards,
admissions staff, legal counsel for prisoners) who may also be exposed to
individuals with infectious TB. Similar to hospitals, these work settings
have an over-representation of populations at high risk for developing active
TB, e.g., individuals infected with HIV, intravenous drug users,
elderly individuals, and individuals with poor nutritional status and who are
medically underserved. In addition to having a higher percentage of
individuals with TB infection and a higher percentage of individuals at an
increased risk for developing active TB, many of these work settings also
share environmental factors that facilitate the transmission of TB, such as
overcrowding and inadequate ventilation, which increases the occupational
hazard. The following discussion describes some of the studies available in
the literature that have examined the occupational transmission of TB in
other occupational settings such as those listed above. Not all the settings
listed by the CDC as places where TB transmission may be likely to occur have
been adequately studied and thus can not be included in this discussion. However,
the discussion of the following sectors clearly demonstrates that the
occupational transmission of TB is not limited to the hospital setting. Occupational
settings where there is an increased likelihood of exposure to aerosolized M.
tuberculosis present the same types of occupational hazards as have been
documented in the hospital setting. Correctional Facilities Many
correctional facilities have a higher incidence of TB cases than occur in the
general population. For example, the CDC reported that the incidence of TB
among inmates of correctional facilities was more than three times higher
than that for nonincarcerated adults aged 15-64, based on a survey of TB
cases in 1984 and 1985 by 29 state health departments (Ex. 3-33). In
particular, among inmates in the New York correctional system, the TB
incidence increased from an annual average of 15.4 per 100,000 during 1976 to
1978 to 105.5 per 100,000 in 1986 (Ex. 7-80) to 156.2/100,000 for 1990-1991
(Ex. 7-137). Similarly, in 1987, the incidence of TB among inmates in New
Jersey was 109.9 per 100,000 (approximately 11 times higher than the general
population in New Jersey) and in California the incidence of TB among inmates
was 80.3 per 100,000 (approximately 6 times higher than that for the general
population for California) (Ex. 3-33). In 1989, the CDC reported that since
1985, eleven known outbreaks of TB have been recognized in prisons (Ex.
3-33). The
increased incidence of TB in correctional facilities has been attributed to
several factors (Ex. 7-25). One, correctional facilities have a higher
incidence of individuals who are at greater risk for developing active TB. For
example, the population in prisons and jails may be dominated by persons from
poor and minority groups, many of whom may be intravenous drug users. These
particular groups may also suffer from poor nutritional status and poor
health care, factors that place them at increased risk of developing active
disease. Two, special types of correctional facilities, such as holding
facilities associated with the Immigration and Naturalization Services, may
have inmates/detainees from countries with a high incidence of TB. For
foreign-born persons arriving in the U.S., the case rate of TB in 1989 was
estimated to be 124 per 100,000, compared to an overall TB case rate of 9.5
per 100,000 for the U.S. (Ex. 6-26). In 1995, TB cases reported among the
foreign born accounted for 35.7 % of the total reported cases, marking a 63.3
% increase since 1986 (Ex. 6-34). Three, many correctional facilities have a
high proportion of individuals who are infected with HIV. The CDC reported
that in addition to the growing increase in AIDS among prisoners, the
incidence of AIDS in prisons is markedly higher than that for the U.S.
general population. In 1988, the incidence of AIDS cases in the U.S.
population was 13.7 per 100,000 compared to an estimated aggregate incidence
for state/federal correctional systems of 75 cases per 100,000 (Ex. 3-33). Individuals
who are infected with HIV or who have AIDS are at an increased risk of
developing active TB due to their decreased immune capacity. The likelihood
of pulmonary TB in individuals with HIV infection is reflected in the CDC's
Revised Classification System for HIV infection (Ex. 6-30). In this revised
classification system, the AIDS surveillance case definition was expanded to
include pulmonary TB. Moreover, X-rays of individuals infected with HIV who
have TB often exhibit radiographic irregularities that make the diagnosis of
active TB difficult (Exs. 7-76, 7-77, 7-78, and 7-79). HIV-infected
individuals may have concurrent pulmonary infections that confound the
radiographic diagnosis of pulmonary TB. In addition, it may be difficult to
distinguish symptoms of TB from Pneumocystis carinii pneumonia or
other opportunistic infections. This difficulty in TB diagnosis can result in
true cases of active TB going undiagnosed in this population. Undiagnosed TB
has been shown to be an important cause of death in some patients with HIV
infection (Ex. 7-76). Fourth, environmental conditions in correctional
facilities can aid in the transmission of TB. For example, many prisons are
old, have inadequate ventilation systems, and are overcrowded. In addition,
inmates are frequently transferred both within and between facilities, thus
increasing the potential for the spread of TB infection among inmates and
staff. This increased potential for mobility among inmates also enhances the
likelihood that inmates undergoing therapy for active disease will either
discontinue their treatment or inadequately follow their prescribed regime of
treatment. The inadequacy of their treatment may give rise not only to
relapses to an infectious state of active disease, but also potentially give
rise to strains of MDR-TB. These strains of TB have a higher incidence of
fatal outcome and are generally characterized by prolonged periods of
infectiousness during which the risk of infection to others is increased. The
high incidence of TB among the inmate population presents an occupational
hazard to the staff in these types of facilities. Recent outbreak
investigations by the CDC have documented the transmission of TB to exposed
workers. In an investigation of a state correctional facility in New York for
1991 (Exs. 6-3 and 7-136), eleven persons with TB were identified (10 inmates
and one correctional facility guard). Nine persons (8 inmates and the guard)
had MDR-TB. All eight inmates were HIV positive. The guard was HIV negative;
however, he was also immunocompromised as a result of treatment for laryngeal
cancer. Seven of the inmates and the guard died from MDR-TB. The eighth
inmate was still alive and receiving treatment for MDR-TB 2 years after being
diagnosed as having the disease. DNA analysis identified the strains of
tuberculosis bacteria from these individuals to be identical. The
investigation revealed that the source case was an inmate who had been
transferred from another prison where he had been previously exposed to
MDR-TB. He arrived at the prison with infectious TB but refused evaluation by
the infirmary staff. This inmate was placed in the general prison population
where he stayed for 6 months until he was admitted to the hospital where he
later died. However, before his hospitalization, he exposed two inmates
living in his cell block who later developed MDR-TB. These two inmates
continued to work and live in the prison until shortly before their final
hospitalization. The other inmates who subsequently developed MDR-TB had several
potential routes of exposure: social contact in the prison yard, contact at
work sites in the prison, and contact at the prison infirmary where they
shared rooms with other inmates before diagnosis with TB. The
guard who developed MDR-TB had exposure to inmates while transporting them to
and from the hospital. The primary exposure for this guard apparently
occurred when he was detailed outside the inmates' room during their
hospitalization for MDR-TB. The inmates were hospitalized in an isolation
room with negative pressure. However, upon investigation it was discovered
that the ventilation system for the room had not been working correctly and
had allowed air to be exhausted to the hospital corridors and other patient
rooms. A
contact investigation in the prison was conducted to identify other inmates
who might have been exposed during this outbreak of MDR-TB. Of those inmates
with previous negative tuberculin skin tests and without active disease
(306), ninety-two (30 %) had documented skin test conversions. There was no
tuberculin skin test program for prison staff; therefore, conversions among
prison employees could not be evaluated. The
primary factors identified as contributing to this outbreak were deficiencies
in identifying TB among transferred inmates, laboratory delays, and lapses in
isolating inmates with active TB within the facility. Inmates with symptoms
of active disease were not sent for evaluation in some cases until they
became so ill they could not care for themselves. Some of these inmates were
placed in the infirmary with other inmates until their diagnosis with TB. On
other occasions, drug susceptibility testing was not reported until after an
inmate's death, which means that appropriate patient management was not
initiated. As
a result of this outbreak, a retrospective epidemiological investigation was
conducted to examine the potential extent and spread of MDR-TB throughout the
New York State prison system during the years 1990-1991 (Ex. 7-137). This
investigation revealed that 69 cases of TB were diagnosed in 1990 and another
102 were diagnosed in 1991, resulting in a combined incidence of 156.2
cases/100,000 inmate years for 1990 and 1991 combined. Of the cases, 39 were
identified as being MDR-TB, 31 of which were shown to be epidemiologically
linked. Thirty-three of the individuals with MDR-TB never received any
treatment for MDR-TB, 3 were diagnosed at death, and 23 died before drug
susceptibility results were known. These inmates were also discovered to be
highly mobile. The 39 inmates lived in 23 different prisons while they were
potentially infectious. Twenty transfers were documented for 12 inmates with
potentially infectious MDR-TB (9 shortly before diagnosis, one after
diagnosis with TB but before diagnosis with MDR-TB, and 2 after a diagnosis
of MDR-TB). Several
factors were identified as contributing to the spread of MDR-TB throughout
the New York prison system: delays in identifying and isolating inmates,
frequent transfers without appropriate medical evaluation, lapses in treatment,
and delays in diagnosis and susceptibility testing. A
similar investigation in a California state correctional institution
identified three active cases of TB (two inmates and one employee) during
September and October 1991 (Ex. 6-5). As a result, an investigation was
commenced to determine whether transmission of TB was ongoing in the
institution. Eighteen inmates with active TB were identified. TB in 10 of
these inmates was recognized for the first time while they were in the
institution during 1991, resulting in an annual incidence of TB of 184 per
100,000, a rate greater than 10 times that for the state (17.4 per 100,000). Two
of the 10 inmates had negative tuberculin skin tests prior to their entry
into the institution. Three of the cases were determined to have been
infectious during 1991. A
review of skin test data revealed that for the 2944 inmates for whom skin
test results were available, 324 tested positive for the first time while in
the prison system. Of these, 106 were tuberculin negative before their entry
into the prison system, 96 of which occurred in the previous two years. The
employee identified as having active TB had worked as a counselor on the
prison's HIV ward, where he recalled exposure to one of the 3 infectious
inmates. This employee could recall no known exposures outside the prison. Similarly,
two other prison employees had documented skin test conversions while working
at the prison. Neither recalled exposures outside the prison; one reported
exposure to an inmate with possible TB. No
information was provided in this report as to whether any isolation
precautions were implemented at this facility. However, the investigators
concluded that their findings suggested the likelihood that transmission of
TB had occurred in the prison. Their conclusion was based on the fact that a
substantial number of skin test conversions were documented among the inmates
and that at least two inmates with active TB became infected while at the
prison. The
transmission of TB was also reported in another California prison among
prison infirmary physicians and nurses and correctional officers (Ex. 6-6). In
this investigation, an inmate with active MDR-TB spent 6 months during
1990-1991 in the infirmary. The infirmary had no isolation rooms and inmates'
cells were found to be under positive pressure. Employees occasionally
recalled wearing surgical masks when entering the rooms of TB patients. An
analysis of available skin testing data revealed that of the 21 infirmary
health care providers, only 10 had been tested twice during the period from
1987 to 1990. Of these 10, two were newly positive, one of whom had recently
converted in 1991 and had spent 5 months in the preceding year providing
health care to the source case in this investigation. Another health care
provider and a correctional officer who worked in the infirmary also were
identified as having newly converted while at the prison. There was no yearly
skin test screening, and thus their conversions could have occurred at any
time between 1987 and 1991. However, 13 other inmates were diagnosed with
pulmonary TB during that same period. An additional correctional officer who
did not work in the infirmary also was found to have newly converted. His
reported exposure occurred at a community hospital where he was assigned to
an inmate with infectious TB. The officer was not provided with any
respiratory protection. The lack of isolation precautions and the lack of
appropriate respiratory protection suggest transmission of TB from infectious
inmates in the infirmary to the prison staff, either as a result of exposure
to the source case or other inmates with pulmonary TB who were also treated
in the prison infirmary. Because of the lack of contact tracing or routine
annual screening of inmates or staff, the full extent of transmission from
the source case or other TB cases could not be determined. Thus,
similar to the evidence for the hospital setting, the evidence on
correctional facilities shows that the failure to promptly identify
individuals with infectious TB and provide appropriate infection control
measures can result in the exposure and subsequent infection of employees
with TB. These employees include the correctional facility infirmary staff,
guards on duty at the facility, and guards assigned to escort inmates during
transport to other facilities (e.g., outside health care facilities
and other correctional facilities). Homeless Shelters Tuberculosis
has also been recognized as a health hazard among homeless persons. The
growth of the homeless population in the United States since the 1980s and
the subsequent increase in the number of shelters for the homeless, furthers
heightens the concern about the potential for the increased incidence and
transmission of TB among the homeless, especially in crowded living
conditions such as homeless shelters. A
number of factors are present in homeless shelters which increase the
potential for the transmission of TB among the shelter residents and among
the shelter staff. A high prevalence of TB infection and disease is common
among many homeless shelters. This is not surprising, since the residents of
these facilities usually come from lower socio-economic groups and often have
characteristics that place them at high risk. Screening of selected clinics
and shelters for the homeless has shown that the prevalence of TB infection
ranges from 18 to 51 % and the prevalence of clinically active disease ranges
from 1.6 to 6.8 % (Ex. 6-15). The CDC estimates this to be 150 to 300 times
the nationwide prevalence rate (Ex. 6-17). In
addition to having a high prevalence of individuals with TB infection in the
shelters, many of the shelter residents possess characteristics that impair
their immunity and thus place them at a greater risk of developing active
disease. For example, homeless persons generally suffer from poor nutrition,
poor overall health status and poor access to health care. Many also suffer
from alcoholism, drug abuse and psychological stress. Moreover, a significant
portion of homeless shelter residents are infected with the HIV. In 1988, the
Partnership of the Homeless Inc. conducted a survey of 45 of the nation's
largest cities and estimated that there were between 5,000 and 8,000 homeless
persons with AIDS in New York City and approximately 20,000 nationwide (Ex.
7-55). Due to these factors, homeless shelter residents are at increased risk
of developing active disease. Thus, there is the increased likelihood that
these individuals will be infectious as a result of active disease and
thereby present a source of exposure for other homeless persons and for
shelter employees. In
addition to having factors which increase their risk of developing active TB
disease, homeless persons also are a very transient population. Because they
are transient, homeless persons are more likely to discontinue or to
erratically adhere to the prescribed TB therapy. Inadequately adhering to TB
therapy can result in relapses to an infectious state of the disease or the
development of MDR-TB. Both outcomes result in periods of infectiousness,
during which they present a source of exposure to other residents and staff. In
addition, environmental factors at homeless shelters, such as crowded living
conditions and poor ventilation, facilitate the transmission of TB. Outbreaks
of TB among homeless shelter residents have been reported. For example,
during 1990, 17 individuals with active pulmonary TB were identified among
residents of homeless shelters in three Ohio cities: Cincinnati, Columbus,
and Toledo (Ex. 7-51). In Cincinnati, 11 individuals with active TB were
identified in a shelter for homeless adults. The index case was a man who had
resided at the shelter and later died from respiratory failure. He was not
diagnosed with TB until his autopsy. Of these 11 individuals, of which the
index case was one, 7 were determined to be infectious. There was no
indication as to whether any infection control measures were in place in the
shelter. DNA analysis of 10 individual M. tuberculosis isolates showed
identical patterns. The similarity among these DNA patterns suggested that
transmission of the TB occurred in the shelter. While
the primary focus of this investigation was on the active cases reported
among the residents in this Cincinnati shelter, the risk of transmission
identified in this shelter also would apply to the shelter staff. Possible
transmission of TB infection from the infectious individuals to the shelter
staff might have been identified through tuberculin skin test conversions. However,
no tuberculin skin test information for the staff was reported in this
investigation. Tuberculin
skin testing results were reported in the investigation of a Columbus, Ohio
shelter. In this investigation, a resident of a Columbus homeless shelter was
identified with infectious pulmonary TB at the local hospital in March of
1990. The patient also had resided in a shelter in Toledo. As a result, a
city-wide TB screening was initiated from April to May 1990 among the
residents and staff of the city's men's shelters. Tuberculin skin tests were
conducted on 363 shelter residents and 123 shelter employees. Among 81
skin-tested residents of the shelter in which the index case had resided, 32
(40 %) were positive compared to 47 (22 %) of 210 skin-tested residents of
other shelters in Columbus who had positive skin test reactions. Similarly,
among 27 employees of the shelter where the index case resided, 7 (26 %) had
positive skin test reactions compared to 9 (11 %) of 85 employees in other
men's shelters. These skin test results suggest an increased risk of
transmission of TB among residents and employees of the homeless shelter
where the index case resided. However, due to the lack of baseline skin test
information among these residents and employees it is not possible to
determine when their conversion to positive status occurred and whether this
index case was their source of exposure. These results, however, do indicate
a high prevalence of TB infection among homeless residents (e.g., 40 %
and 22 %). Many of these individuals are likely to have an increased risk of
developing active TB and, as a result, they may present a source of exposure
to residents and staff. The
transmission of TB has also been observed among residents and staff of
several Boston homeless shelters (Exs. 7-75 and 6-25). From February 1984
through March 1985, 26 cases of TB were confirmed among homeless residents of
three large shelters in Boston. Nineteen of the 26 cases occurred in 1984,
thus giving an incidence of approximately 317 per 100,000, 6 times the
homeless case rate of 50 per 100,000 reported for 1983 and nearly 16 times
the 1984 case rate of 19 per 100,000 for the rest of Boston (Ex. 6-25). Of
the 26 cases of TB reported, 15 had MDR-TB. Phage typing of isolates from 13
of the individuals with drug-resistant TB showed identical phage types, thus
suggesting a common source of exposure. As a result of this outbreak, a
screening program was implemented in November 1984 over a four-night period. Of
362 people who received skin tests, 187 returned for reading, 42 (22 %) were
found to be positive and 3 were recent converters. Screening also was
reported for the shelter staff at the three homeless facilities. At the
largest of the three shelters, 17 of 85 (20 %) staff members had skin test
conversions. In the other two shelters, 3 of 15 (20 %) and 3 of 18 (16 %)
staff members had skin test conversions. Whereas
MDR-TB was primarily involved in the outbreak in Boston, an outbreak of
drug-susceptible TB was reported in a homeless shelter in Seattle, Washington
(Ex. 7-73). From December 1986 to January 1987, seven cases of TB from
homeless residents were reported to the Seattle Public Health Department. The
report of 7 individuals with active TB in one month prompted an
investigation, including: (1) A mass screening to detect undiagnosed cases,
(2) phage typing of isolates from shelter clients to detect epidemiologically
linked cases, and (3) a case-control study to investigate possible risk
factors for the acquisition of TB. A
review of the case registries revealed that 9 individuals with active TB had
been reported from the homeless shelter for the preceding year and four cases
in the year previous to that. As a result of the mass screening in late
January 1987, an additional 6 individuals with active TB were detected. Phage
typing of 15 isolates from the shelter-associated cases revealed that 6
individuals with active TB diagnosed around the time of the outbreak were of
the same phage type, suggesting that there was a predominant chain of
infection, i.e., a single source of infection. However, there also were other
phage types, suggesting several sources of infection. Therefore, the
investigators suggested that there was probably a mixture of primary and
reactivated cases. In
addition to the similarity of phage types among TB cases, tuberculin skin
testing results suggested the ongoing transmission of TB in the shelter. For
example, 10 shelter clients who were previously tuberculin negative in May
1985 were re-tested in January 1987 and 3 (30 %) had converted. In addition,
43 clients who were negative in January 1987 were re-tested in June 1987 or
February 1988 and 10 (23 %) had converted. Factors identified as contributing
to the outbreak were the increased number of men with undiagnosed infectious
pulmonary TB, the close proximity of beds in the shelter, and a closed
ventilation system that provided extensive recirculation of unfiltered air. As
a result of the outbreak, a control plan was implemented. This plan included
repetitive mass screening, repetitive skin testing, directly observed therapy,
preventive therapy and modification of the ventilation system to incorporate
UV light disinfection in the ventilation duct work. After the control plan
was in place, five additional individuals with active TB were observed over a
2-year follow-up period. While
the primary focus in this study was on clients of the shelter rather than the
shelter staff, the risk factors present in the shelter before implementation
of the control plan would have also increased the likelihood for transmission
of TB to shelter employees from infectious clients. Thus,
similar to correctional facilities, homeless shelters have a number of risk
factors that facilitate and promote the transmission of TB (e.g., high
incidence of infected residents with an increased likelihood of developing
active disease, crowded living conditions and poor ventilation). Also,
similar to correctional facilities, the evidence in homeless shelters shows
that the failure to promptly identify homeless residents with infectious TB
and the lack of appropriate TB control measures (e.g., lack of
isolation precautions or prompt transfer to facilities with adequate
isolation precautions) resulted in the transmission of TB to shelter
employees. Long-Term Care Facilities for the Elderly Long-term
care facilities for the elderly also represent a high-risk population for the
transmission of TB. TB disease in persons over the age of 65 constitutes a
large proportion of TB in the United States. Many of these individuals were
infected in the past, before the introduction of anti-TB drugs and TB control
programs when the prevalence of TB disease was much greater among the general
population, and have harbored latent infection over their lifetimes. However,
with advancing age, these individuals' immune function starts to decline,
placing them at increased risk of developing active TB disease. In addition,
they may have underlying disease or overall poor health status. Moreover,
residents are often clustered together and group activities are often
encouraged. TB case rates are higher for this age group than for any other. For
example, the CDC reports that in 1987, the 6,150 cases of TB disease reported
for persons ?65 years of age accounted for 27 %
of the U.S. TB morbidity although this group only represented 12 % of the
U.S. population (Ex. 6-14). Because
of the higher prevalence of TB cases among this age group, employees of
facilities that provide long-term care for the elderly are at increased risk
for the transmission of TB. More elderly persons live in nursing homes than
in any other type of residential institution. The CDC's National Center for
Health Statistics reports that elderly persons represent 88 % of the nation's
approximately 1.7 million nursing home residents. As noted by the CDC, the
concentration of such high-risk individuals in long-term care facilities
creates a high-risk situation for the transmission of TB (Ex. 6-14). In
addition to having a higher prevalence of active TB, the recognition of TB in
elderly individuals may be difficult or delayed because of the atypical
radiographic appearance that TB may have in elderly persons (Exs. 7-59, 7-81,
7-82, and 7-83). In this situation, individuals with active TB may go
undiagnosed, providing a source of exposure to residents and staff. While
the increased incidence of TB cases among the elderly in long-term care
facilities may be a result of the activation of latent TB infections, the
transmission of TB infection to residents and staff from infectious cases in
the facilities has been observed and reported in the scientific literature. For
example, Stead et al. (1985) examined the reactivity to the tuberculin skin
test among nursing home residents in Arkansas (Ex. 7-59). This study involved
a cross-sectional survey in which tuberculin skin tests were given to all
current nursing home residents. In addition, all newly-admitted nursing home
residents were skin tested. For the three year period evaluated, 25,637
residents of the 223 nursing homes in Arkansas were tested. Of
12,196 residents who were tested within one month of entry, only 12 percent
were tuberculin positive, including those for whom a booster effect was
detected. However, among the 13,441 residents for whom the first test was
delayed for more than a month, 20.8 % were positive. In addition, the results
of retesting 9,937 persons who were tuberculin negative showed an annual
conversion rate of approximately 5 % in nursing homes in which an infectious
TB case had been recognized in the last three years. In nursing homes with no
recognized cases, the authors reported an annual conversion rate of
approximately 3.5 %. The authors concluded that their data supported the
contention that tuberculosis may be a rather common nosocomial infection in
nursing homes and that new infections with tuberculosis is an important risk
for nursing home residents and staff. Brennen
et al. (Ex.
5-12) described an outbreak of TB that occurred in a chronic care Veteran's
Administration Medical Center in Pittsburgh. This investigation was initiated
as a result of two skin test conversions identified through the employee
testing program. One converter was a nurse working on ward 1B (a locked ward
for neuropsychiatric patients) and the other was a physician working in an
adjacent ward, 1U, who also had significant exposure to ward 1B. The source
of infection in this investigation was traced to two patients who had resided
on ward 1B and who had either a delayed or undiagnosed case of TB. The
contact investigation revealed 8 additional conversions among patients, 4 in
ward 1B and 4 in wards 2B and 4B (units on the floor above 1B). Because
the source cases were initially unidentified, no isolation precautions were
taken. Smoke tracer studies revealed that air discharged from the window air
conditioning unit of one of the source patients discharged directly into the
courtyard. Air from this courtyard was the air intake source for window air
conditioning units in the converters' room on ward 2B and thus was one of the
possible sources of exposure. In
addition to the contact investigation on ward 1B and the adjacent units,
hospital-wide skin testing results were evaluated. Of 395 employees tested,
110 (28 %) were positive. The prevalence in the surrounding community was
estimated to be 8.8 %. Of those employees initially negative, 38 (12 %)
converted to positive status. Included among these were employees in nursing
(18), medical (3), dental (1), maintenance/engineering (3), supply (1),
dietary (9), and clerical (2) services. Occupational
transmission of TB was also reported in a nursing home in Oklahoma (Ex.
6-28). In August 1978, a 68 year old female residing in the east wing of the
home was diagnosed with pulmonary TB. She was subsequently hospitalized. However,
by that time she had already had frequent contact with other residents in the
east wing. As a result, a contact investigation, in which all residents of
the home were given skin tests, was initiated. The
investigation revealed that the reaction rate for residents in the east wing
(34/48, 71 %) was significantly higher than the reaction rates of residents
living in the north and front wings (30/87, 34 %). No baseline skin test
information was presented for the residents to determine the level of
conversion. However, it was noted that half of the nursing home residents
were former residents of a state institution for the developmentally
disabled. A 1970 tuberculin skin test survey of that institution had shown a
low rate of positive reactions. In
addition to the nursing home residents, nursing home employees were also skin
tested. Of the 91 employees tested, 61 (67 %) were negative and 30 (33 %)
were positive. Similar to results observed among the residents, positive
reaction rates were higher for employees who had ever worked in the east wing
(50 %) than for those who had never worked in the east wing (23 %). Retesting
of the employees 3 months later revealed 3 conversions. These results
suggested that there may have been occupational transmission of TB in this
facility. Occupational
transmission has also been observed in a retrospective study of residents and
employees who lived or worked in an Arkansas nursing home between 1972 and
1981 (Ex. 7-83). In this retrospective study, investigators reviewed the skin
testing and medical chart data collected over a 10-year period at an Arkansas
nursing home. Among the nursing home residents who were admitted between 1972
and 1982, 32 of 226 residents (17 %) who were initially tuberculin negative
upon admittance became infected while in the home, based on conversion to
positive after at least two previous negative tests. Twenty-four (63 %) of
these conversions were infected in 1975, following exposure to one infectious
resident. This resident, who had negative skin tests on three previous
occasions during his stay in the home, was not diagnosed with TB until after
he was hospitalized because of fever, loss of weight and productive cough. The
remaining 37 % converted in the absence of a known infectious case. Thus, the
authors suggested that nosocomial infections are likely to result from
persons unsuspected of having TB. Skin
testing was also reviewed for employees of the nursing home. Questionnaires
were completed by 108 full-time employees. Eleven of 68 employees with
follow-up skin tests converted to positive skin status during the study
period. Ten of the 11 (91 %) converters reported that they had been in the
nursing home in 1975, the same year in which many of the residents were also
found to have converted from a single infectious case. In addition, employees
working at least 10 years in the home had a higher percentage of conversions
(9 of 22, 40 %) than employees working less than 10 years (2 of 46, 4.4 %). Based
on the results of this study, the authors concluded that, in addition to
occurrence of TB cases from the reactivation of latent infections among the
elderly, TB can also be transmitted from one resident to another resident or
staff. Consequently, TB must be considered as a potential nosocomial
infection in nursing homes. Thus,
long-term care facilities for the elderly represent a high-risk situation for
the transmission of TB. These types of facilities possess a number of
characteristics that increase the likelihood that active disease may be
present among the facility residents and may go undetected. Similar to other
high-risk settings, the evidence shows that the primary factors in the
transmission of TB among residents and staff have been the failure to
promptly identify residents with infectious TB and initiate and adequately
implement appropriate exposure control measures. Drug Treatment Centers Another
occupational setting that has been identified as a high-risk environment for
the transmission of TB is drug treatment centers. Similar to other high-risk
sites, drug treatment centers have a higher prevalence of TB infection than
the general population. For example, in 1989 the CDC funded 25 state and city
health departments to support tuberculin testing and administration of
preventive therapy in conjunction with HIV counseling and testing. In this
project, 28,586 clients from 114 drug treatment centers were given tuberculin
skin tests. Of those, 2,645 (9.7 %) were positive (Ex. 6-8). When persons
with previously documented positive tests were included, 4167 (13.3 %) were
positive. There
is also evidence to suggest that drug dependence is a risk factor for TB
disease. For example, Reichman et al. (Ex. 7-85) evaluated the prevalence of
TB disease among different drug-dependent populations in New York: (1) An
in-hospital population, (2) a population in a local drug treatment center,
and (3) a city-wide population in methadone clinics. For the in-hospital
population of 1,283 patients discharged with drug dependence, 48 (3.74 %) had
active disease, for a prevalence rate of 3,740 per 100,000. In comparison,
the TB prevalence rate for the total inpatient population was 584 per 100,000
and for New York City as a whole was 86.7 per 100,000. Screening of clients
at a local drug treatment center in Harlem revealed a TB prevalence of 3750
per 100,000 in the drug-dependent population. Similarly, in the New York
methadone program, the city-wide TB prevalence was 1,372 per 100,000. The
authors also reported that although estimates of TB infection rates for both
drug-dependent and non-drug dependent people were similar, the prevalence of
TB disease among the drug-dependent was higher, thus suggesting that drug
dependency may be a risk factor for disease. Clients
of drug treatment centers not only have a high prevalence of TB infection, a
majority of them are intravenous drug users. Of the estimated 645,000 clients
discharged each year from drug treatment centers, approximately 265,000 are
intravenous drug users who either have or are at risk for HIV infection. In
the Northeastern U.S., HIV seroprevalence rates of up to 49 % have been
reported (Ex. 6-8). These individuals are at increased risk of developing
active TB disease. To
determine the risk of active TB associated with HIV infection, Selwyn et
al. (Ex. 5-6) prospectively studied 520 intravenous drug users enrolled
in a methadone maintenance program. In this study, 217 HIV seropositive and
303 seronegative intravenous drug users, who had complete medical records
documenting their history of TB and skin test status, were followed from June
1985 to January 1988. On admission to the methadone program, and at yearly
intervals, all patients were given tuberculin skin tests. Forty-nine
(23 %) of the seropositive patients and 62 (20 %) of the seronegative
patients had positive reactions to the skin test before entry into the study.
Among the patients who initially had negative skin tests, 15 of 131 (11 %)
seropositive patients and 62 of 303 (13 %) seronegative patients converted to
positive tuberculin status. While the prevalence and incidence rates of TB
infection were similar for the two groups of patients, seropositive patients
showed a higher incidence of developing active disease. Active TB developed
in 8 of the seropositive subjects with TB infection (4 %), whereas none of
the seronegative patients with TB infection developed active TB during the
study period. Among
individuals who are infected with HIV or who have AIDS, TB disease may be
difficult to diagnosis because of the atypical radiographic appearance that
TB may present in these individuals. In these individuals, TB may go
undiagnosed and present an unsuspected source of exposure. Clients of drug
treatment centers also may be more likely to discontinue or inadequately
adhere to TB therapy regimens in instances where they develop active disease.
As in other instances, this increases the likelihood of relapse to active
disease or possibly the development of MDR-TB, both of which result in
additional or even prolonged periods of infectiousness during which other
clients or staff can be exposed. There
is evidence showing the transmission of TB in drug treatment facilities among
both the clients and the staff. In a CDC case study (Ex. 5-6), a Michigan man
who was living in a residential substance abuse treatment facility and was
undergoing therapy for a previously diagnosed case of TB disease, was
discovered by the local health department to have MDR-TB. As a result, a
contact investigation was initiated at the drug treatment facility in which
he resided. Of
the 160 clients and staff who were identified as potential contacts, 146 were
tested and given tuberculin skin tests in November. No health screening
program had been in place at the facility. The following March repeat skin
tests were given. Of the 70 persons who were initially tuberculin negative
and were still present in the facility, 15 (21 %) had converted to positive
status (14 clients and 1 staff member). The investigators noted that the
number of converters may have been underestimated for two reasons. Many of
the clients were at risk for HIV infection and thus may have been anergic and
not responded to the tuberculin skin tests. In addition, nearly half of the
clients who were initially negative were not available for repeat skin
testing. Several
factors may have contributed to the observed conversions in this facility. For
example, no health screening program was in place. Therefore, individuals
with TB would go unidentified. In addition, the clients were housed in a
building with crowded dormitories for sleeping. The only ventilation in this
building was provided by opening windows and doors. Thus, environmental
conditions were ideal for the transmission of TB. Consequently,
the high-risk characteristics of clients who frequent these centers (e.g.,
high prevalence of infection and factors increasing the likelihood of
developing active disease) and environmental characteristics of the center (e.g.,
crowding and poor ventilation), lead to drug treatment centers being
considered a high-risk setting for the transmission of TB. The available
evidence shows that the failure to promptly identify clients with infectious
TB and to initiate and properly implement exposure control methods (e.g.,
proper ventilation) resulted in the infection of clients and staff at these
facilities. Conclusion The
available evidence clearly demonstrates that the transmission of TB
represents an occupational hazard in work settings where employees can
reasonably be anticipated to have contact with individuals with infectious TB
or air that may reasonably be anticipated to contain aerosolized M.
tuberculosis as a part of their job duties. Epidemiological studies, case
reports, and outbreak investigations have shown that in various work settings
where there has been an increased likelihood of encountering individuals with
active TB or where high-hazard procedures are performed, employees have
become infected with TB and in some cases developed active disease. While
some infections were a result of more direct and more prolonged exposures,
other infections resulted from non-direct and brief or intermittent
exposures. Because of the variability in the infectiousness of individuals
with active TB, one exposure may be sufficient to initiate infection. Several
factors, common to many of these work settings, were identified as
contributing to the transmission of TB: (1) Failure or delayed recognition of
individuals with active TB within the facility, and (2) failure to initiate
or adequately implement appropriate infection control measures (e.g.,
performance of high-hazard procedures under uncontrolled conditions, lack of
negative pressure ventilation, recirculation of unfiltered air, and lack of
appropriate respiratory protection). Thus, in work settings where employees
can reasonably be anticipated to have contact with individuals with
infectious TB or air that may contain aerosolized M. tuberculosis and
where appropriate infection control programs are not in place, employees are
at increased risk of becoming infected with TB. Infection
with TB is a material impairment of the worker's health. Even though not all
infections progress to active disease, infection marks a significant change
in an individual's health status. Once infected, the individual is infected
for his or her entire life and carries a lifetime risk of developing active
disease, a risk they would not have had they not been infected. In addition,
many individuals with infection undergo preventive therapy to stop the
progression of infection to active disease. Preventive therapy consists of
very toxic drugs that can cause serious adverse health effects and, in some
cases, may be fatal. Although
treatable, active disease is also a serious adverse health effect. Some TB
cases, even though cured, may result in long-term damage to the organ that is
infected. Individuals with active disease may need to be hospitalized while
they are infectious and they must take toxic drugs to stop the progressive
destruction of the infected tissue. These drugs, as noted above, are toxic
and may have serious side effects. Moreover, even with advancements in
treating TB, individuals still die from TB disease. This problem is
compounded by the emergence of multidrug-resistant strains of TB. In these
cases, due to the inability to find adequate drug regimens which can treat
the disease, individuals remain infectious longer, allowing the disease to
progress further and cause more progressive destruction of the infected
tissue. This increases the likelihood of long-term damage and death. V. Preliminary Risk Assessment for Occupational Exposure to
Tuberculosis The
United States Supreme Court, in the "benzene" decision (Industrial
Union Department, AFL-CIO v. American Petroleum Institute, 448
U.S. 607 (1980)), has stated the OSH Act requires that, prior to the issuance
of a new standard, a determination must be made, based on substantial
evidence in the record considered as a whole, that there is a significant
health risk under existing conditions and that issuance of a new standard
will significantly reduce or eliminate that risk. The Court stated that "before
he can promulgate any permanent health or safety standard, the Secretary is
required to make a threshold finding that a place of employment is unsafe in
the sense that significant risks are present and can be eliminated or
lessened by a change in practices" (448 U.S. 642). The
Court in the Cotton Dust case (American Textile Manufacturers Institute
v. Donovan, 452 U.S. 490 (1981)), rejected the use of cost-benefit
analysis in setting OSHA health standards. However, the Court reaffirmed its
previous position in the "benzene" case that a risk assessment is
not only appropriate, but also required to identify significant health risk
in workers and to determine if a proposed standard will achieve a reduction
in that risk. Although the Court did not require OSHA to perform a
quantitative risk assessment in every case, the Court implied, and OSHA as a
matter of policy agrees, that assessments should be put into quantitative
terms to the extent possible. The following paragraphs present an overall
description of OSHA's preliminary quantitative risk assessment for
occupational exposure to tuberculosis (TB). An
earlier version of this risk assessment was reviewed by a group of four
experts in the fields of TB epidemiology and mathematical modeling. The
reviewers were George Comstock, MD, MPH, DPH, Alumni Centennial Professor of
Epidemiology, The Johns Hopkins University; Neil Graham MBBS, MD, MPH,
Associate Professor of Epidemiology, The Johns Hopkins University; Bahjat
Qaqish, MD, PhD, Assistant Professor of Biostatistics, University of North
Carolina; and Patricia M. Simone, MD, Chief, Program Services Branch,
Division of Tuberculosis Elimination, CDC. The reader is referred to the peer
review report in the docket for additional details (Ex. 7-911). The revised
version of OSHA's risk assessment, as published in this proposed rule,
includes OSHA's response to the reviewers' comments as well as updated risk
estimates based on recent purified protein derivative (PPD) skin testing data
made available to the Agency since the peer review was performed and is
generally supported by the reviewers or is consistent with reviewers'
comments. (Note: PPD skin test and tuberculin skin test (TST) are synonymous
terms.) The
CDC estimates that, once infected with M. tuberculosis, an untreated
individual has a 10 % lifetime probability of developing active TB and that
approximately half of those cases will develop within the first or second
year after infection occurs. Individuals with active TB represent a pool from
which the disease may spread. Based on data from the CDC, OSHA estimates that
every index case (i.e., a person with infectious TB) results in at least 2
other infections (Ex. 7-269). For some percentage of active cases, a more
severe clinical course can develop which can be attributed to various factors
such as the presence of MDR-TB, an allergic response to treatment, or the
synergistic effects of other health conditions an individual might have. Further,
OSHA estimates that for 7.78 % of active TB cases, TB is expected to be the
cause of death. Section 6(b)(5) of the OSH Act states that, The
Secretary, in promulgating standards dealing with toxic materials or harmful
physical agents under this subsection, shall set the standard which most
adequately assures, to the extent feasible, on the basis of the best
available evidence, that no employee will suffer material impairment of
health or functional capacity even if such employee has regular exposure to
the hazard dealt with by such standard for the period of his working life. For
this rulemaking, OSHA defines TB infection as a "material impairment of
health", for several reasons. First, once infected with TB, an
individual has a 10 % lifetime likelihood of developing active disease and
approximately 1 % likelihood of developing more serious complications leading
to death. Second, allergic reaction and hepatic toxicity due to
chemoprophylaxis with isoniazid, which is one of the drugs used in the
recommended course of preventive treatment, pose a serious threat to a large
number of workers. Third, defining infection with M. tuberculosis as
material impairment of health is consistent with OSHA's position in the
Bloodborne Pathogens standard and is supported by CDC and several
stakeholders who participated in the pre-proposal meetings, as well as Dr.
Neil Graham, one of the peer reviewers of this risk assessment. In his
comments to OSHA, Dr. Graham stated, The
focus of OSHA on risk of TB infection rather than TB disease is appropriate. TB
infection is a potentially adverse event, particularly if exposure is from a
MDR-TB patient, or if the health-care or institutional worker is HIV
seropositive. In addition, a skin test conversion will in most cases mandate
use of chemoprophylaxis for > 6 months which is at least inconvenient and
at worst may involve adverse drug reactions. (Ex. 7-271) The
approach taken in this risk assessment is similar to the approach OSHA took
in its risk assessment for the Bloodborne Pathogens standard. As with
bloodborne pathogens, the health response (i.e., infection) associated with
exposure to the pathogenic agent does not depend on a cumulative level of
exposure; instead, it is a function of intensity and frequency of each
exposure incident. However, unlike hepatitis B, where the likelihood of
infection once an exposure incident occurs is known with some degree of
certainty, the likelihood of becoming infected with TB after an exposure
incident is not as well characterized. With TB, the likelihood of infection
depends on the potency of an exposure incident and the susceptibility of the
exposed individual (which is a function of the person's natural resistance to
TB and his or her health status). Further, the potency of a given exposure
incident is highly dependent on several factors, such as the concentration of
droplet nuclei in the air, the duration of exposure, and the virulence of the
pathogen (e.g., pulmonary and laryngeal TB are considered more
infectious than other types). The
Agency has sufficient data to quantify the risk associated with occupational
exposure to TB among <<health care workers>> in hospitals on a state-by-state
basis. In addition to hospital employee data, OSHA has obtained data on
selected health care employee groups from the TB Control Office of the
Washington State Health Department. These groups include workers employed in
long-term health care, home health care, and home care. Small entities are
encouraged to comment and submit any data or studies on TB infection rates
relevant to their business. Because
it is exposure to aerosolized M. tuberculosis that places workers at
risk of infection, and not some factor unique to the health care profession,
the Agency concluded that the experience of these groups of <<health care
workers>>
is representative of that of the other "high-risk" workers covered
by this proposal. This means that the risk estimates calculated for these
groups of workers are appropriate to use as the basis for describing the
potential range of risks for workers in other work settings where workers can
be expected to come into close and frequent contact with individuals with
infectious TB (or with other sources of aerosolized M. tuberculosis)
as an integral part of their job duties. As discussed in section IV (Health
Effects), epidemiological studies, case reports, and outbreak investigations
have shown that workers in various work settings, including but not limited
to hospitals, have become infected with tuberculosis as a result of
occupational exposure to aerosolized M. tuberculosis when appropriate
infection control programs for tuberculosis were not in place. In
this preliminary risk assessment, OSHA presents risk estimates for TB
infections, cases of active disease, and TB-related deaths (i.e., where TB is
considered the cause or a major contributing cause of death) for workers with
occupational exposure to tuberculosis. A
number of epidemiological studies demonstrate an increased risk of TB
infection among <<health care workers>> in hospitals and other work settings. A
brief review of a selection of these studies is presented below, followed by
OSHA's estimates of excess risk due to occupational exposure. Finally, OSHA
presents a qualitative assessment of the risk of TB infection caused by
occupational exposure to tuberculosis in correctional facilities, homeless
shelters, drug treatment centers, medical laboratories, and other high-risk
work groups. Review of the Epidemiology of TB Infection in Exposed Workers There
are several studies in the published scientific literature demonstrating the
occupational transmission of infectious TB. Reports of TB outbreaks and
epidemiologic surveillance studies have shown that health care and certain
other workers are, as a result of their job duties, at significantly higher
risk of becoming infected than the average person. OSHA
conducted a thorough search of the published literature and reviewed all
studies addressing occupational exposure to tuberculosis and TB infection in
hospitals and other work settings. All published studies show positive
results (i.e., workers exposed to infectious individuals have a high
likelihood of becoming infected with TB). Because there are so many studies,
OSHA selected a representative subset of the more recent studies conducted in
the U.S. to include in this section. These studies were chosen because they
show occupational exposure in various work settings, under various working
conditions, and under various scientific study designs. OSHA's
summary of the studies is presented in Table V-1(a) and Table V-1(b). These
studies represent a wide range of occupational settings in hospitals, ranging
from TB and HIV wards in high prevalence areas, such as New York City and
Miami, to hospitals with no known TB patients located in low prevalence areas
such as the state of Washington. The studies include prospective studies of
entire hospitals or groups of hospitals, retrospective surveys of
well-controlled clinical environments, such as an HIV ward in a hospital, and
case studies of single-source infection (i.e., outbreak investigations). Outbreak
investigations describe occupational exposure to tuberculosis from single
index patients or a well-defined group of patients. Such investigations are
more likely to demonstrate an upper limit of occupational risk in different
settings, usually under conditions of suboptimal environmental and infection
controls. Although outbreak investigations demonstrate the existence of
occupational risk under certain conditions and the importance of the early
identification of suspect TB patients quite well, these studies do not
provide information conducive to risk assessment estimations. Limitations of
outbreak investigations include the frequent absence of baseline PPD test
results, the difficulty of extrapolating the results to non-outbreak
conditions of TB exposure, and, often, small sample sizes. Table V-1(a) lists
some of the published outbreak investigations and shows the risks posed to <<health care
workers>>
by such outbreaks, as well as the failures in control programs contributing
to these episodes. Prospective
and/or retrospective surveillance studies are used to estimate conversion
rates from negative to positive in PPD skin testing programs. These
conversion rates can be used to estimate the excess incidence of TB
infection. Surveillance studies among <<health care workers>> lend themselves to a more
systematic evaluation of the risk of TB infection than outbreak
investigations, for several reasons. First, these studies better reflect the
risk of TB experienced by workers under routine conditions of exposure. Second,
these studies are usually based on a larger group of workers and therefore
yield more precise and accurate estimates of the actual risk of infection. However,
the extent to which results from surveillance studies can be generalized
depends on a careful evaluation of the study population. Some studies report
skin test conversion rates for all workers in the hospital(s) under study. Such
studies often include large groups of employees with little or no exposure to
TB. Results from such studies may reflect an overall estimate of risk in that
environment, but may underestimate the occupational risk of those with
frequent exposure. Other
surveillance studies report PPD conversion rates of more narrowly-defined
groups of workers, usually those working in "high-risk" areas
within a hospital such as the HIV or TB wards. Some of these studies have
internal control groups (i.e., they compare PPD conversion rates between a
group of workers with extensive exposure to TB and a group of workers with
minimal or no exposure to TB), thus making it possible to more precisely
quantify the magnitude of excess risk due to occupational exposure. However,
these studies are also limited in their usefulness for risk assessment
purposes. They usually have small sample sizes, making it more difficult to
observe statistically significant differences. More importantly, internal
control groups may overestimate background risk, and thus underestimate
excess occupational risk, unless painstaking efforts are made to eliminate
from the control group those individuals with the potential for occupational
exposure, a difficult task in some hospital environments. Table V-1(b)
contains a selected list of published surveillance studies. In
reviewing Table V-1(a) and Table V-1(b), the reader should bear in mind that
these tables are not intended to present an exhaustive list of epidemiologic
studies with TB conversion rates in occupational settings. Instead, these
tables present brief summaries of some of the epidemiologic evidence of
occupational TB transmission found in the published literature; they are
intended to convey the seriousness of the risk posed to <<health care
workers>>
and to illustrate how failures in control programs contribute to this risk. Upon
reviewing these studies, a consistent pattern emerges: these work settings
are associated with a high likelihood for occupational exposure to
tuberculosis, and high rates of TB infection are being observed among <<health care
workers>>. Quantitative Assessment of Risk Data
availability usually dictates the direction and analytical approach OSHA's
risk assessment can take. For this rulemaking, three health endpoints will be
used: (1) TB infection, which is ``material impairment of health'' for this
proposed standard; (2) Active disease following infection; and, (3) Risk of
death from active TB. In
order to account for regional variability in TB prevalence and therefore to
account for expected variability in the risk of TB infection in different
areas, the Agency chose to develop occupational risk estimates on a
state-by-state basis. This approach was criticized by Dr. Neil Graham as
being too broad and "* * * insufficient in light of the tremendous
variability * * * that can occur within a state." (Ex. 7-911). The
Agency recognizes that risk estimates on a county-by-county basis would be
preferable; however, the unavailability of comprehensive county data has
prevented the Agency from conducting such analysis. The
annual excess risk of TB infection due to occupational exposure is defined as
a multiplicative function of the background rate of infection and is
expressed as: where: p
is the annual excess risk due to occupational exposure, Estimates
of ERRo are derived from surveillance studies of workers with
occupational exposure to TB. ERRo is defined as the relative
difference between the overall exposed worker risk and the background
(population) risk and is calculated as the difference between overall worker
and background risk divided by the background risk. The
annual excess risk due to occupational exposure is defined as a function of
the background risk because of data limitations. If data on overall worker
risk were available for each state, then the excess risk due to occupational
exposure would simply be the difference between overall worker risk and
background risk. Instead, the annual excess risk due to occupational exposure
(i.e., p) is estimated using a multiplicative model because data on overall
worker risk (i.e., Rw) were available only for the states of
Washington, and North Carolina and for Jackson Memorial Hospital located in
Miami, Florida. Therefore, the annual excess risk due to occupational
exposure in state i (pi) is expressed as: where: Rwj
is the overall worker risk estimated from surveillance studies (study j), Rbj
is the study control group risk (i.e., study background risk), and Rbi
is the background rate for state i. When
i=j (i.e., Washington State or North Carolina), the excess risk due to
occupational exposure, is expressed as the straight difference between
overall worker risk and background risk. OSHA
calculated estimates of ERRo based on three occupational studies:
the Washington State study, the North Carolina study, and the Jackson
Memorial Hospital study (Exs. 7-263, 7-7, 7-108). These estimates were
expressed as percent change above each study's background. The derivation of
these estimates is described in section 2. In
order to estimate an overall range of occupational risk of TB infection,
taking into account regional differences in TB prevalence in the U.S., OSHA:
(1) Estimated background TB infection rates by state (Rbi), and
(2) applied estimates of ERRo, derived from the occupational
studies, to the state background rates to calculate estimates of excess risk
due to occupational exposure by state. OSHA
used a multiplicative function of each state's background infection rate to
estimate excess risk of TB infection because the probability of occupational
infection can be viewed as a function of the number of contacts and frequency
of contacts with infectious individuals. Thus, estimates of expected relative
increase in risk above background due to occupational exposure are calculated
for the three available studies and these relative increases (i.e. ERRo)
are multiplied by background rates for each state to derive estimates of
excess occupational risk by state. These state estimates are then used to
derive a national estimate of occupational risk. The
CDC compiles and publishes national statistics on the incidence of active TB
in the U.S. by state based on reported cases. OSHA relied on these data to
estimate TB infection background rates through the use of a mathematical
model because information on TB infection is not being collected nationwide
by CDC. A more detailed discussion on the methodology and derivation of
background risk estimates by state is found in section 3, and discussion on
the estimation of occupational risk estimates by state is found in section 4
of this risk assessment. Because
section 6(b)(5) of the OSH Act requires OSHA to assess lifetime risks, OSHA
has converted the annual excess risk due to occupational exposure into an
excess lifetime risk based on a 45-year working lifetime. The formula used to
calculate lifetime occupational risk estimates of the probability of at least
one occurrence of TB infection due to occupational exposure in 45 years is
expressed as { 1-(1-p)45 }, where p is the annual excess risk due
to occupational exposure. Two assumptions are critical in defining lifetime
risk: (1) the exposure period is 45 years, and (2) the annual excess risk
remains constant. The implication of the second assumption is that the
worker's exposure profile and working conditions, which may affect the level
and intensity of exposure, and the virulence of the pathogen, remain
unchanged throughout a working lifetime. The merit of this assumption was
questioned by Dr. Graham, because, as he states "* * * patient contact
may vary greatly throughout a career for many HCWs [<<health care workers>>]." and " * * *
physicians (and nurses) often do not have extensive patient contact until
[their] mid-twenties, while other workers increasingly retire early." Dr.
Graham recommends that OSHA's risk assessment be adjusted to account for
variable exposure levels and variable working lifetimes. Although accounting
for variable exposure levels could result in more precise risk estimates, the
unavailability of comprehensive information on lifetime TB exposure scenarios
by occupational group prevented the Agency from developing a more complex
risk model. OSHA
has customarily assumed a 45 year working lifetime in setting health
standards. The Agency believes that this assumption is reasonable and
consistent with the Act. The Act requires the Secretary to set a standard for
toxic substances that would assure "no employee * * * suffer material
impairment of health or functional capacity even if such employee has
regular exposures to the hazard for the period of his working lifetime."
29 U.S.C. § 655(b)(5) (emphasis added). The U.S. Court of Appeals for the
District of Columbia upheld the use of a 45-year lifetime in the asbestos
standard against an assertion by the Asbestos Information Association that
the average duration of employment was five years. Building and
Construction Trades Department, AFL-CIO v. Brock, 838 F.2d 1258,
1264, 1265 (D.C. Cir. 1988). The Court said that OSHA's assumption
"appears to conform to the intent of Congress" as the standard must
protect even the rare employee who would have 45 years of exposure. Id. at
1264. In addition, while working lifetimes will vary, risk is significant for
some who work as little as one year and, at any rate, individual and
population risks are likely to remain the same so long as employees who leave
one job are replaced by others, and those who change jobs remain within a
covered sector. Nevertheless, the Agency solicits information regarding the
likelihood of exposure to active TB in the workplace and duration of
employment in various occupational groups. Lifetime risk estimates of TB
infection by state are described in section 4. Lifetime
risk estimates of developing active TB are calculated from lifetime risk
estimates of TB infection assuming that, once infected, there is a 10 %
likelihood of progressing to active TB. These estimates are discussed in
section 4. Further, the number of deaths caused by TB is calculated from the
lifetime estimates of active TB using OSHA's estimate of TB case fatality
rate, also discussed in section 4. 1.
Definitions For
the purpose of estimating incidence rates, TB infection rate is
defined as the annual probability of an individual converting from negative
to positive in the tuberculin skin test. Annual occupational risk is
defined as the annual excess risk of becoming infected with TB due to
occupational exposure, and is estimated as a function of the background risk.
Lifetime occupational risk is defined as the excess probability of
becoming infected with TB due to exposure in the workplace, at least once, in
the course of a 45-year working lifetime and is estimated as { 1-(1-p)45
} where p is the annual occupational risk of TB infection. 2.
Data Sources for Estimating Occupational Risk The
quantitative data needed to develop an overall national estimate of risk for
TB infection due to occupational exposure are not available. The CDC does not
publish occupational data associated with TB infection incidence and active
TB on a nationwide basis. There has been some effort to include occupational
information on the TB reporting forms, but only a limited number of states
are currently using the new forms that capture occupational information in a
systematic way. However,
there are a number of sources that permit the risk in occupational settings
to be reasonably estimated and, with the aid of mathematical models, to
develop estimates of excess relative occupational risk (ERRo),
which can then be multiplied by the state-specific background rates to yield
estimates of excess occupational risk. OSHA has identified three data sources
that are suitable for assessing the excess risk of TB infection in <<health care
workers>>
with occupational exposure. These include: (1) A 1994 survey of tuberculin
skin testing in all health care facilities in Washington State; (2) A
state-wide survey of hospitals in North Carolina, conducted in 1984-1985,
which addressed TB skin testing practices, TB infection prevalence, and TB
infection incidence among hospital employees in that state; and (3) the
employee tuberculin skin test conversion database from Jackson Memorial
Hospital in Miami, Florida. In addition to these hospital employee data, the
Agency has obtained data on selected other work groups from the state of
Washington. These groups include workers employed in long-term health care,
home health care, and home care. On
the issue of data availability for this risk assessment, Dr. Graham agrees
with OSHA that there are no comprehensive data available with respect to
occupational risk of TB infection in health care and other institutions in
the U.S. Instead of relying on two state specific studies, Dr. Graham
recommends, though with serious reservations, the use of a review study by
Menzies et al. (Ex. 7-130). Dr. Graham admits that the "validity of the
estimates in these reports [reviewed in the Menzies et al. study] must be open
to serious question * * *" for the following reasons, which were pointed
out by Dr. Graham: several of the studies reviewed are very old and not
relevant to TB risk in the 1990s; four studies use tine tests and
self-reports of skin test results, which are not useful for estimation of
risk of TB infection; the studies were not consistent in the inclusion of
high and low risk workers; two-step testing was not done; and the
participation rates were extremely low or unreported in many of the studies
included in this review. OSHA
has chosen not to rely on the Menzies et al. review study, because, in
addition to Dr. Graham's reservations (which the Agency shares), OSHA is also
concerned about the inclusion in the Menzies et al. review article of studies
conducted outside the U.S. Factors known to affect the epidemiology of TB,
such as environmental conditions, socio-economic status, and work practices,
are expected to differ greatly from one country to another, and are not
controlled for in the statistical analyses of these studies. For all of these
reasons, the Agency has chosen to rely solely on U.S. studies for its
quantitative risk estimations. Estimates
of excess risk due to occupational exposure are expressed as the percent
increase above background based on relative risk estimates derived from
occupational studies. Internal control groups provided estimates of
background risk for the Washington state and Jackson Memorial data sets. In
the absence of a suitable internal control group, the estimated annual state-wide
TB infection rate, as calculated in Section 3, was used as the background
rate in the North Carolina study. (a)
Washington State Data: Initially, OSHA relied on a three-year
prospective study, conducted between 1982 and 1984 in the state of Washington,
to derive an estimate of excess risk for TB infection as a result of
occupational exposure (Ex. 7-42). OSHA received several objections to the use
of this study. The study used hospitals with no known TB cases as
"controls" based on the assumption that in those hospitals the risk
of TB infection to employees may be the same as for the general population. Dr.
Qaqish noted that this assumption is highly questionable and that the use of
such controls is not appropriate. Dr. Graham and Dr. Qaqish pointed out that
the published results did not include conversions identified through contact
investigations, which means that the conversion rate reported in that study
was likely to be an underestimate of the true risk. In addition, the
commenters noted that the study was designed to estimate the effectiveness of
the TB screening program and may have produced skin testing results biased
toward the null; the study is relatively old; and, the study was conducted
prior to the AIDS epidemic and therefore the results may not be relevant to
the occupational risk at present because the relationship between HIV and TB
is not reflected in this study. In
an effort to respond to reviewers' comments, the Agency chose to update the
analysis by relying on a data set of tuberculin skin testing results from a
survey of the state's tuberculin skin testing program in 1994. This survey is
conducted by the TB Control Office in the Washington State Health Department
and it covers all hospitals in the state, as well as long-term care, home
health care, and home care facilities. OSHA was given access to the database
for the 1994 survey as well as data on conversions identified through contact
investigations for the same year (Ex. 7-263). Table V-2 summarizes the
results of the 1994 survey. Of the 335 health care establishments in the
state of Washington, 273 responded to the survey, for an overall response
rate of 81.5 %. Of those, 76 were hospitals, 142 were long-term care, 47 were
home health care, and 8 were home care facilities. Hospitals had the highest
survey response rate (85 %) and home health care had the lowest (77 %). Every
employee at risk for TB infection (i.e., who was known to be tuberculin skin
test negative at the start of the study period) in the participating
hospitals and long-term care facilities was given a tuberculin skin test,
including administrators, housekeepers, business office staff, and all
part-time employees. Testing in home health care facilities was generally
confined to those nursing staff who had direct client contact. Employees in
home care are those who provide services to patients in home health care and
include food handlers, cleaning aides, personal care-givers, and some social
workers. The
overall rate of skin test conversion for workers in the health care system in
Washington State in 1994 was 3.24 per 1,000 employees tested. This is greater
than a 4-fold increase from the estimated state-wide background rate of 0.69
per 1,000 at risk, as calculated in section 3. The annual rate of TB
conversion ranged from 1.27 per 1,000 tested for hospital employees to 9.80
per 1,000 tested for long-term care employees. The
annual rate of 9.8 per 1,000 for long-term care employees probably reflects
the high potential for exposure to undiagnosed active TB in those facilities.
As a rule, long-term facilities in Washington State do not have AFB isolation
rooms. Therefore, residents with no obvious TB symptoms but who might be
infectious spend most of their time in open spaces exposing other residents
and workers to infectious droplet nuclei. However, once a resident has been
identified as a suspect TB patient, that person is transferred to a hospital
until medically determined to be non-infectious. Also,
since employees who were 35 years of age or younger were not given a two-step
test at hiring, and a high percentage of employees are foreign born and
therefore most likely to have been vaccinated during childhood with the BCG
vaccine, some of the conversions observed might be late boosting because of
BCG. However, an almost two-fold increase in risk for long-term care workers
even as compared to the significant excess risk among home <<health care
workers>>
clearly indicates that the risk of TB infection for workers in long-term care
is high and not likely to be fully explained by late boosting. Beginning in
1995, two-step testing has been done on all new hires in Washington State. Thus,
tuberculin skin testing data for 1995 are not expected to be influenced by
possible late boosting; OSHA will place the 1995 data in the rulemaking
record as they become available. Hospital
workers had the lowest overall rate of conversion (overall rate of 1.27 per
1,000). This, in part, can be attributed to the existence of extensive TB
control measures in that environment in Washington State. Compliance with the
CDC Guidelines and OSHA's TB Compliance Directive is quite high in Washington
State because: (a) There is a strong emphasis on early identification of
suspect TB patients; (b) there is a strong emphasis on employee training and
regular tuberculin skin testing (although on a less-frequent basis than
recommended in the Guidelines: All employees are tested at hire and annually
thereafter); (c) the use of respirators is expected when entering an
isolation room; and (d) all isolation rooms are under negative pressure, have
UV lights, and exhaust to the outside. In addition, conversion data in
hospitals are more likely to represent true TB infections than in the other
health care settings, because hospitals are more likely to re-test converters
in an effort to eliminate false-positive cases. A
more thorough analysis of the hospital data is presented in table V-3. Because
the Washington State survey was not designed to compare exposed persons with
matched controls who have had no exposure, several alternative definitions of
an internal control (unexposed) group were used in analyzing this data set. Three
different analyses, shown in table V-3, produced estimates of annual
occupational infection rates ranging from 0.4 to 0.6 per 1,000 above control
(i.e., ranging from a 47 % to an 84 % increase above control). In order to
minimize the likelihood of contaminating the control group with persons
having significant occupational exposure, OSHA defined the control group as
workers in hospitals located in zero-TB counties and with no known TB
patients. This analysis is summarized in table V-3 as Definition 1. If
potential for occupational exposure is defined as either working in a
hospital in a county that has active TB or in a hospital that has had TB
patients, then the annual risk due to occupational exposure is 47 % above
background. The excess annual risk due to occupational exposure appears to be
approximately 60 % above background, if workers in hospitals with a
transfer-out policy for TB patients are considered to be the control group,
shown as Definition 2 in table V-3. A 60 % increase above background is not
statistically significantly different from a 47 % increase and therefore
these two "control" groups can be viewed as producing
"statistically" equivalent results. However, the Agency believes
that Definition 1 is more appropriate, though the risk estimates are higher
if the control group is defined based on Definition 2, because there is a
higher likelihood of potential for exposure to a patient with undiagnosed TB
under Definition 2 conditions. Comparisons of all hospital TST data to the
state-wide estimate of TB infection rate resulted in an estimate of the
annual excess occupational risk of approximately 84 % above background, shown
in table V-3 as Definition 3. Estimates of the annual and lifetime
occupational risk of TB infection for the average health care worker in
hospitals by state, extrapolated from this study and using Definition 1 as
the control group, are presented and summarized in section 4. Annual
rates of excess risk due to occupational exposure were estimated for
long-term care, home health care, and home care and are presented in Section
4. The same control group used in the hospital data analysis, Definition 1
(i.e., 0.876/1,000 workers at risk) was used to estimate the background risk
among workers in long-term care, health care, and home care facilities and
settings. Using 0.876 as the background infection rate for workers in these
settings (a) provided a level of consistency among the Washington data
analyses, and (b) resulted in a lower estimate of occupational risk for the
non-hospital health care workplaces than would have resulted had the
state-wide background risk estimate (i.e., 0.67/1,000 see Section 3) been
used. When industry-specific risk data are used, there is approximately a
10-fold increase in annual risk for workers in long-term care, a 5-fold
increase in annual risk for workers in home health care, and a 1-fold
increase in annual risk for workers in home care (see Section 4). Estimates
of the range of annual and lifetime occupational risk for the average health
care worker in long-term care, home health care, and home care by state,
extrapolated from the Washington State study, are presented in Section 4. (b)
North Carolina Study: A state-wide survey of all hospitals in North
Carolina (NC) was conducted in 1984-1985 (Ex. 7-7). The survey's
questionnaire was designed to address three main areas of concern affecting
hospital employees: (1) Tuberculin skin testing practices; (2) TB infection
prevalence; and (3) TB infection incidence. The incidence of new infections
among hospital personnel was assessed over a five-year period by reviewing
tuberculin skin test conversion data during calendar years 1980 through 1984
and was calculated as the number of TB skin test conversions divided by the
number of skin tests administered. (Since most employees were only given
annual testing, the number of tests administered is a very close estimate of
the total number of people tested within a year and thus can be used as the
denominator in estimating infection incidence.) Only 56 out of 167 hospitals
reported information on TB conversion rates (34 % response rate). The authors
estimated a state-wide TB infection rate of 11.9 per 1,000 per year for
hospital employees in 1984 and a five-year mean annual infection rate of 11.4
per 1,000, with a range of 0-89 per 1000 employees at risk for TB infection. An
analysis of the data by region (i.e., eastern, central, western) showed that
the eastern region had consistently higher rates (with an average infection
rate of 18.0 per 1,000) followed by the central region (7.0 per 1,000) and
the western region (6.1 per 1000). Results of this study are shown in table
V-4. Use
of this study's overall results for risk estimates was criticized by the peer
reviewers because of design flaws in the study (e.g., high
non-response rate, inconsistent skin testing practices, and limited two-step
testing) and, most importantly, the presence of atypical mycobacteria
(contributing to false positive results) in the eastern part of the state. Based
on further input from Dr. Comstock, the Agency chose to rely on the study
results from the western region only, because they are considered to be more
representative of the "true" risk of infection and are expected to
be less confounded by cross-reactions to atypical mycobacteria. Further, the
Agency chose to rely on the conversion rate estimated for 1984 because it was
the most recent data reported in the study. Therefore, the western region
conversion rate of 7.2 per 1,000, estimated based on responses to the survey
from eight hospitals in 1984, was used as an overall worker conversion rate. Further,
the 1984 rate was adjusted by the percent decrease of active TB between 1984
and 1994 in North Carolina so that the final worker conversion rate for 1994
based on the western region rates reported in this study was estimated to be
5.98 (7.2 * 532/641 = 5.98) per 1,000 employees at risk for TB infection. The
North Carolina study did not have an internal control group to use as the
basis for estimating excess risk due to occupational exposure because the
conversion rates presented in this study were based on TST results for the
entire hospital employee population. In the absence of an internal control
group, the Agency used the estimated state-wide background rate of 1.20 per
1,000 as the background rate of infection for the western region in North
Carolina (see Section 3) to estimate excess risk due to occupational
exposure.(1) Based on this study, annual
occupational risk is approximately four times greater than background
[(5.98-1.2)/1.2 = 3.98]. Estimates of the annual and lifetime occupational
risk of TB infection based on this study by state are presented in Section 4. (c)
Jackson Memorial Hospital Study: Jackson Memorial Hospital (JMH) is a
1500-bed general facility located in Miami, Florida, employing more than
8,000 employees. It is considered one of the busiest hospitals in the U.S. It
is the primary public hospital for Dade County and the main teaching hospital
for the University of Miami School of Medicine. JMH treats most of the TB and
HIV cases in Dade County and, consequently, there is a higher likelihood of
occupational exposure to TB in this facility than in the average hospital in
the U.S. From March 1988 to September 1990, an outbreak of
multidrug-resistant TB (MDR-TB) occurred among patients and an increased
number of TST conversions was observed among <<health care workers>> on the HIV ward. This prompted a
re-evaluation of the hospital's infection control practices and the
installation of engineering controls to minimize exposure to TB. As part of
the evaluation of the outbreak, NIOSH did a Health Hazard Evaluation and
issued a report (Ex. 7-108). In addition, NIOSH conducted a retrospective
cohort study of JMH to determine whether the risk of TB infection was
significantly greater for <<health care workers>> who work on wards having patients
with infectious TB than those who work on wards without TB patients. For
the data analysis of this study, "potential for occupational
exposure" was defined based on whether an employee worked on a ward that
had records of 15 or more positive cultures for pulmonary or laryngeal TB
during 1988-1989. In other words, positive culture was taken as a surrogate
for exposure to infectious TB. The authors restricted the "exposed"
group to employees on wards with exposures to pulmonary or laryngeal TB
because they intended to restrict the study to hospital workers with exposure
to patients with the highest potential for being infectious. There were 37
wards at JMH that had submitted at least one positive culture during
1988-1989. Seven wards met the criteria of 15 or more and were therefore
included in the "exposed" group. These were the medical intensive
care unit, five medical wards, and the emergency room. The
"control" group was defined as hospital workers assigned to wards
with no TB patients (i.e., wards with no records of positive cultures during
1988-89). The "control" wards were post-partum, labor and delivery,
newborn intensive care unit, newborn intermediate care unit, and well newborn
unit. The results of this analysis are presented in Table V-5. Table
V-5 shows a substantially elevated risk for those workers with potential
exposure to patients with infectious TB. The relative risk ranges from 9 to
11.7 between 1989 and 1991 and is statistically significant for all of those
years. This suggests that the excess risk due to occupational exposure is
approximately 8-fold above background; this is an overall risk estimate that
reflects the occupational risk of TB infection for JMH employees with patient
contact, because this analysis included everyone tested in the
"exposed" and "control" group, regardless of his or her
specific job duties or length of patient contact. An
analysis of various occupational groups within this cohort showed that nurses
and ward clerks in the "exposed" groups had the highest conversion
rates: 182 and 156 conversions per 1,000 workers tested, respectively. Other
studies have shown that <<health care workers>> who provide direct patient care
are at greater risk for infection than workers who do not provide direct
patient care. The high risk seen in ward clerks was unexpected since these
workers are not involved in direct patient care. However, in the emergency
room, the risk for TST conversion for the ward clerks was almost three times
higher than for the nurses, 222 and 83 per 1,000, respectively. Ward clerks
in the emergency room are responsible for clerical processing of patients
after triage, handling specimens for the laboratory, and gathering clothing
and valuables from admitted patients. During these interactions, there may
have been less strict adherence to infection control measures, and this could
explain the high conversion rate. OSHA
used the results from the 1991 analysis of the data in the JMH study to
estimate occupational risk of TB infection in hospital workers with a
relatively high likelihood of occupational exposure, for the following
reasons: (a) 1991 represents the most recent year for which conversion data
are available prior to the time when TB infection control measures were fully
implemented at JMH; and (b) The higher conversion rates reported for 1990 and
1989 (75.5 and 62.2 per 1,000 respectively) may be atypical, i.e., they may
to some extent reflect the effect of the outbreak and not the long-term
occupational risk. Based
on the results of this study, OSHA estimates that the annual excess risk of
TB infection due to occupational exposure is 7.95 times greater than
background. Estimates of annual and lifetime occupational risk of TB
infection for the average health care worker in hospitals by state,
extrapolated from this study, are presented and summarized in section 4. 3.
Estimation of Background Risk of TB Infection OSHA's
methodology for estimating population (background) TB infection rates relies
on the assumption that TB infection occurring in an area can be expressed as
a numerical function of active TB cases reported in the same area. If the
likelihood of observing any infection in a population is minimal, then the
likelihood of observing active disease diminishes. Conversely, the presence
of active TB implies the presence of infection, since active disease can only
progress from infection. Therefore, there is a functional relationship
linking TB infections to active disease being observed in a particular area
during a specified time period. Peer
reviewer comments on this assumption varied. Neil Graham states in his
comment "Although factors such as migration and distribution of the
population may influence this relationship it seems probable that this
assumption is largely correct and justifiable." (Ex. 7-271). On the
other hand, Dr. Simone expresses concern over this assumption and states
"It is not necessarily true that a change in cases now reflects the risk
of infection now." Dr. Qaqish demonstrates in his comment that the net
effect of assuming a proportional relationship between the number of active
cases and the number of new infections is to introduce a possible bias into
the estimate of background risk of TB infection, although such a bias could
work in either direction, i.e., toward increasing or decreasing the estimate
of risk. Dr. Qaqish further states that in the absence of more "relevant
data," it is not possible to determine the actual net effect in
magnitude and direction of the bias and "without obtaining additional
data, it would be impossible for the Agency to improve on the accuracy of the
risk estimates * * * " OSHA has considered all of the reviewer comments
and is aware of the inherent uncertainty and the potential for bias
associated with the use of this assumption; however, in the absence of the
additional "relevant" data to which Dr. Qaqish refers, the Agency
believes this approach to be justifiable. In
defining the model used to estimate the annual infection rates occurring in a
geographical area based on data on active disease cases reported for the same
area, infections progressing to active disease are assigned to one of three
distinct groups: those occurring this year, last year, and in previous years. TB
cases reported to CDC each year are a combination of new and old infections
that have, for various reasons, progressed to active disease. Until recently,
it was believed that most of the active cases were the product of old
infections. However, with the use of DNA fingerprinting techniques,
researchers have reported that a larger percentage of active cases may be
attributed to new or recent infections. Small et al. reported, in an article
on tracing TB through DNA fingerprinting, that as many as 30 % of the active
cases reviewed in the study may be the result of recent infections (Ex.
7-196). In
this risk assessment, the Agency assumes the lifetime risk that an infection
will progress to active TB to be approximately 10 %. This estimate is
supported by CDC and in her comment, Dr. Simone states that: "The
assumption * * * is generally agreed upon." Dr. Comstock and Dr. Qaqish
both questioned the validity and accuracy of CDC's estimate. Their comments
suggest that the true lifetime rate of progression from infection to active
disease for adults may be less than 10 percent. However, as Dr. Graham points
out, the 10 % assumption is a widely accepted "rule of thumb" and
is also in relative agreement with data from the unvaccinated control group
of the British Medical Research Council (MRC) vaccination trial in adolescents
(Ex. 7-266). In
the MRC study, 1,338 adolescents' skin tests converted following TB exposure
where the precise date of conversion was known. Of these, 108 (8.1 %)
individuals developed active TB during follow-up. Of these, 54 % developed
active TB within one year and 78 % within 2 years. This results in a risk of
approximately 4 % at one year, 6 % at two years, and an overall risk of 8 %. Given
that the risk of TB reactivation increases with age, the lifetime risk is
expected to be higher than the 8 % attained in this study and, as Dr. Graham
points out, a 10 % overall lifetime risk seems reasonable. Based
on Dr. Graham's recommendation to rely on the progression rates from the MRC
study, OSHA changed the assumption on the progression parameters from 2.5 %
(first year), 2.5 % (second year), and 5 % (remaining lifetime) to 4 %, 2 %
and 4 %, respectively. Therefore the total 10 % progression from infection to
active disease is partitioned into 3 groups: progression during the first
year after infection (40 % of all infections that eventually progress, for a
net probability of 4 %), progression during the second year (20 % of all
infections that eventually progress, for a net probability of 2 %), and
progression during all subsequent years (the remaining 40 % of progressing
infections). This last probability (4 %) is assumed to be uniformly
distributed across the remaining lifespan. TB
rates vary considerably by geographic area, socio-economic status, and other
factors. In an attempt to account for some of those factors, to the extent
possible, background TB infection rates have been estimated separately for
each state. The derivation of background infection rates involves several
steps for which the process and formulae are presented below. Step 1:
Background rate of TB infection for state i in year j is defined as: where: Bi(j)
is the background TB infection rate for state i in year j Ii(j)
is an estimate of the number of new infections that occurred in state i in
year j Xi(j)
is the population at risk for TB infection in state i in year j. Step 2:
Estimation of Ii(j), the number of new TB infections: Let: Ai(j)
be the total number of adult TB cases reported to CDC by state i in year j. A(j)
be the total number of adult TB cases reported to CDC by all states in year
j. Pi(j)
be the estimated prevalence of adult TB infection in state i during year j. Ri
be the ratio of the number of adult TB cases reported in 1993 to the number
of adult cases reported in 1994 in state i. The
number of TB cases reported in 1994 can be expressed as a function of TB
infections expected to have progressed to active disease, by the following
formula: where
j ranges from 1919 to 1992. The quantity inside the summation symbol is the
sum of all people who were infected with TB between 1919 and 1992 and are
still alive in 1994. This summation can be approximated by the prevalence of
TB infection in 1992, Pi(1992). Therefore, the number of active TB
cases reported in 1994 can be expressed as: Further,
if we assume that the number of new infections is directly proportional to
the number of active cases, then Ii(1993) can be expressed as
follows: and
(2) can be expressed as: then
solving for Ii(1994) becomes: (2) Step 3:
Estimation of Xi(1994): Where: Ni
is the adult population for state i as reported by U.S. Census in 1994. Pi(1993)
is the estimated number of infected adults in state i in 1993 (i.e.,
prevalence of TB infection in state i among adults). To
estimate the number of adults currently at risk for TB infection in each
state, the number of already infected adults (i.e., prevalence of TB
infection Pi in 1993) is subtracted from the adult population in
1994. Step 4:
Estimation of population currently infected as of 1993 by state, Pi(1993): The
prevalence of TB infection in each state is estimated as a function of TB
infection prevalence in the U.S. in 1993 and the percent TB case rate for
each state. Where: P(1993)
is the prevalence of TB infections in the U.S. in 1993 (Ex. 7-66) and A(1993)
is the total number of adult TB cases reported in 1993. Estimates
of TB infection prevalence in the U.S. were developed for OSHA by Dr.
Christopher Murray of the Harvard Center for Population and Development
Studies and are presented in Table V-6 (Ex. 7-267). The mathematical model
used by Dr. Murray to estimate TB infection prevalence has been designed to
capture the transmission dynamics of TB by modeling transfers between a
series of age-stratified compartments using a system of differential
equations. The model adjusts for various epidemiological factors known to
influence the course of active TB, such as onset of infection (i.e., old vs.
new infections) and the impact of immigration rates and the HIV epidemic. However,
it does not differentiate among gender or race categories. The model has been
successfully validated using actual epidemiological data on active TB from
1965 to 1994. The estimates of TB prevalence rates presented here are
specific for adults (i.e., older than 18 years of age), which make them more
appropriate for estimating risk of transmission in an occupational setting. To
estimate the number of previously infected adults in each state (Pi),
the estimated national TB prevalence figure was multiplied by the active
cases for each state and divided by the total number of active cases reported
[see equation (7)] (i.e., the national prevalence estimate was apportioned
among the states based on each state's percent contribution to active TB reported
for 1993). To estimate the number of adults at risk of TB infection, (Xi),
the number of already infected adults was subtracted from the adult
population estimate for each state (see equation (6)). The number of new
infections expected to have occurred in 1994 was estimated using equation
(5). The
background rate of TB infection for 1994 was then estimated by dividing the
number of new infections (Ii) by the number of susceptible adults
in each state (Xi) (see equation (1)). Results
on estimated TB background annual infection rates for each state are
presented in Table V-7(a) -- Table V-7(c). In Table V-7(a) TB infection rates
are based on an average value of TB infection prevalence, as estimated by Dr.
Murray, in the U.S. (i.e., 12,667,062). In Table V-7(b), infection rates are
based on the minimum value of TB infection prevalence in the U.S. (i.e.,
12,037,524). In Table V-7(c), infection rates are based on the maximum value
of TB infection prevalence in the U.S. (i.e., 13,296,599). An overall range
of background annual TB infection rates was constructed by combining all
three sets of infection rates and was estimated to be between 0.194 and 3.542
per 1,000 individuals at risk of TB infection, with a weighted average of
1.46 per 1,000 using state population size as weights. Step 5
Model validation: An
alternative, but less sophisticated, way to estimate annual risk of
infection, if prevalence is known in a specific age group, is to use the
following formula: Annual
Rate of Infection = -ln(1-P)/d (8) Where: P
is the percent prevalence of infection and d
is the average age of the population (Ex. 7-265). In
order to validate the model used by OSHA to estimate background infection
rates, estimates of TB infection prevalence for 1994 were used to calculate
predicted infection rates using equation (8). Based on Murray's model, TB
infection prevalence is expected to range from 6.31 % to 6.97 % in 1994 among
adults (18+). Using these figures and assuming the average age to be 45
years, formula (8) predicts that infection rates can range from 1.45 to 1.61
per 1,000. These results are in close agreement with OSHA's weighted average
estimate of the national TB infection rate, which is 1.46 per 1,000. 4.
Occupational Risk Estimations OSHA
used the three different data sources to obtain estimates of risk of TB
infection for health care employees: the Washington State data, the North
Carolina study, and the NIOSH Health Hazard Evaluation (HHE) from Jackson
Memorial Hospital (Exs. 7-263, 7-7, 7-108). The Washington State data
represent workplaces located in low TB prevalence areas, where TB infection
control measures and engineering controls are required by state health
regulations. The North Carolina data represent workplaces located in areas
with moderate TB prevalence and inadequate TB infection control programs. Finally,
the Jackson Memorial Hospital data are representative of county hospitals
serving high-risk patients whose employees have a high frequency of exposure
to infectious TB. These data sources provide information on the magnitude of
the expected excess risk in three different environments, and are used to
provide a range of possible values of excess risk. Based
on the Washington State data, the annual risk is expected to be 1.5 times the
background rate for hospital employees, approximately 11 times the background
rate for long-term care employees, 6 times the background rate for home <<health care
workers>>,
and double the background rate for home care employees. Based on the North
Carolina data, the annual risk is expected to be approximately 5 times the
background rate. Based on the Jackson Memorial Hospital data, the annual risk
is expected to be approximately 9 times the background. Estimates
of expected excess risk of TB infection for workers with occupational
exposure by state are calculated by applying the excess relative risk ratios,
derived from the three occupational studies, to the overall background rate
of infection for each state and are presented in table V-8(a) -- table
V-8(c). A range of excess risk of TB infection due to occupational exposure
is constructed by using the minimum and maximum estimates of excess risk
among all states for each data source. These results are presented in table
V-9 and table V-10 for workers in hospitals and for workers in other work
settings, respectively. Lifetime
estimates of the excess risk of TB infection were estimated based on the
annual excess risk by using the formula {1-(1-p) 45}, where p is
the annual excess risk. Lifetime excess estimates of TB infection are
presented in table V-9 and table V-10. Lifetime risk estimates of developing
active TB are calculated from lifetime risk estimates of TB infection
assuming that, once infected, there is a 10 % likelihood of progressing to
active TB; these estimates are presented in table V-11 and table V-12. Further,
the risk of death caused by TB is calculated from the lifetime estimates of
active TB using OSHA's estimate of the TB case fatality rate (also presented
in table V-11 and table V-12). The methodology used to estimate a TB case fatality
rate is presented below. As
outlined in the Health Effects section, several possible outcomes are
possible following an infection. Approximately 90 % of all infections never
progress to active disease. An estimated 10 % of infections is expected to
progress to active disease; most of these cases are successfully treated. However,
a percentage of active TB cases develop further complications. Approximately
7.8 % of active TB cases may take a more severe clinical course and lead to
death. The TB case fatality rate was estimated using information on reported
deaths caused by TB from table 8-5 of the Vital Statistics for the U.S. and
cases of TB reported in CDC's TB Surveillance system for 1989 through 1991
(Exs. 7-270, 7-264). As shown in table V-13, the TB case death rate ranged
from 69.94 to 89.18 per 1,000 with a 3-year average of 77.85 per 1,000 TB
cases. The Agency used the 3-year average (77.85 per 1,000) for its estimate
of deaths caused by TB. This estimate is in close agreement with published
results from a retrospective cohort study conducted in Los Angeles County on
TB cases in 1990 (Ex. 7-268). In this study, all confirmed TB cases reported
in the county in 1990 were tracked and the number of deaths where TB was the
direct or contributing cause was ascertained. "Contributing cause"
was defined as a case of TB of such severity that it would have caused the
death of the patient had the primary illness not caused death earlier. Of the
1,724 cases included in the study, TB was considered the cause of death or
the contributing cause of death in 135 cases (78.31 per 1,000). National
estimates of annual and lifetime risk for TB infection, active disease and
death caused by TB due to occupational exposure are computed as weighted
averages of the state estimates and are presented in table V-14. (a)
Risk Estimates for Hospital Employees: Logistic regression analysis of
the Washington state hospital data indicated an increase in annual risk (47 %
above background) for employees with potential exposure to TB. For this
particular analysis the control group was defined as those hospitals with
no-known TB patients that are located in counties that did not report any
active TB cases in 1994. However, an increased risk of 47 % above background
in the annual infection rate is expected to produce a range of 4 to 72 TB
infections per 1000 exposed workers in a working lifetime, which could result
in as many as 7 cases of active TB and approximately 1 death per 1,000
exposed workers. Based
on the survey of hospitals in North Carolina's western region, the expected
overall risk due to occupational exposure is estimated to be 4 times the
background rate. This results in an expected range of lifetime risk between
34 and 472 infections per 1,000 employees at risk for TB infection. Lifetime
estimates of active TB cases resulting from these infections are expected to
range between 3 and 47, resulting in as many as 4 deaths per 1,000 exposed
employees at risk of TB infection. As done previously, the North Carolina
study results were adjusted to reflect 1994 TB disease trends. Based
on the data from Jackson Memorial Hospital, the overall risk due to
occupational exposure is estimated to be 8 times the background rate. This
results in an expected range of lifetime risk between 67 and 723 infections
per 1,000 employees at risk. Lifetime estimates of the number of active TB
case per 100 exposed workers are expected to range between 7 and 72,
resulting in as many as 6 deaths per 1,000 exposed employees at risk for TB
infection. In
summary, table V-9 and table V-14 show that the annual occupational risk of
infection is expected to range: (a)
From .09 to 1.66 with a weighted average of 0.68 per 1,000 for workplaces
located in relatively low TB prevalence areas, and where TB infection
measures and engineering controls are required; (b)
From 0.77 to 14.1 with a weighted average of 5.7 per 1,000 for workplaces
located in areas with moderate TB prevalence and inadequate TB control
programs; and (c)
From 1.54 to 28 with a weighted average of 11.8 per 1,000 for workplaces
located in high TB prevalence areas, serving high risk patients, with high
frequency of exposure to infectious TB. Similarly,
the lifetime occupational risk is expected to range: (a)
From 4 to 72 with a weighted average of 30 per 1,000 for workplaces located
in relatively low TB prevalence areas, and where TB infection measures and
engineering controls are required; (b)
From 34 to 472 with a weighted average of 219 per 1,000 for workplaces
located in areas with moderate TB prevalence and inadequate TB control
programs; and (c)
From 67 to 723 with a weighted average of 386 per 1,000 for workplaces
located in high TB prevalence areas, serving high risk patients, with high
frequency of exposure to infectious TB. Risk
estimates derived from either study (Washington State or North Carolina)
represent an overall rate of occupational risk, because both studies include
PPD skin testing results from the entire hospital employee population,
whereas the Jackson Memorial study addresses the occupational risk to workers
where exposure to infectious TB is highly probable. Although
the exact compliance rate is not known, hospitals in Washington State have
been required to implement the CDC TB guidelines with respect to engineering
controls (requiring isolation rooms with negative pressure) and infection
control measures (advocating early patient identification, employee training,
respiratory protection, and PPD testing). Neither
the facilities in North Carolina nor Jackson Memorial had engineering
controls fully implemented at the time these data were collected. Early
identification of suspect TB patients has always been recommended in North
Carolina. However, engineering controls in isolation rooms were either not
present or did not function properly because of modifications in the physical
structure of the building (i.e., isolation rooms had been subdivided using
partitions, air ducts had been re-directed because of remodeling, etc.). Tuberculin
skin testing was very inconsistent and sporadic. In addition, employee
training and use of respiratory protection were not emphasized. By
1991, Jackson Memorial had most of the engineering controls in place in the
HIV ward (where the first outbreak took place) and in selected areas with
high TB exposure, but not in the entire hospital. However, the staff training
program was still being developed and respiratory protection was not always
adequate. Although exposures had been greatly reduced, "high risk"
procedures were still being performed in certain areas of the hospital
without adequate engineering controls, such as the Special Immunology clinic
where HIV-TB patients received pentamidine treatments. Like the hospitals in
the North Carolina study, Jackson Memorial represents a working environment
that serves a patient population known to have high TB prevalence. In
addition, Jackson Memorial only tested employees with patient contact in
areas where active TB had been detected. (b)
Risk Estimates for Workers in Other Work Settings: In long-term care
facilities for the elderly there is also a significantly increased likelihood
that employees will encounter individuals with infectious TB. Persons over
the age of 65 constitute a large proportion of the TB cases in the United
States. In 1987, CDC reported that persons aged 65 and over accounted for 27
% (6150) of the reported cases of active TB in the U.S., although they
account for only 12 % of the U.S. population. Many of these individuals were
infected in the past and advancing age and decreasing immunocompetence have
caused them to develop active disease. In 1990 the CDC estimated that
approximately 10 million people were infected with TB. As the U.S. population
steadily ages, many of these latent infections may progress to active
disease. Because elderly persons represent a large proportion of the nation's
nursing home residents and because the elderly represent a large proportion
of the active cases of TB, there is an increased likelihood that employees at
long-term care facilities for the elderly will encounter individuals with
infectious TB. Similarly,
there are other occupational settings that serve high-risk client populations
and thus have an increased likelihood of encountering individuals with
infectious TB. For example, hospices, emergency medical services, and
home-health care services provide services to client populations similar to
those in hospitals and thus are likely to experience similar risks. OSHA
used information from the 1994 Washington state PPD skin testing survey to
estimate occupational risk for workers in long-term care, home health care,
and home care. Annual estimates of excess risk for TB infection are presented
in TABLE V-10 and lifetime estimates for TB infection, active TB, and death
caused by occupational TB are presented in TABLE V-12. Based
on the Washington State data, the overall annual excess risk for TB infection
is estimated to be 10-fold over background for workers in long-term care. This
results in an expected range of lifetime risk of between 85 and 800
infections per 1,000 employees at risk for TB infection. Lifetime estimates
of the number of active TB cases resulting from these infections range from 9
to 81 and are projected to cause as many as 6 deaths per 1,000 exposed
employees at risk of TB infection. Similarly, the overall annual excess risk
of TB infection for workers in home health care is estimated to be
approximately 500 % above background. This results in an expected range of
lifetime risk of between 41 and 536 infections per 1,000 employees at risk
for TB infection. Lifetime estimates of the number of active TB cases range
from 4 to 54 per 1,000, and are projected to cause as many as 4 deaths per
1,000 exposed employees at risk of TB infection. Similarly, the overall
annual excess risk of TB infection for workers in home care is estimated to
be approximately 100 % above background. This results in an expected range of
lifetime risk of between 10 and 164 infections per 1,000 employees at risk
for TB infection. Lifetime estimates of the number of active TB cases range
from 1 to 16, and are expected to result in approximately 1 death per 1,000
exposed employees at risk of TB infection. Clearly,
employees in all three groups (long-term care for the elderly, home health
care, and home care) have higher risks than hospital employees in Washington.
This could be attributed, in part, to the lack of engineering controls in
these work settings. That respirators may be used only intermittently may
also play a role. Although workers in these three groups are encouraged by
local health authorities to use respiratory protection while tending to a
suspect TB patient, the actual rate of respirator usage is difficult to
ascertain. A third factor that may contribute to higher risk in these work
settings is delayed identification of suspect TB patients due to confounding
symptoms presented by the individuals. For example, many long-term care
residents exhibit symptoms of persistent coughing from decades of smoking. Consequently,
an individual in long-term care with a persistent cough may be infectious for
several days before he or she is identified as having suspected infectious
TB. Qualitative Assessment of Risk for Other Occupational Settings The
quantitative estimates of the risk of TB infection discussed above are based
primarily upon data from hospitals and selected other health care settings. Data
from hospitals and certain health care settings were selected because OSHA
believes that these data represent the best information available to the
Agency for purposes of quantifying the occupational risks of TB infection and
disease. However, as discussed above, it is their exposure to aerosolized M.
tuberculosis that places these workers at risk of infection and not
factors unique to these particular kinds of health care activities. Thus,
OSHA believes that the risk estimates derived from hospitals and selected
other work settings can be used to describe the potential range of risks for
other health care and other occupational settings in which workers can
reasonably anticipate frequent and substantial exposure to aerosolized M. tuberculosis. In
order to extrapolate the quantitative risk estimates calculated for hospital
employees and other selected health care settings, OSHA, as a first step,
identified risk factors that place employees at risk of exposure. Some amount
of exposure to TB could occur in any workplace in the United States. TB is an
infectious disease that occurs in the community and thus, individuals may
bring the disease into their own workplace or to other businesses or work
settings that they may visit. However, there are particular kinds of work
settings where risk factors are present that substantially increase the
likelihood that employees will be frequently exposed to aerosolized M.
tuberculosis. First among these factors is the increased likelihood of
exposure to individuals with active, infectious TB. Individuals who are
infected with TB have a higher risk of developing active TB if they are (1)
immunocompromised (e.g., elderly, undergoing chemotherapy, HIV
positive), (2) intravenous drug users, or (3) medically underserved and of
generally poor health status (Exs. 6-93 and 7-50). Thus, in work settings in
which the client population is composed of a high proportion of individuals
who are infected with TB, are immunocompromised, are intravenous drug users
or are of poor general health status, there is a greatly increased likelihood
that employees will routinely encounter individuals with infectious TB and be
exposed to aerosolized M. tuberculosis. A second factor that places
employees at high risk of exposure to aerosolized M. tuberculosis is
the performance of high-hazard procedures, i.e., procedures performed on
individuals with suspected or confirmed infectious TB where there is a high
likelihood of the generation of droplet nuclei. A third factor that places employees
at risk of exposure is the environmental conditions at the work setting. Work
settings that have overcrowded conditions or poor ventilation will facilitate
the transmission of TB. Thus, given that a case of infectious TB does occur,
the conditions at the work setting itself may promote the transmission of
disease to employees who share airspace with the individual(s) with
infectious TB. The
second step in extrapolating the quantitative risks is to identify the types
of work settings which have some or all of the risk factors outlined above. Once
these work settings have been identified, OSHA believes that it is reasonable
to assume that the quantitative risk estimates calculated for hospitals and
other selected health care settings can be used to describe the risks in the
identified work settings. Correctional Facilities Employees
in correctional facilities or other facilities that house inmates or
detainees have an increased likelihood of frequent exposure to individuals
with infectious TB. Many correctional facilities have a higher incidence of
TB cases in comparison to the incidence in the general population. In 1985,
the CDC estimated that the incidence of TB among inmates of correctional
facilities was more than three times higher than that for nonincarcerated
adults aged 15-64 (Ex. 3-33). In particular, in states such as New Jersey,
New York, and California, the increased incidence of annual TB cases in
correctional facilities ranged from 6 to 11 times greater than that of the
general population for their respective states (Exs. 7-80 and 3-33). A major
factor in the increased incidence of TB cases in correctional facilities is
the fact that the population of correctional facilities is over-represented
by individuals who are at greater risk of developing active disease, e.g.,
persons from poor and minority groups who may suffer from poor nutritional
status and poor health care, intravenous drug users, and persons infected
with HIV. Similarly, certain types of correctional facilities, such as holding
facilities associated with the Immigration and Naturalization Service, may
have inmates/detainees from countries with a high incidence of TB. For
foreign-born persons arriving in the U.S., the case rate of TB in 1989 was
estimated to be 124 per 100,000, compared to an overall TB case rate of 9.5
per 100,000 for the U.S. (Ex. 6-26). Moreover, in the period from 1986 to
1989, 22 % of all reported cases of TB disease occurred in the foreign-born
population. Given the increased prevalence of individuals at risk for
developing active TB, there is an increased likelihood that employees working
in these facilities will encounter individuals with infectious TB. In
addition, environmental factors such as overcrowding and poor ventilation
facilitate the transmission of TB. Thus, given that a case of infectious TB
does occur, the conditions in the facility itself promote the transmission of
the disease to other inmates and employees in the facility who share
airspace. As
discussed in the Health Effects section, a number of outbreak investigations
(Exs. 6-5, 6-6) have shown that where there has been exposure to aerosolized M.
tuberculosis in correctional facilities, the failure to promptly identify
individuals with infectious TB and provide appropriate infection control
measures has resulted in employees being infected with TB. These studies
demonstrate that, as in hospitals or health care settings, where there is
exposure to aerosolized TB bacilli and where effective control measures are
not implemented, exposed employees are at risk of infection. Thus, estimates
based on the risk observed among employees in hospitals and in selected other
work settings that involve an increased likelihood of exposure can be
appropriately applied to employees in correctional facilities. Recently,
scientists at NIOSH have completed a prospective study of the incidence of TB
infection among New York State correctional facilities employees (Ex. 7-288).
This study is the first prospective study of TB infection among employees in
correctional facilities in an entire state. Other studies have reported on
contact investigations, which seek to identify recent close contacts with an
index case and determine who might subsequently have been infected. Studies
based on contact investigations have the advantage of a good definition of
potential for exposure and they serve to identify infected persons for public
health purposes. On the other hand, prospective studies of an entire working
group have the advantage of covering the entire population potentially at
risk, of considering all inmate cases simultaneously as potential sources of
infection, and, most importantly, of permitting the calculation of incidence
rates and risk attributable to occupational exposure. Following
an outbreak of active TB among inmates that resulted in transmission to
employees in 1991, the state of New York instituted a mandatory annual
tuberculin skin testing program to detect TB infection among employees. The
authors used data from the first two years of testing to estimate the
incidence of TB infection among 24,487 employees of the NY Department of
Corrections. Subjects included in the study had to have two sequential PPD
skin tests, have a negative test the first year, and have complete
demographic information. The overall conversion rate was estimated to be 1.9
%. Preliminary results show that after controlling for age, ethnicity,
gender, and residence in New York City, corrections offices and medical
personnel, working in prisons with inmate active TB cases, had odds ratios of
TB infection of 1.64 and 2.39, respectively, compared to maintenance and
clerical personnel who had little opportunity for prisoner contact. Based on
these results, the annual excess risk due to occupational exposure is
estimated to be 1.22 % and 2.64 % for corrections officers and medical
personnel, respectively. This translates into lifetime occupational risks of
423 and 700 per 1,000 exposed employees, respectively. In prisons with no
known inmate TB cases, there were no significant differences in TB infection
rates among employees in different job categories. Homeless Shelters Employees
in homeless shelters also have a significantly increased likelihood of
frequent exposure. A high prevalence of TB infection and disease is common in
many homeless shelters. Screening in selected shelters has shown the
prevalence of TB infection to range from 18 to 51 % (Ex. 6-15). Many shelter
residents also possess characteristics that impair their immunity and thus
place them at greater risk of developing active disease. For example,
homeless persons often suffer from poor nutrition and poor overall health
status, and they also have poor access to health care. In addition, they may
suffer from alcoholism, drug abuse and infection with HIV. Screening of
selected shelters has shown the prevalence of active TB disease to range from
1.6 to 6.8 % (Ex. 6-15). Thus, there is an increased likelihood that
employees at homeless shelters will frequently encounter individuals with
infectious TB in the course of their work. In
addition, as in the case for correctional facilities, homeless shelters also
tend to be overcrowded and have poor ventilation, factors that promote the
transmission of disease and place shelter residents and employees at risk of
infection. Outbreaks reported among homeless shelters (Exs. 7-51, 7-75, 7-73,
6-25) also provide evidence that where there is exposure to individuals with
infectious TB and effective infection control measures are not implemented,
employees are at risk of infection. It is reasonable to assume, therefore,
that risk estimates calculated for hospital employees who have an increased
likelihood of exposure to individuals with infectious TB can be used to
estimate the risks for homeless shelter employees. Facilities That Provide Treatment for Drug Abuse Employees
in facilities that provide treatment for drug abuse have an increased
likelihood of frequent exposure to individuals with infectious TB. Surveys of
selected U.S. cities by the CDC have shown the prevalence of TB infection
among the clients of drug treatment centers to range from approximately 10 %
to 13 % (Ex. 6-8). Clients of these centers are also generally at higher risk
of developing active disease. The clients typically come from medically
underserved populations and may suffer from poor overall health status. As
discussed in the Health Effects section, drug dependence has also been shown
to be a possible risk factor in the development of active TB. Moreover, many
of the drug treatment center clients are intravenous drug users and are
infected with HIV, placing these individuals at an increased risk of
developing active TB. Given these risk factors for the clients served at drug
treatment centers, there is an increased likelihood that employees in these
work settings will be exposed frequently to individuals with infectious TB. Medical Laboratories Medical
laboratory work is a recognized source of occupational hazards. CDC considers
workers in medical laboratories that handle M. tuberculosis to be at
high risk for occupational transmission of TB either because of the volume of
material handled by routine diagnostic laboratories or the high
concentrations of pathogenic agents often handled in research laboratories. Few
surveys of laboratory-acquired infections have been undertaken; most reports
are of small outbreaks in specific laboratories. Sulkin and Pike's study of
5,000 laboratories suggested that brucellosis, tuberculosis, hepatitis, and
enteric diseases are among the most common laboratory-acquired infections
(Ex. 7-289). In 1957, Reid noted that British medical laboratory workers had
a risk of acquiring tuberculosis two to nine times that of the general
population (Ex. 7-289). This result was validated in 1971 by Harrington and
Channon in their study of medical laboratories (Ex. 7-289). A retrospective
postal survey of approximately 21,000 medical laboratory workers in England
and Wales showed a five-times increased risk of developing active TB among
these workers as compared with the general population. Technicians were at
greater risk, especially if they worked in anatomy departments. A similar
survey carried out in 1973 of 3,000 Scottish medical laboratory workers
corroborates the results from England and Wales. Three cases, one doctor and
two technicians, were noted in the 1973 survey, which resulted in an overall
incidence rate of 109 per 100,000 person-years. The general population
incidence rate for active TB was 26 per 100,000 person-years, giving a risk
ratio of 4.2 (Ex. 7-289). The
studies reviewed in this section indicate that workers in medical
laboratories with potential for exposure to M. tuberculosis during the
course of their work have a several-fold (ranging from 2- to 9-fold)
increased risk of developing active disease compared with the risk to the
general population. Although these studies were conducted over two decades
ago, they represent the most recent data available to the Agency, and OSHA
has no reason to believe that the conditions giving rise to the risk of
infection at that time have changed substantially in the interim. The Agency
is not aware of any more current data on transmission rates in medical
laboratories. OSHA solicits information on additional studies addressing
occupational exposure to active TB in laboratories; such studies would then
be considered by OSHA in the development of a final rule. Other Work Settings and Activities In
addition to the information available for correctional facilities, homeless
shelters, and facilities that provide treatment for drug abuse, there are
other work settings and activities where there is an increased likelihood of
frequent exposure to aerosolized M. tuberculosis. For example,
hospices serve client populations similar to those of hospitals and perform
similar services for these individuals. Individuals who receive care in
hospices are likely to suffer from medical conditions (e.g., HIV
disease, end-stage renal disease, certain cancers) that increase their
likelihood of developing active TB disease once infected. Thus, employees
providing hospice care have an increased likelihood of being exposed to
aerosolized M. tuberculosis. CDC has recommended that hospices follow
the same guidelines for controlling TB that hospitals follow. Emergency
medical service employees also have an increased likelihood of encountering
individuals with infectious TB. Like hospices, emergency medical services
cater to the same high risk client populations as hospitals. Moreover,
emergency medical services are often used to transport individuals identified
with suspected or confirmed infectious TB from various types of health care
settings to facilities with isolation capabilities. In
addition, other types of services (e.g., social services, legal
counsel, education) are provided to individuals who have been identified as
having suspected or confirmed infectious TB and have been placed in isolation
or confined to their homes. Employees who provide social welfare services,
teaching, law enforcement or legal services to those individuals who are in
AFB isolation are exposed to aerosolized M. tuberculosis. In
particular, employees performing high-hazard procedures are likely to
generate aerosolized M. tuberculosis by virtue of the procedure
itself. Thus, employees providing these types of services also have an
increased likelihood of exposure to aerosolized M. tuberculosis and
are therefore likely to experience risks similar to those described above for
hospital workers. Although
they do not have contact with individuals with infectious TB, employees who
repair and maintain ventilation systems which carry air contaminated with M.
tuberculosis and employees in laboratories who manipulate tissue samples
or cultures contaminated with M. tuberculosis also have an increased
likelihood of being exposed to aerosolized M. tuberculosis. Like
employees in the work settings discussed above, these employees have an
increased risk of frequent exposure to aerosolized M. tuberculosis. Therefore,
OSHA believes that the quantitative risk estimates derived from data observed
among <<health care
workers>>
in the hospital setting can be generally used to describe the potential range
of risks for workers in other occupational settings where there is a
reasonable anticipation of exposure to aerosolized M. tuberculosis. The
reasonableness of this assumption is supported by the overall weight of
evidence of the available health data. As discussed in the Health Effects
section, epidemiological studies, case reports and outbreak investigations
have shown that in correctional facilities, homeless shelters, long-term care
facilities for the elderly, drug treatment centers, and laboratories where
appropriate TB infection control programs have not been implemented,
employees have become infected with TB as a result of occupational exposure
to individuals with infectious TB or to other sources of aerosolized M.
tuberculosis. Thus, although the data on employee conversion rates in
other work settings cannot be used to directly quantify the occupational risk
of infection for those work settings, there is strong evidence that employees
in various work settings other than hospitals can reasonably be anticipated
to have exposure to aerosolized M. tuberculosis and that TB can be
transmitted in these workplaces when appropriate TB infection control
programs are not implemented. VI. Significance of Risk Section
6(b)(5) of the OSH Act vests authority in the Secretary of Labor to issue
health standards. This section provides, in part, that: The
Secretary, in promulgating standards dealing with toxic materials or harmful
physical agents under this subsection, shall set the standard which most
adequately assures, to the extent feasible, on the basis of the best
available evidence, that no employee will suffer impairment of health or
functional capacity even if such employee has regular exposure to the hazard
dealt with by such standard for the period of his working life. OSHA's
overall analytical approach to making a determination that workplace exposure
to certain hazardous conditions presents a significant risk of material
impairment of health is a four step process consistent with interpretations
of the OSH Act and rational, objective policy formulation. In the first step,
a quantitative risk assessment is performed where possible and considered
with other relevant information to determine whether the substance to be
regulated poses a significant risk to workers. In the second step, OSHA
considers which, if any, of the regulatory alternatives being considered will
substantially reduce the risk. In the third step, OSHA examines the body of
"best available evidence" on the effects of the substance to be
regulated to set the most protective requirements that are both
technologically and economically feasible. In the fourth and final step, OSHA
considers the most cost-effective way to achieve the objective. In
the Benzene decision, the Supreme Court indicated when a reasonable person
might consider the risk significant and take steps to decrease it. The Court
stated: It
is the Agency's responsibility to determine in the first instance what it
considers to be "significant" risk. Some risks are plainly
acceptable and others are plainly unacceptable. If, for example, the odds are
one in a billion that a person will die from cancer by taking a drink of chlorinated
water, the risk could not be considered significant. On the other hand, if
the odds are one in a thousand that regular inhalation of gasoline vapors
that are 2 % benzene will be fatal, a reasonable person might well consider
the risk significant and take the appropriate steps to decrease or eliminate
it. (I.U.D. v. A.P.I.), 448 U.S. at 655). The
Court indicated that "while the Agency must support its findings that a
certain level of risk exists with substantial evidence, we recognize that its
determination that a particular level of risk is `significant' will be based
largely on policy considerations." The Court added that the significant
risk determination required by the OSH Act is "not a mathematical
straitjacket" and that "OSHA is not required to support its
findings with anything approaching scientific certainty." The Court
ruled that "a reviewing court (is) to give OSHA some leeway where its
findings must be made on the frontiers of scientific knowledge and that the
Agency is free to use conservative assumptions in interpreting the data with
respect to carcinogens, risking error on the side of overprotection rather
than underprotection." (448 U.S. at 655, 656). As
a part of the overall significant risk determination, OSHA considers a number
of factors. These include the type of risk presented, the quality of the
underlying data, the reasonableness of the risk assessments, and the
statistical significance of the findings. The
hazards presented by the transmission of tuberculosis, such as infection,
active disease, and death are very serious, as detailed above in the section
on health effects. If untreated, 40-60 % of TB cases have been estimated to
result in death (Exs. 5-80, 7-50, 7-66). Fortunately, TB is a treatable
disease. The introduction of antibiotic drugs for TB has helped to reduce the
mortality rate by 94 % since 1953 (Ex. 5-80). However, TB is still a fatal
disease in some cases. From 1989-1991 CDC reported 5,452 deaths among adults
from TB (see TABLE V-13, Risk Assessment section). In addition, there has
been an increase in certain forms of drug-resistant TB, such as MDR-TB, in
which the tuberculosis bacilli are resistant to one or more of the front line
drugs such as isoniazid and rifampin, two of the most effective anti-TB
drugs. The information available today is not adequate to estimate the future
course of MDR-TB, but the reduction in the potential of transmitting this
deadly form of the disease is itself another benefit of this standard. The
current data indicate that among MDR-TB cases, the risk of death is increased
compared to drug-susceptible forms of the disease. A CDC investigation of 8
outbreaks of MDR-TB revealed that among 253 people infected with MDR-TB, 75 %
died within a period 4 to 16 weeks after the time of diagnosis (Ex. 38-A). MDR-TB
may be treated, but due to the difficulty in finding adequate therapy which
will control the bacilli's growth, individuals with this form of the disease
may remain infectious for longer periods of time, requiring longer periods of
hospitalization, additional lost worktime, and an increased likelihood of
spreading TB infection to others until treatment renders the patient
non-infectious. Because of the difficulty in controlling these drug-resistant
forms of the disease with antibiotics, progressive lung destruction may
progress to the point where it is necessary to remove portions of the lung to
treat the advance of the disease. The
OSH Act directs the Agency to set standards that will adequately assure, to
the extent feasible, that no employee will suffer "material impairment
of health or functional capacity." TB infection represents a material
impairment of health that may lead to active disease, tissue and organ
damage, and death. Although infected individuals may not present any signs or
symptoms of active disease, being infected with TB bacilli is a serious
threat to the health status of the infected individual. Individuals who are
infected have a 10 % chance of developing active disease at some point in
their life, a risk they would not have had without being infected. The risk
of developing active disease is even greater for individuals who are
immunocompromised, due to any of a large number of factors. For example,
individuals infected with HIV have been estimated as having an 8-10 % risk per
year of developing active disease (Ex. 4B). In
addition, since infected individuals commonly undergo treatment with anti-TB
drugs to prevent the onset of active disease, they face the additional risk
of serious side effects associated with the highly toxic drugs used to treat
TB. Preventive treatment with isoniazid, one of the drugs commonly used to
treat TB infection, has been shown in some cases to result in death from
hepatitis or has damaged the infected person's liver to the extent that liver
transplantation was performed (Ex. 6-10). Thus, the health hazards associated
with TB infection clearly constitute material impairment of health. Clinical
illness, i.e., active disease, also clearly constitutes material impairment
of health. Left untreated, 40 to 60 percent of active cases may lead to death
(Exs. 7-50, 7-66, 7-80). Individuals with active disease may be infectious
for various periods of time and often must be hospitalized. Active disease is
marked by a chronic and progressive destruction of the tissues and organs
infected with the bacteria. Active TB disease is usually found in the lungs
(i.e., pulmonary tuberculosis). Long-term damage can result even when cases
of TB are cured; a common result of TB is reduced lung function (impaired
breathing) due to lung damage (Ex. 7-50, pp. 30-31). Inflammatory responses
caused by the disease produce weakness, fever, chest pain, cough, and, when
blood vessels are eroded, bloody sputum. Also, many individuals have
drenching night sweats over the upper part of the body several times a week. The
intensity of the disease varies, ranging from minimal symptoms of disease to
massive involvement of many tissues, with extensive cavitation and
debilitating constitutional and respiratory problems. Long-term damage can
also result from extrapulmonary forms of active disease; such damage may
include mental impairment from meningitis (infection of membranes surrounding
the brain and spinal cord) and spinal deformity and leg weakness due to
infection of the vertebrae (i.e., skeletal TB) (Ex. 7-50, p. 31). Active
disease is treatable but it must be treated with potent drugs that have to be
taken for long periods of time. The drugs currently used to treat active TB
disease may be toxic to other parts of the body. Commonly reported side
effects of anti-TB drugs include hepatitis, peripheral neuropathy, optic
neuritis, ototoxicity and renal toxicity (Ex. 7-93). Active disease resulting
from infection with MDR-TB is of even greater concern due to the inability to
find adequate drug regimens. Although OSHA has not been able to precisely
quantify the increase in incidence of MDR-TB, the number of cases of MDR-TB
is clearly on the rise. In these cases, individuals may remain infectious for
longer periods of time and may suffer more long-term damage from the chronic
progression of the disease until adequate therapy can be identified. In
this standard, OSHA has presented quantitative estimates of the lifetime risk
of TB infection, active disease and death from occupational exposure to M.
tuberculosis. Qualitative evidence of occupational transmission is also
included in OSHA's risk assessment. In
preparing its quantitative risk assessment, OSHA began by seeking out
occupational data associated with TB infection incidence in order to calculate
an estimate of risk for TB infection attributable to occupational exposure
for all U.S. workers. Unfortunately, an overall national estimate of risk for
TB infection attributable to occupational exposure is not available. CDC,
which collects and publishes the number of active TB cases reported
nationwide each year, does not publish occupational data associated with the
incidence of TB infection and active TB on a nationwide basis. There has been
some effort to include occupational information on the TB reporting forms,
but only a limited number of states are currently using the new forms and
capturing occupational information in a systematic way. In the absence of a
national database, OSHA used two statewide studies, from North Carolina and
Washington (Exs. 7-7, 7-263), and data from an individual hospital, Jackson
Memorial Hospital (Ex. 7-108), on conversion rates of TB infection for
workers in hospitals. The Washington State database also contained
information on three additional occupational groups: long-term care, home
health care and home care employees. OSHA used these data to model average TB
infection rates and estimate the range of expected risks in the U.S. among
workers with occupational exposure to TB. The
conversion rates in the selected studies were used to estimate the annual
excess relative risk due to occupational exposure, which was expressed as the
percent increase of infection above each study's control group. In order to
estimate an overall range of occupational risk of TB infection, taking into
account regional differences in TB prevalence in the U.S. and indirectly
adjusting for factors such as socio-economic status, which might influence
the rate of TB observed in different parts of the country, OSHA: (1)
Estimated background rates of infection for each state by assuming that the
number of new infections is functionally related to the number of active
cases reported by the state each year (i.e., the distribution of new
infections is directly proportional to the distribution of active cases), and
2) applied estimates of the annual excess relative risk, derived from the
occupational studies, to the state background rates to calculate estimates of
excess risk due to occupational exposure by state. Thus, the excess
occupational risk estimates are actually calculated from the three available
studies, on a relative increase basis, and these relative increases are
multiplied by background rates for each state to derive estimates of excess
occupational risk by state. The state estimates are then used to derive a
national estimate of annual occupational risk of TB infection. Given an
annual rate of infection, the lifetime risk of infection was calculated
assuming that workers are exposed for 45 years and that the worker's exposure
profile and working conditions remain constant throughout his or her working
lifetime. Lifetime infection rates are then used to calculate the lifetime
risk of developing active disease based on the estimate that 10 % of all
infections result in active disease. Given a number of active cases of TB,
the number of expected deaths can be calculated based on the estimated
average TB case death rate (i.e., number of TB deaths per number of active TB
cases averaged over 3 years as reported by CDC). OSHA
estimates that the risk of material impairment of health or functional
capacity, that is, the average lifetime occupational risk of TB infection for
hospital workers ranges from 30 to 386 infections per 1,000 workers who are
occupationally exposed to TB. These are different national averages, each
derived by calculating the risk in each state and weighting it by the state's
population. The low end of this range is derived by using the Washington
State data, and is likely to seriously underestimate the true risk to which
workers are exposed. This is because the Washington data represent
occupational exposures among employees in hospitals which are located in
areas of the country with a low prevalence of active TB and which have
implemented TB controls (e.g., early identification procedures, annual
skin testing, and negative pressure in AFB isolation rooms). The high end of
this range is derived by using the Jackson Memorial Hospital study, and
represents occupational risk for workers in hospitals located in high TB
prevalence areas, serving high risk patients, and with a high frequency of
exposure to infectious TB. OSHA
also used information from the Washington State database to estimate national
average estimates of lifetime risk for workers in long-term care (i.e.,
nursing homes), home health care, and home care. The national average
lifetime risk of TB infection is estimated to be 448 per 1,000 for workers in
long-term care facilities, 225 per 1,000 for workers in home health care
(primarily nursing staff), and 69 per 1,000 for workers in home care. The
higher likelihood of occupational exposure in long-term care facilities
(early identification of suspect TB cases is often difficult among the
elderly) and the presence of fewer engineering controls in these facilities
may explain the high observed occupational risk in that work setting. The
national average lifetime risk of developing active disease ranges from
approximately 3 to 39 cases per 1,000 exposed employees for workers in
hospital settings. Similarly, the average lifetime risk of active disease is
estimated to be approximately 45 per 1,000 for workers in long-term care, 26
per 1,000 in home health care, and 7 per 1,000 in home care. This range is
based on the estimate that 10 % of infections will progress to active disease
over one's lifetime. This risk may be greater for immunocompromised
individuals. The
national average lifetime risk of death from TB ranges from 0.2 to
approximately 3 deaths per 1,000 exposed employees for workers in hospital
settings. Similarly, the average lifetime risk of death from TB is estimated
to be approximately 3.5 per 1,000 for workers in long-term care, 2 per 1,000
for workers in home health care, and 0.5 per 1,000 in home care. The lower
range of the national lifetime risk of deaths, 0.2 per 1,000, is based on the
Washington State hospital data where the prevalence of TB is low and
infection control measures have been implemented. Thus, this lower range of
risk underestimates the risk of death from TB for other employees who work in
settings where infection control measures, such as those outlined in this
proposed standard, have not been implemented. The risk assessment data show
that where infection control measures were not in place, the estimated risk
of death from TB was as high as 6 deaths per 1,000 exposed employees. The
quantitative risk estimates are based primarily upon data from hospitals and
selected other work settings. However, it is frequent exposure to aerosolized
M. tuberculosis which places workers at substantially increased risk of
infection and not factors unique to the health care profession or any job
category therein. Qualitative evidence, such as that from the epidemiological
studies, case reports and outbreak investigations reported for various types
of work settings, as discussed earlier in the Health Effects section, clearly
demonstrates that employees exposed to aerosolized M. tuberculosis
have become infected with TB and have gone on to develop active disease. These
work settings share risk factors that place employees at risk of
transmission. For example, these work settings serve client populations that
are composed of a high prevalence of individuals who are infected with TB,
are immunocompromised, are injecting drug users or are medically underserved
and of poor general health status. Therefore, there is an increased
likelihood that employees in these work settings will encounter individuals
with active TB. In addition, high-hazard procedures, such as bronchoscopies,
are performed in some of these work settings, which greatly increases the
likelihood of generating aerosolized M. tuberculosis. Moreover, some
of the work settings have environmental conditions such as overcrowding and
poor ventilation, factors that facilitate the transmission of disease. Therefore,
OSHA believes that the quantitative risk estimates based on hospital data and
other selected health care settings can be extrapolated to other occupational
settings where there is a similar increased likelihood of exposure to
aerosolized M. tuberculosis. Having
specific data for non-<<health care workers>> and workplace conditions would
add more precision to the quantitative risk assessment, but that level of
detail is not possible with the currently available information. However, the
Agency believes that such a level of detail is not necessary to make its
findings of significant risk because the risk of infection is based upon
occupational exposure to aerosolized M. tuberculosis. Nevertheless,
OSHA seeks information on conversion rates and the incidence of active
disease among employees in non-health care work settings in order to give
more precision to its estimates of risk. OSHA's
risk estimates for TB infection are comparable to other risks which OSHA has
concluded are significant, and are substantially higher than the example
presented by the Supreme Court in the Benzene Decision. After considering the
magnitude of the risk as shown by the quantitative and qualitative data, OSHA
preliminarily concludes that the risk of material impairment of health from
TB infection is significant. OSHA
also preliminarily concludes that the proposed standard for occupational
exposure to TB will result in a substantial reduction in that significant
risk. The risk of infection is most efficiently reduced by implementing TB
exposure control programs for the early identification and isolation of
individuals with suspected or confirmed infectious TB. Engineering controls
to maintain negative pressure in isolation rooms or areas where infectious
individuals are being isolated will reduce the airborne spread of aerosolized
M. tuberculosis and subsequent exposure of individuals, substantially
reducing the risk of infection. In addition, for those employees who must
enter isolation rooms or provide services to individuals with infectious TB,
respiratory protection will reduce exposure to aerosolized M. tuberculosis
and thus reduce the risk of infection. Several
studies have shown that the implementation of infection control measures such
as those outlined in this proposed standard have resulted in a reduction in
the number of skin test conversions among employees with occupational
exposure to TB. For example, results of a survey conducted by the Society of
Healthcare Epidemiology of America (SHEA) of its member hospitals (Exs. 7-147
and 7-148) revealed that among hospitals that treated 6 or more patients with
infectious TB per year there were 68 % fewer tuberculin skin test conversions
in hospitals that had AFB isolation rooms with one patient per room, negative
pressure, exhaust air directed outside and six or more air changes per hour,
compared to hospitals that did not have AFB isolation rooms with these same
characteristics. Similarly, an 88 % reduction in tuberculin skin test
conversions was observed in an Atlanta hospital after the implementation of
infection control measures such as an expanded respiratory isolation policy,
improved diagnostic and testing procedures, the hiring of an infection
control coordinator, expanded education of <<health care workers>>, increased frequency of
tuberculin skin tests, implementation of negative pressure, and use of
submicron masks for <<health care workers>> entering isolation rooms (Ex.
7-173). Improvements in infection control measures in a Florida hospital
after an outbreak of MDR-TB reduced tuberculin skin test conversions from 28
% to 18 % to 0 % over three years (Ex. 7-167). These improvements included
improved early identification procedures, restriction of high-hazard
procedures to AFB isolation rooms, increased skin testing, expansion of
initial TB treatment regimens, and daily inspection of negative pressure in
AFB isolation rooms. Thus, these investigations show that the implementation
of infection control measures such as those included under OSHA's proposed
standard for TB can result in substantial reductions in infections among
exposed employees. As
discussed in further detail in the following section of the Preamble to this
proposed standard, OSHA estimates that full implementation of the proposed
standard for TB will result in avoiding approximately 21,400 to 25,800
work-related infections per year, 1,500 to 1,700 active cases of TB resulting
from these infections and 115 to 136 deaths resulting from these active
cases. In addition, because the proposed standard encourages the
identification and isolation of active TB cases in the client populations
served by workers in the affected industries, there will also be
non-occupational TB infections that will be averted. OSHA estimates that
implementation of the proposed standard will result in avoiding approximately
3,000 to 7,000 non-occupational TB infections, 300 to 700 active cases of TB
resulting from these infections, and 23 to 54 deaths resulting from these
active cases. OSHA preliminarily concludes that the proposed standard for TB
will significantly reduce the risk of infection, active disease and death
from exposure to TB and that the Agency is thus carrying out the
Congressional intent and is not attempting to reduce insignificant risks. Although
the current OSHA enforcement program, which is based on the General Duty
Clause of the Act, Section 5(a)(1), and the application of some general
industry standards, such as 29 CFR 1910.134, Respiratory Protection, has
reduced the risks of occupational exposure to tuberculosis to some extent,
significant risks remain and it is the Agency's opinion that an occupational
health standard promulgated under section 6(b) of the Act will much more
effectively reduce these risks for the following reasons. First, because of
the standard's specificity, employers and employees are given more guidance
in reducing exposure to tuberculosis. Second, it is well known that a
standard is more protective of employee health than an enforcement program
based upon the general duty clause and general standards. Unlike the proposed
standard, the general duty clause specifies no abatement methods and the
general industry standards do not set forth abatement methods specifically
addressing occupational exposure to TB. Third, the general duty clause
imposes heavy litigation burdens on OSHA because the Agency must prove that a
hazard exists at a particular workplace and that it is recognized by the
industry or the cited employer. Since the proposed standard specifies both
the conditions that trigger the application of the standard and the
employer's abatement obligations, thereby establishing the existence of the
hazard, no independent proof that the hazard exists in the particular
workplace need be presented. The reduction in litigation burdens will mean
that the Labor Department, as well as the employer, will save time and money
in the investigation and litigation of occupational TB cases. Finally, the
promulgation of this proposed standard will result in increased protection
for employees in state-plan states which, although not required to adopt
general duty clauses, must adopt standards at least as effective as Federal
OSHA standard. In
summary, the institution of the enforcement guidelines has been fruitful, but
it has not eliminated significant risks among occupationally exposed
employees. Therefore, OSHA preliminarily concludes that a standard
specifically addressing the risks of tuberculosis is necessary to further
substantially reduce significant risk. OSHA's preliminary economic analysis
and regulatory flexibility analysis indicate that the proposed standard is
both technologically and economically feasible. OSHA's analysis of the
technological and economic feasibility is discussed in the following section
of the preamble. VII. Summary of the Preliminary Economic Analysis and Regulatory
Flexibility Analysis OSHA
is required by the Occupational Safety and Health Act of 1970 and several
court cases pertaining to that Act to ensure that its rules are
technologically and economically feasible for firms in the affected
industries. Executive Order (EO) 12866 and the Regulatory Flexibility Act (as
amended) also require Federal agencies to estimate the costs, assess the
benefits, and analyze the impacts on the regulated community of the
regulations they propose. The EO additionally requires agencies to explain
the need for the rule and examine regulatory and non-regulatory alternatives
that might achieve the objectives of the rule. The Regulatory Flexibility Act
requires agencies to determine whether the proposed rule will have a
significant economic impact on a substantial number of small entities,
including small businesses and small government entities and jurisdictions. For
proposed rules with such impacts, the agency must prepare an Initial
Regulatory Flexibility Analysis that identifies those impacts and evaluates
alternatives that will minimize such impacts on small entities. OSHA finds
that the proposed rule is "significant" under Executive Order 12866
and "major" under Section 804(2) of the Small Business Regulatory
Enforcement Fairness Act of 1996. Accordingly, the Occupational Safety and
Health Administration (OSHA) has prepared this Preliminary Economic and
Regulatory Flexibility Analysis (PERFA) to support the Agency's proposed
standard for occupational exposure to tuberculosis (TB). The following is an
executive summary of that analysis. The entire test of the PERFA can be found
in the rulemaking docket as Exhibit 13. The complete PERFA is composed of
various chapters that describe in detail the information summarized in the
following section. Statement of Need TB
is a communicable, potentially lethal disease caused by the inhalation of
droplet nuclei containing the bacillus Mycobacterium tuberculosis (
M. tuberculosis). Persons exposed to these bacteria can respond in
different ways: by overcoming the challenge without developing TB, by
becoming infected with TB, or by developing active TB disease. Those who
become infected harbor the infection for life, and have a 10 percent chance
of having their infection progress to active disease at some point in their
life. Those with active disease have the signs and symptoms of TB (e.g.,
prolonged, productive cough; fatigue; night sweats; weight loss) and have
about an 8 percent risk of dying from their disease. TB
has been a worldwide health problem for centuries, causing millions of deaths
worldwide. In the United States, however, there has been a decline in the
number of active TB cases over the last four decades. Between 1953 and 1994,
the number of active cases declined from 83,304 to 24,361, an annual rate of
decline of 3.6 percent over the period as a whole (Figure VII-1). The
1988-1992 period, however, saw the first substantial increase in the number
of active cases since 1953. A number of outbreaks of this disease have
occurred among workers in health care settings, as well as other work
settings, in recent years. To add to the seriousness of the problem, some of
these outbreaks have involved the transmission of multi-drug resistant
strains of M. tuberculosis, which are often fatal. Very recently,
i.e., after 1992, this trend has reversed, and the number of such cases
appears once again to have begun to decline. Nevertheless, TB remains a major
health problem, with 22,813 active cases reported in 1995. Because active TB
is endemic in many U.S. populations -- including groups in both urban and
rural areas -- workers who come into contact with diseased individuals are at
risk of contracting the disease themselves. Many
occupational groups, including workers in health care, nursing homes,
homeless shelters, hospices, correctional facilities, laboratories,
physicians' offices, and other settings are at risk of contracting TB on the
job. These workers are at risk because they are exposed in the course of
their work to patients and others with active TB disease, perform procedures
that expose them to airborne concentrations of M. tuberculosis, or
serve client populations where the incidence of active disease is unusually
high. The
purpose of OSHA's standard is to reduce these risks in health care and other
work settings where active TB cases are likely to be encountered by
employees. To accomplish this goal, the proposed standard requires those
employers who are responsible for the working conditions where such
encounters occur to implement a program of infection prevention and infection
control that is designed to prevent occupational infections in the first
place, and to identify and treat any job-related infections that do occur. The
approach taken in the proposed standard is similar to that adopted by OSHA in
its 1991 bloodborne pathogens standard, which is given credit for achieving a
dramatic reduction in the number of cases of hepatitis among health care and
other workers since it was issued. OSHA predicts that, once implemented, the
proposed TB standard will have similar results, achieving reductions on the
order of 70 to 90 percent in the number of TB infections, active cases, and
directly related deaths. This
Preliminary Economic and Regulatory Flexibility Analysis includes an
introductory chapter that describes the major provisions of the standard. The
proposal would apply to occupational exposure to TB occurring in, during, or
through the provision of services by:
The
groups, industries, and work settings covered by the standard have been
included in its scope for specific reasons. For example, hospitals are
included because they treat patients with active TB disease, while hospices,
certain laboratories, pulmonary and certain other physicians, medical
examiners, and contract HVAC workers are covered because employees in these
settings/jobs are exposed to aerosolized M. tuberculosis during the
performance of high-hazard procedures, such as bronchoscopies, sputum
induction, autopsies, and during work on ventilation systems that may contain
TB bacteria. Other work settings, such as homeless shelters and nursing
homes, are covered because their employees serve a client population known to
have a high incidence of TB infection. Another group of employees included
within the scope of the standard are workers who must occasionally serve
patients with active TB who are being treated in "isolation," i.e.,
a room or area specifically designed to contain the TB microorganism and
prevent its spread to surrounding areas. Attorneys and social workers are
typical of this group. Finally, the proposed standard covers personnel
service agencies that provide temporary, seasonal, or "leased"
personnel to hospitals and other covered work settings. OSHA
estimates that the standard would apply to approximately 102,000
establishments and provide protection to more than 5 million workers
currently at risk of occupational exposure to TB. More than half of these
workers -- almost 4 million -- work in the two industries most affected by
the standard: hospitals and nursing homes. Other covered industries with
large numbers of workers are home health care, emergency medical services,
and correctional institutions. Table
VII-1 shows the number of affected establishments and the population at risk
for each covered industry. (Table VII-1 does not include all sectors that
might hypothetically be covered by the standard. For example, a chiropractor
who engaged in high hazard procedures would be covered by the standard. However,
this possibility is sufficiently rare for this activity not to have been
included in this analysis. OSHA solicits comments on any affected job
categories or industries it may have omitted.) Because the standard requires
employers in the covered industries to make an initial determination that
will identify which job classifications, employees, and activities within
their workplace involve occupational exposure to TB, its requirements are
narrowly targeted to those workers most at risk. Thus, for example, only
approximately 57 percent of hospital workers are potentially affected by the
standard; these workers would include those working on infectious disease
floors or wards, radiology units, autopsy suites, and in other, similarly
exposed locations. Technological Feasibility Chapter
III of the analysis evaluates the technological feasibility of the proposed
standard for affected establishments. OSHA preliminarily concludes that no
provisions of the rule pose technological feasibility problems for any
potentially affected entities. This is the case because the standard emphasizes
administrative controls, such as the early identification of suspected or
confirmed cases of TB and employee information and training, rather than
engineering controls. In addition, the engineering controls that are
required, such as AFB isolation rooms, biological safety cabinets, and
temporary AFB isolation facilities, would be mandated only in those
situations where individuals with suspected or confirmed infectious TB are
admitted and isolated, where high hazard procedures are performed, and in situations
where individuals cannot be placed into AFB isolation rooms within five hours
of being identified as having suspected or confirmed infectious TB. All of
the engineering controls required by the standard are currently available and
in widespread use in many affected establishments. Benefits of the Proposed Standard Workers
employed in the work settings covered by the standard are at significant risk
of material impairment of health as a result of exposure to M.
tuberculosis on the job. These workers will be the primary beneficiaries
of the protection provided by the rule. However, because TB is a communicable
disease, many other individuals will also benefit from the standard. Reducing
the number of cases of TB among workers who are regularly in contact both
with patients and infected members of client populations will reduce the
incidence of TB infections and active cases in these client populations
(since infected individuals spend the most time with other members of their
group) and among members of the families of exposed workers. OSHA has
expressed the benefits of the standard in terms of the numbers of TB
infections, active cases, and TB-related deaths averted by the standard. In
addition to reducing morbidity and mortality among workers, their families,
and client populations, the standard will also generate readily quantifiable
cost savings in the form of lower medical costs, less lost production, and
reduced costs for administering workers' compensation claims and other
private and social insurance system transactions. OSHA's
estimates of the potential benefits of the standard take into account the
extent of current industry compliance with the provisions of the proposed
standard, i.e., the benefits estimates do not include the benefits that employers
in affected sectors are already garnering as a result of their voluntary
efforts to provide protections to their TB-exposed employees. The benefits
assessment presented in Chapter IV of the economic analysis is based on
OSHA's Preliminary Risk Assessment (see that section of the preamble), which
quantifies the occupational risk of TB infection among workers in hospitals,
nursing homes, home health care work settings, and home care work settings. The
estimates of risk are based on the rate of tuberculin skin test (TST)
conversions among these populations. TST conversions are a widely used and
well-documented index of TB infection; rates of conversion among the exposed
populations are then compared with rates in unexposed or less-exposed
"control" populations to obtain an estimate of the
"excess" risk associated with occupational exposure. Table VII-2
shows the results of OSHA's estimates of the risks confronting workers in
various work settings, based on statistical analyses and studies in the
literature. Where
risk data of good quality were available for a specific industry, OSHA relied
on that data. However, such data were available only for the hospital,
nursing home, home health care, and home care industries. Accordingly, OSHA
identified the best data to use to characterize the occupational risk of TB
infection posed to workers in the other work settings covered by the proposed
rule. After a careful review of the available data, OSHA chose to rely on
data from western North Carolina that looked at occupational risk in a total
of eight hospitals. These data were selected because they derived from
hospitals that were relatively "uncontrolled," i.e., that had not
yet implemented many of the controls that would be required by the proposed
standard. Data from the other hospitals shown in Table VII-2 were judged to
be less appropriate for the purpose of extrapolation because Washington State
hospitals are already generally in compliance with the requirements of the
proposed rule and Jackson Memorial Hospital had recently experienced an
outbreak of multi-drug resistant TB among its patients at the time the risk
data were gathered. OSHA believes that using occupational risk data from
hospitals to characterize the risk in other occupational settings for which
risk data are unavailable is appropriate because employees in these other
settings serve client populations that have a high incidence of active TB
cases, perform high-hazard procedures, or visit hospitalized TB patients. The
use of a hospital-based risk estimate results in a lower estimate of risk
than would be the case if OSHA had used risk data from nursing homes or home
health care to characterize the risk in other settings, but a higher risk
than if OSHA had used risk data from the home care industry to do so. To
predict the effectiveness of the proposed standard, OSHA evaluated the
reduction in occupational risk that various control measures required by the
standard can be expected to achieve. Effectiveness is measured as the percent
reduction in TST conversions and in the TB infections, active cases, and
deaths represented by those conversions. Based on a thorough review of the
available literature on the effectiveness of control programs that have actually
been implemented in a number of hospitals, OSHA believes that the proposed
standard, once implemented, would reduce TB infections among occupationally
exposed hospital workers by 90 percent, and would decrease such infections in
the other work settings covered by the standard by 70 to 90 percent. OSHA
also estimated the effectiveness and medical surveillance and follow-up in
preventing infections from advancing to active cases of TB. OSHA found that
such measures reduced the probability of an infection advancing to an active
case by 35 to 47 percent, depending on the frequency of testing. Using
these effectiveness data, taking account of the current levels of compliance
in various workplaces, and relying on the estimates of excess risk presented
in OSHA's Preliminary Risk Assessment, OSHA predicts that the proposed
standard will avert about 21,000 to 26,000 work-related TB infections per
year, 1,500 to 1,750 active disease cases resulting directly from these
infections, and 115 to 136 deaths directly related to the same infections. Preventing
this number of infections among workers will, in turn, prevent about 3,000 to
7,000 infections, 300 to 700 active cases, and 23 to 54 deaths among the
families, friends, clients, and contacts of these workers. In addition, the
standard will annually generate cost savings of $89 to $116 million dollars
in avoided medical costs, lost production caused by absence from work and
other factors, and insurance administration costs. Table VII-3 shows the
benefits of the proposed standard. Chapter
V of the economic analysis projects the costs employers in the various
industries covered by the standard are estimated to incur to achieve
compliance with the rule's requirements. OSHA estimated costs for each
covered industry and for each provision of the standard. These costs take
account of the baseline levels of compliance prevailing in each industry at
the present time and are presented as annualized costs discounted at 7 percent.
Annualized costs are the sum of annualized initial costs and recurring annual
costs. For example, a temporary AFB isolation room costing $4,095 with annual
maintenance costs of $50 would have annualized costs of $633 ($583 + $50). The
total estimated costs of compliance for the standard as a whole are $245
million per year. The most costly provisions of the standard are those
requiring medical surveillance and training for occupationally exposed
employees. Together, these two provisions account for 60 percent of the costs
of compliance. The two industries projected to incur the highest costs are
hospitals and nursing homes. Together, the costs incurred by these two
industries are estimated to be $138 million per year. Tables VII-4 and VII-5
summarize the annualized costs of compliance, by provision and industry,
respectively. Chapter
VI assesses the economic impacts of the proposed standard on the industries
affected by the proposed standard and also analyzes the impacts on the small
businesses within each of these industries. OSHA preliminarily concludes that
the standard is economically feasible for affected firms. On average,
annualized compliance costs for all entities amount only to 0.06 percent of
revenues and only 1.8 percent of profits. For all industries, costs as a
percentage of revenues are less than 1 percent. For two industries, costs as
a percentage of profits exceed 5 percent; these industries are substance
abuse treatment centers and personnel services. OSHA does not believe,
however, that these profit impacts will actually be incurred by facilities in
these two sectors. Only 18.5 percent of substance abuse treatment centers
operate on a for-profit basis. If substance abuse treatment centers can
increase their revenues by as little as 0.34 percent, they can completely
offset their compliance costs. The revenue increases or reductions in
services needed to achieve cost passthrough are not expected to represent
significant impacts for these facilities. The situation for personnel service
firms is similar; these firms would have to increase the prices charged to
their customers by as little as 0.56 percent to completely offset the costs of
compliance. It is likely that these agencies will be able to pass such a
small increase in costs through to their customers, i.e., to facilities
purchasing personnel services. Table VII-6 shows compliance costs as a
percentage of revenues, by industry. OSHA
has preliminarily concluded that the proposed standard will have a
significant impact on a substantial number of small entities and has
therefore, as required by the Regulatory Flexibility Act Amendments of 1996,
conducted an Initial Regulatory Flexibility Analysis (IRFA). This analysis
has identified significant impacts on the small entity portion of the
hospital, nursing home, correctional institution, homeless shelter, substance
abuse treatment center, contract HVAC, and personnel services industries. For
the purposes of this analysis, OSHA defines small for-profit entities using
the Small Business Administration's (SBA's) Table of Size Standards. For
businesses affected by the proposed standard, the SBA classifies entities
with annual revenues of less than $5 million as small for all industries,
with the exception of contract HVAC firms, for which entities with less than
$7 million in annual revenues are classified as small. A
small not-for-profit entity is defined as any nonprofit enterprise that is
independently owned and operated and is not dominant in its field. Based on
this definition, all not-for-profit entities affected by the proposed
standard are considered small. Many
of the affected industries consist almost entirely of public sector
facilities, such as correctional facilities, immigration detainment
facilities, law enforcement facilities, medical examiners' offices, and
social service organizations. Several other affected industries include some
government-owned facilities, such as hospitals, nursing homes, and emergency
medical services. Under the Regulatory Flexibility Act, "small
governmental jurisdiction" refers to governments of cities, counties,
towns, townships, villages, school districts, or special districts with
populations of less than 50,000. For most of the affected industries,
information on the number of such entities was not readily available. Where
data were unavailable, the number of small publicly-owned entities was estimated
based on the average number of people served per employee in each industry,
from which OSHA estimated the average employment size of establishments
serving populations of less than 50,000. These entities are considered small
for the purposes of this analysis. OSHA requests information on size
standards for public-sector entities. OSHA
requests comment on these definitions and estimates of the number of small
entities. The complete IRFA is presented in Chapter VI of the economic
analysis, and is also presented here. Initial Regulatory Flexibility Analysis The
Regulatory Flexibility Act, as amended in 1996, requires that an Initial
Regulatory Flexibility Analysis contain the following elements: (1)
A description of the reasons why action by the agency is being considered; (2)
A succinct statement of the objectives of, and legal basis for, the proposed
rule; (3)
A description of, and, where feasible, an estimate of the number of small
entities to which the proposed rule will apply; (4)
A description of the projected reporting, recordkeeping and other compliance
requirements of the proposed rule, including an estimate of the classes of
small entities that will be subject to the requirement and the type of
professional skills necessary for preparation of the report or record; and (5)
An identification, to the extent practicable, of all relevant Federal rules
that may duplicate, overlap or conflict with the proposed rule. In
addition, a regulatory flexibility analysis must contain a description of any
significant alternatives to the proposed rule that accomplish the stated
objectives of applicable statutes (in this case the OSH Act) and that
minimize any significant economic impact of the proposed rule on small
entities.(3) This section of the analysis closes
with a review of the recommendations of the SBREFA Panel concerning this
proposed rule and discusses how OSHA has responded to these recommendations. Reasons for the Proposed Rule From
1985 to 1994, the number of active TB cases in the United States increased by
9.4 percent, reversing a 30-year downward trend. Although the number of cases
reported to the CDC has declined over the past few years, TB remains a
serious problem in the United States. In 1994, 24,361 active TB cases were
reported to the Centers for Disease Control and Prevention (CDC), and TB was
reported to have caused 1,590 deaths in that year alone (Ex. 7-283). Transmission
of M. tuberculosis is a recognized risk in several work settings. A
number of outbreaks of this dreaded disease have occurred among workers in
health care settings, as well as other work settings, in recent years. To add
to the seriousness of the problem, some of these outbreaks have involved the
transmission of multidrug-resistant strains of M. tuberculosis, a form
of the disease that is often fatal. Objectives of the Proposed Rule The
objective of this proposal is to reduce the risk of occupational exposure to M.
tuberculosis in exposed working populations through the use of
engineering controls, work practice controls, respiratory protection, medical
surveillance, training, signs and labels, and recordkeeping. Implementation
of these measures has been shown to minimize or eliminate occupational
exposure to M. tuberculosis, and thus to reduce the risk of TB
infection among workers. The legal authority for this proposed standard is
the Occupational Safety and Health Act, 29 U.S.C. 655(b). Description of the Number of Small Entities The
proposed rule would cover 80,400 establishments operated by 67,116 small
entities, as defined above. Of the 67,116 small entities, about 49 percent
(32,605 entities) are for-profit small entities, 20 percent (13,622 entities)
are publicly-owned, and 31 percent (20,889 entities) are not-for-profit. About
79 percent of the total number of affected establishments are operated by
small entities. The proposed rule covers 48,804 establishments operated by
48,044 very small entities, defined as entities of all kinds employing fewer
than 20 workers. Almost 48 percent of the affected establishments are
operated by very small entities. Description of Proposed Reporting, Recordkeeping and Other Compliance
Requirements Avoiding a One-Size-Fits-All Standard. Occupational TB occurs in a wide variety of
settings, which means that the risk varies substantially, and control
measures differ, from one facility to another. OSHA's proposed TB standard
has been tailored to recognize these differences. With respect to the
background risk of exposure, the OSHA standard distinguishes between work
settings in counties that have had no cases of TB in one of the past two
years and fewer than 6 cases in the other of the past two years, work
settings in counties with one or more cases of TB in both of the past two
years or that have had 6 or more cases of TB in one of the past two years,
and work settings that have encountered 6 or more cases of TB in the past 12
months. In addition, the OSHA standard treats different types of exposure to
TB differently. For example, the standard has different requirements for
employers who own facilities that treat TB patients, employers whose client
populations have high TB rates, employers whose employees (such as attorneys
and social service providers) visit patients who have been identified as
having suspected or confirmed cases of TB, employers whose employees engage
in various high hazard procedures, employers whose employees provide
maintenance for ventilation systems serving confirmed or suspected TB
patients, and employers who provide personnel to treat patients in their own
homes. In part because of these many distinctions, the SBREFA Panel found
that the regulation was difficult for many employers to understand (Ex. 12). To
make the tailoring of the standard to specific situations easier to see, OSHA
has developed tables showing which provisions of the standard are most likely
to apply to employers in different circumstances and in various affected
sectors (see the Scope paragraph discussion in Section X of the Preamble,
"Summary and Explanation"). In addition, OSHA intends to provide
extensive outreach when the standard is published in final form. OSHA
solicits comments on other ways to avoid a "one-size-fits-all"
standard while at the same time making the standard easier to follow. For
example, would developing a flow chart and/or expert system that asks
employers a series of questions and then directs employers to applicable
requirements be an aid to affected small entities? Description of the Proposed Standard. The proposed rule would require that
employers develop and implement exposure control plans; institute work
practice and engineering controls; provide respiratory protection in various
situations; provide medical surveillance (e.g., tuberculin skin
testing, medical histories, medical management, medical follow-up, medical
removal); and communicate hazards through the use of signs, labels, and
training. These proposed requirements are discussed in greater detail in the Introduction
(Chapter I) of this analysis. The
proposed standard would also require that employers establish and maintain
medical, training, illness/injury, and engineering control maintenance and
performance monitoring records. All establishments affected by the proposed
rule would be affected by these proposed requirements. However, only
establishments with engineering controls would be required to maintain
records of the maintenance and monitoring of engineering controls. In
estimating the cost of establishing and maintaining medical records, OSHA
used the wage rate of a clerical worker with some knowledge of medical
recordkeeping as the base wage. However, the knowledge required to perform
such duties can be acquired by most clerical workers with little effort. All
recordkeeping requirements included in the proposed rule could therefore be
performed by the existing staff in any of the covered industries. A detailed
description of the proposed requirements appears in the Introduction and in
the Costs of Compliance chapters of this analysis. Relevant Federal Rules That May Duplicate, Overlap, or Conflict With
the Proposed Rule On
October 28, 1994, the Centers for Disease Control and Prevention (CDC) of the
U.S. Department of Health and Human Services published "Guidelines for
Preventing the Transmission of Mycobacterium tuberculosis in
Health-Care Facilities," which recommends that facilities adopt many of
the requirements included in this proposed standard. CDC has also published
guidelines for the prevention of transmission of TB in homeless shelters,
long-term care facilities for the elderly, and correctional institutions. OSHA
has consulted with CDC in developing the proposed standard, and the basic
elements of the standard correspond to the basic elements in the CDC
guidelines. However, the CDC publication is only recommendatory and is
therefore not enforceable. OSHA's studies (see chapters IV and V) show that
few facilities are following all elements of these guidelines. Further, many
portions of the CDC guidelines are written in language that does not lend
itself to enforcement even if the guidelines were made mandatory. For
example, portions of the CDC guidelines for health care facilities suggest
that the employer "consider" adopting certain controls. A fuller
discussion of the similarities and differences between OSHA's proposed rule
and the CDC's recommendations is provided in Section III of the Preamble,
which describes the events leading to the proposed standard. Although the
U.S. Public Health Service has overall responsibility for the control of TB
in the U.S. population, OSHA is the only agency specifically mandated to
address the problem of TB transmission in occupational settings. The
Health Care Financing Administration (HCFA) of the U.S. Department of Health
and Human Services requires that facilities undergo an initial accreditation
inspection prior to receiving Medicare and Medicaid funding. Such facilities
include hospitals, nursing homes and other long-term care facilities, and
clinical laboratories. Hospitals are reinspected annually, nursing homes
every 15 months, and laboratories every two years. One of the requirements of
such accreditation is the implementation of an infection control program. However,
unlike the OSHA proposed rule, HCFA's requirements do not specify the
elements that must be included in such a program. HCFA may cite facilities
with poor results for specific program deficiencies but does not have the
authority to cite facilities for failing to include specific elements in
their infection control programs, unless those program elements are
specifically required by an OSHA standard. This means that in the absence of
an OSHA TB standard, HCFA could not require implementation of specific
controls. The proposed rule does not in any way conflict with HCFA
requirements. Further, the existing HCFA requirements have not ensured that
health care facilities adopt the elements of an effective infection control
and have not prevented outbreaks of TB in this workforce. One
small entity representative to the SBREFA Panel suggested that the OSHA
regulation might conflict with state and local requirements for skin testing
and for tracing contacts of active cases of TB (Ex. 12). OSHA has considered
this suggestion and believes there is no conflict. Some states do have rules
covering TB testing and contact tracing, but most states do not. In 1993,
only 18 states had requirements for TB screening of employees in medical
facilities, and only 23 states had testing requirements for nursing home employees.
Further, these requirements are sometimes not as stringent as those OSHA is
proposing; for example, some states require only an initial skin test. Although
49 states require the investigation of reported cases of TB, only 29 states
require contact tracing by health departments. In states where local health
departments provide contact tracing, such contact tracing would constitute
compliance with OSHA's requirements for contact tracing by employers. Employers
merely need to assure that contact tracing takes place; they need not do the
contact tracing themselves if others are available to do this job for them. Thus,
there is no conflict between the OSHA standard and existing state
requirements, nor do existing state laws obviate the need for a standard that
requires TB testing of exposed employees and the investigation of reported TB
exposures. However, OSHA solicits comment on the interaction of state rules
regarding testing and tracing and the proposed standard. One
small entity representative was concerned with how medical removal protection
and worker compensation programs would interact (Ex. 12). Medical removal
protection requires that workers receive full salaries, full benefits, and no
loss of job position or seniority while the employee is unable to work, or
unable to work at his/her usual position, as a result of incurring an
occupational case of TB. The purpose of medical removal protection is to
assure that workers provide timely and accurate information to their
employers concerning their medical symptoms. In the absence of medical
removal protection, workers have financial and job security incentives to
avoid reporting symptoms. OSHA counts any payments workers receive from
workers' compensation toward the goal of assuring medical removal protection;
that is, employers may deduct from the amount they pay out to the worker any
monies paid to the ill worker by workers' compensation. Workers' compensation
is not an adequate substitute for medical removal protection because workers'
compensation does not fully replace lost wages and provides no guarantee of
maintenance of seniority, job security, current position, or non-wage
benefits. Medical removal protection requires the employer to provide any of
these elements that are not a part of workers' compensation. Thus, the
employer of a worker already receiving workers' compensation would need to
provide an additional salary increment in order to restore the employee's
full salary and would need to provide the worker his or her full non-wage
benefits. One
small entity representative expressed concern over a possible conflict
between the proposed rule and Federal Confidentiality Regulations covering
chemically abusive or dependent clients participating in licensed and
federally-funded programs [Ex. 12]. These regulations prohibit disclosing
information regarding the identification of a patient as a substance abuser
without the patient's consent. This representative noted that, without
patient consent, a disclosure may be made only to medical personnel to meet a
situation that has been declared a medical emergency by the Surgeon General. This
small entity representative was referring to Public Health regulations:
Confidentiality of Alcohol and Drug Abuse Patient Records, 42 CFR 2, and a
similar state statute: Confidentiality of Records, Minnesota Statute 254A.09.
Both the Federal Confidentiality Regulations and the state statute cover
records that would identify a patient as an alcoholic or drug abuser or
concern his or her prognosis, diagnosis, treatment, attendance, status or
physical whereabouts. No requirements of the standard would require the
disclosure of records of this kind. These are not the kinds of records that
are relevant to determining whether an individual has suspect or confirmed
infectious TB. In addition, a medical referral for the client who is
exhibiting signs and symptoms of TB can be made without revealing any of the
prohibited confidential information. Moreover, in the case of an exposure
incident, the identity of the individual with suspected or confirmed
infectious TB need not be told to employees. Records maintained by employers
on their employees are not covered by the regulations or statute, but would
be subject to the same confidentiality requirements that govern all medical
records. The identification and notification requirements in the proposed TB
standard are the minimum necessary to prevent transmission of TB to
employees. The contagious nature of the disease mandates early detection and
early monitoring of individuals who have had an exposure incident. One
small entity representative to the SBREFA Panel expressed concern over
possible interactions between the proposed standard and the Family and
Medical Leave Act (FMLA) (Ex. 12). The Family and Medical Leave Act does not
provide for leave with pay, and does not guarantee the continuation of any
benefits other than health insurance. Further, the Family and Medical Leave
Act covers a more limited timeframe (12 weeks) than the proposed standard's
medical removal protection provisions (18 months). Thus, the only overlap
between the proposed standard and the FMLA would occur in the area of health
insurance benefits in the first 12 weeks of the worker's absence from work. Since
the standard would specifically allow the employer to deduct from medical
removal protection benefits any benefits paid to the worker from other
sources, employers would not pay for the same benefits twice. One
small entity representative felt that the Americans with Disabilities Act
(ADA) may offer protection to the "worker who becomes ill as a result of
an occupational exposure or who cannot work because of an inability to wear a
PR [respirator]." (Ex. 12) The ADA prohibits employers of 15 or more
employees from discriminating, because of the disability, against a qualified
individual with a disability with regard to terms, conditions and privileges
of employment. An employer must provide reasonable accommodation for known
physical or mental limitations for a qualified individual with a disability,
unless accommodation can be shown to impose undue hardship on the employer. OSHA
representatives noted that there is no conflict between an OSHA standard and
the ADA requirements prohibiting discrimination. The ADA says that: Nothing
in this Act shall be construed to invalidate or limit the remedies, rights
and procedures of any Federal law * * * that provides greater or equal
protection for the rights of individuals with disabilities that are afforded
by this Act. 42 U.S.C.A. 12201(b). Further,
the ADA would not provide the same protections as medical removal protection.
In order for an employee to take advantage of the provisions of the ADA,
certain conditions must be met. For example, the employee must work for a
covered employer and be a qualified individual with a disability, i.e., one
who can perform his or her job with or without reasonable accommodation. Thus,
while the ADA may offer some protection to an employee who has or is
suspected of having infectious TB or who cannot work because he or she cannot
wear a respirator, the protection proposed to be provided by the OSHA
standard for TB is more comprehensive and will lead to greater participation
in the entire medical surveillance program. The OSHA proposed standard, in
paragraph (g)(5)(ii), would provide to the employee with suspected or
confirmed infectious TB: *
* * his or her total normal earnings, seniority, and all other employee
rights and benefits, including the employee's right to his or her former job
status * * * until the employee is determined to be noninfectious or for a
maximum of 18 months, whichever comes first. For
each employee who must be removed for his or her job because he or she cannot
wear a respirator (paragraph (g)(5)(iii)), the employer is required to: transfer
the employee to comparable work for which the employee is qualified or can be
trained in a short period (up to 6 months), where the use of respiratory
protection is not required [and] * * * maintain the total normal earnings,
seniority, and all other employee rights and benefits. If there is no such
work available, the employer shall maintain the employee's total normal
earnings, seniority, and all other employee rights and benefits until such
work becomes available or for a maximum of 18 months, whichever comes first. OSHA's
MRP provisions provide each employee, who must be medically removed, with the
level of protection that is needed to assure that the employee promptly
reports his or her symptoms of TB (which makes the workplace safer for all
employees) and reports his or her difficulty with wearing a respirator (which
makes the workplace safer for that employee). Significant Alternatives to the Rule Considered by OSHA This
section first considers alternatives that OSHA was urged to consider by the
SBREFA Panel and then turns to other alternatives considered by the Agency. Alternatives Suggested by SBREFA Panel Members Small
entity representatives and SBREFA Panel members suggested a wide variety of
possible clarifications and alternatives to the regulation. In response to
these suggestions, OSHA has made a number of changes to the regulation,
clarified the meaning of many sections of the rule, provided additional
analysis, and added tables to the Preamble designed to clarify the
requirements of the rule in various situations. A full discussion of OSHA's
responses to all of the SBREFA Panel recommendations is given in the next
section. This section only presents alternative approaches to the proposed
rule and a discussion of the extent to which OSHA has adopted these
alternative approaches. OSHA welcomes comments on these and other
alternatives and on ways OSHA could adopt additional aspects of these
alternative approaches and still meet the requirements of the OSH Act,
particularly that Act's requirement to control significant risk to the extent
feasible. Less
Stringent Trigger Mechanisms for the More Burdensome Portions of the
Standard, Including Raising the Zero-Case Per County Per Year Trigger OSHA
has re-examined each provision of the proposed standard to ensure that it is
necessary and appropriate to reduce risk. In the draft of the proposal
reviewed by the Panel, OSHA required that a facility would only be eligible
for the reduced TB control program requirements of Appendix A if the facility
did not treat TB patients and if there had been no cases of TB in the county
or the facility in the previous year. In its review, OSHA found that applying
the standard's Appendix A requirements to facilities in counties with no TB
cases in one of the last two years and fewer than 6 TB cases in the other of
the last two years would not substantially increase the risk to employees in
facilities located in such counties. This change from the trigger OSHA
originally considered increases the number of counties qualifying for the
Appendix A program from 43 percent to 55 percent of all U.S. counties. Consider
Allowing Portability of Training The
draft proposal reviewed by the SBREFA Panel required that all new employees
be provided complete training. OSHA has examined its training provisions and
decided that the non-site-specific components of training, such as training
in the difference between tuberculosis infection and disease, can be
transferred between employers without reducing the protection such training
affords employees. Do
Not Require Annual Retraining The
draft proposal reviewed by the SBREFA Panel required annual retraining of all
employees. OSHA believes that some method of assuring continuing competency
is necessary, and that one-time training will not provide such assurance. However,
the proposal now would allow employers to develop methods of assuring the
competency of their employees, such as asking them questions about
procedures, controls, etc., as an alternative to retraining. This change in
the regulation will result in cost savings of $20 million per year. Cooperative
Initiatives, Such as Expanding OSHA's Current Cooperative Initiative With
JCAHO Some
Panel members felt that cooperative initiatives could substitute for
regulation in some areas. As noted above, however, in the absence of an OSHA
standard, HCFA (and accrediting associations working with HCFA, such as
JCAHO) does not have the authority to enforce specific infection control
requirements. As a result, a cooperative initiative alone would leave
employees exposed to TB in hospitals, who account for 13 percent of the
active cases of TB projected to be prevented by the standard, without any new
initiative designed to prevent these active cases of TB. If this approach
were extended to nursing homes, and all nursing homes chose to be accredited,
then 70 percent of the active cases of TB projected to be prevented by the
standard would be denied coverage. Thus, OSHA does not feel that cooperative
initiatives, even with accrediting organizations, can substitute for
regulation. Others
suggested that OSHA could turn over enforcement of any TB regulation to HCFA,
JCAHO or another accrediting or standards organization. In the eyes of its
proponents, the suggestion that others could enforce OSHA's regulation has
several major advantages. First, it would assure regular and more frequent
inspections at health care facilities and nursing homes than OSHA alone could
provide. Second, it would require health care facilities and nursing homes to
deal only with a single inspection for infection control procedures, rather
than inspections by two different federal agencies. Third, these
organizations may have greater penalty powers than OSHA, in that denial of
HCFA acceptance or of accreditation can result in a health care facility
losing significant funding or even being required to close. For
several reasons, providing exclusive HCFA enforcement of OSHA's TB
requirements is an unsound approach. First, OSHA inspectors already inspect
health care facilities, just as they inspect any other facility covered by
the OSH Act, for possible violations of any OSHA requirement, e.g.,
safety as well as health requirements. The need for these OSHA inspections
would not change even if HCFA or accrediting agencies enforced OSHA's TB
requirements. Second, OSHA does not believe that it is legally appropriate
under the OSH Act to tell its inspectors that, when they inspect health care
facilities, they must ignore violations of the Agency's occupational exposure
to TB requirements. Third, OSHA also cannot legally ignore employee
complaints relating to occupational exposure to TB. For all of these reasons,
OSHA believes that exclusive enforcement of the rule by HCFA or by agencies,
such as JCAHO, that are authorized to provide accreditation, is not an
appropriate or legally defensible approach. However,
OSHA does favor expanding its cooperative agreements, such as the current
agreement with JCAHO, in any ways that both agencies agree would be
beneficial, and OSHA is currently pursuing this option. On August 5, 1996,
OSHA and JCAHO announced a 3-year partnership to promote health and safety
for healthcare workers. This partnership will help health care facilities to
meet accreditation expectations and OSHA compliance requirements. The
initiatives of this partnership will include cataloging and evaluating
duplicative compliance activities; undertaking cross-education and training
of JCAHO and OSHA staff on corresponding requirements that relate to the
management of worker safety and health; and developing a series of collaborative
publications and user education programs. A
Federal-State Government Public Health Partnership to Develop Guidelines in
Various Industry Sectors The
CDC is already charged with developing guidelines for the control of TB, and
has already issued guidelines for correctional institutions, laboratories,
health care facilities, long-term care facilities for the elderly, and
homeless shelters. In fact, OSHA has made extensive use of these guidelines
in developing its proposed occupational exposure to TB standard. OSHA feels
that the CDC guidelines alone have not served adequately to protect
TB-exposed workers, however. OSHA research indicates that the CDC guidelines
are not being followed in most facilities, and believes that this is the
reason that occupational exposure to TB remains such a serious problem in
this country. In Chapter VII of the analysis, OSHA shows that these
guidelines are not being followed and explains why many employers have little
economic incentive to implement these guidelines. Performance
Standards Developed With the Assistance of Federal, State, and Local
Government, and Labor and Industry OSHA
feels that its standard is a performance oriented standard that has benefited
from both CDC's expertise and from many stakeholder meetings (which include
representatives of other federal, state and local government agencies, labor,
and industry) and the SBREFA Panel Process. OSHA's
proposed standard is performance oriented in a variety of ways. For example,
OSHA does not specify procedures by which facilities must achieve AFB
isolation, but instead allows any workable design. Similarly, OSHA sets
performance criteria for respirators, but does not specify the types of
respirators that must be used. OSHA does specify procedures for
identification of suspect cases, but allows any method that assures that
persons with the appropriate symptoms are identified as suspect cases. However,
OSHA did not consider it appropriate to specify performance in terms of rates
of TB cases or TB skin test conversions. Such an approach is not preventive,
in that application of proper procedures would only occur after TB infection
had occurred. Furthermore, most smaller facilities do not have enough TST
conversions for statistically meaningful trends to be established. OSHA
requests comments on this issue. Some
proponents of this approach feel that OSHA's proposed standard may not
reflect the best ideas for controlling occupational exposure to TB and argue
that stakeholder meetings would be a useful way of developing a better
approach. OSHA held five stakeholder meetings involving representatives from
more than thirty interested organizations. Furthermore, the CDC has made use
of the best expertise in the country in developing its guidelines, and OSHA
has adopted most elements of these guidelines and will hold public hearings
on the standard at which interested parties can present their views. OSHA
welcomes comments about alternative approaches to reducing occupational
exposure to TB, particularly suggestions concerning more performance oriented
approaches, but feels that this proposal is the result of an extensive review
of the literature and of input from stakeholders on the available prevention
and control methods and should be issued as a proposal at this time to prompt
further discussion and exchange of information. OSHA is particularly
interested in alternative methods of identifying suspected cases of TB and in
whether the proposed requirements would preclude or impede programs that
employers have found to be effective. Separate
Approaches for Health and Non-Health Industries The Approach for Health
Industries Should Be Keyed to Existing Industry Standards and That for
Non-Health Industries to Guidelines This
suggested alternative incorporates several concepts. First, it assumes that
the health and non-health care sectors should be given separate treatment
because of differences in existing regulations and expertise. OSHA agrees
that sectors that differ in relevant ways should be given different
treatment, and the standard therefore has provided for different approaches
to different sectors. For example, OSHA's standard does treat facilities that
treat TB patients differently from the way it treats those that transfer TB
patients out of their facilities, and treats employers whose employees are
routinely in contact with client populations with high rates of infectious TB
(such as homeless shelters and drug abuse treatment centers) differently from
employers whose employees only come into contact with infectious TB cases on
an occasional basis (such as attorneys and social workers). Second,
this alternative posits that the health care sector is already subject to an
extensive regulatory system with respect to occupational exposure to TB. Although
some states have laws on contact tracing and skin testing, and HCFA inspects
infection control systems in hospitals and long-term care facilities for the
elderly, there are no existing enforceable standards aimed specifically at
occupational exposure to TB. Thus OSHA's proposed provisions with respect to
preventive measures have no equivalent in existing regulations, and only a
limited number of states require skin testing of the kind OSHA's proposed
standard requires. OSHA (and CDC) believes that these provisions are
essential to any program to control occupational exposure to TB. Third,
proponents of this alternative believe that the non-health care sectors,
particularly those engaged in charitable work such as homeless shelters, are
better approached through guidelines than regulations. OSHA believes that
there is relatively little need to develop guidelines for non-healthcare
sectors, such as correctional institutions and homeless shelters, because
such guidelines already exist and have not been implemented in many, if not
most, facilities. Some proponents of this approach believe that the failure
of non-health care sectors to implement existing guidelines is due to the
absence of outreach and information. OSHA is not substituting a system of
regulation for a system of outreach. OSHA intends to continue a program of
outreach on occupational TB, and hopes that facilities in all sectors will
adopt appropriate policies before the regulation is finalized. However, given
that even in the relatively knowledgeable health care sector, implementation
of the CDC guidelines has been limited, it is unlikely that outreach alone
can assure the full implementation of suitable measures for control of
occupational exposure to TB. Different
Levels of Requirements for Different Industries, Depending on Their
Expertise, Resources, and Risk OSHA's
proposed standard recognizes three levels of risk and provides separate
treatment for employers engaged in different kinds of activities, where those
differences are relevant to the purposes of the standard. This subject is
discussed in the next sections. Such tailoring, however, must be consistent
with the mandate of the Occupational Safety and Health Act to reduce
significant risk to the full extent feasible. OSHA has preliminarily found
all of the standard's provisions to be technologically and economically
feasible, within the meaning of the Act, for facilities in all affected
industries. (The special potential problems of homeless shelters and
substance abuse treatment centers are discussed further below.) The statutory
requirement to eliminate significant risk to the extent feasible means that
if inadequate resources and expertise would make any provision of the
proposed standard infeasible, then OSHA would have to consider alternative
approaches. However, it also means that the resources and expertise that are
feasible for an employer to acquire must be employed if they will reduce
significant risk. Separate
Standards for Each Affected Industry Proponents
of this alternative had two goals: first, to assure that OSHA gave full
consideration to the circumstances of each affected industry, and second, to
make the standard easier to follow for affected small entities. With respect
to the first goal, OSHA has recognized a wide variety of distinctions in risk
of exposure and practice among affected employers. Some of these differences
follow industry lines. Accordingly, the proposed standard includes special
provisions for laboratories and home health care providers. However, most of
the relevant differences among employers do not strictly follow industry
lines, and attempts to write separate standards for different industries
would not significantly reduce the complexity of the regulation. For example,
all industries need to realize that different requirements are applicable for
each of three types of risk of exposure. Similarly, the applicability of
certain requirements depends on whether TB patients are treated onsite and on
whether certain hazardous procedures are performed. While, for example, the
typical nursing home would not treat TB patients or perform high hazard
procedures on site, some might, and thus these provisions would need to be
included in an industry standard written for nursing homes. OSHA's proposed
standard carefully distinguishes a variety of activities that may occur in
different industries and has different requirements for each activity. Although
this makes the standard somewhat more complex, this approach is essential to
avoid a "one size fits all" standard. In addition, as presented in
the discussion of the scope in the Summary and Explanation of the Preamble,
OSHA has developed charts showing the requirements of the proposed standard
that are applicable to each industry. OSHA welcomes any suggestions on ways
to make the standard easier to understand, or on ways to adapt the standard
to the situation of specific industries while reducing significant risk. Revise
the Proposed Standard for Consistency With CDC Guidelines The
issue of how the CDC Guidelines fit into a regulatory scheme to prevent or reduce
occupational exposure to TB has been considered by OSHA and other reviewers. OSHA's
view is embodied in the proposed standard, in which the Agency has attempted
to translate the CDC's recommendations into enforceable regulatory language
that can be applied to a variety of occupational settings where the risk of
transmission of TB is significant. The Agency believes that, in addition to
the basic difference between a "guideline" and a
"regulation," there are only three general areas where the proposed
standard differs substantially from the CDC Guidelines for health care
facilities: the use of site-specific risk assessment, the frequency of skin
testing in certain situations, and the required use of respiratory protection
around unmasked individuals with suspected or confirmed infectious TB. Several
small entity representatives, along with some SBREFA Panel members, have
suggested that the Agency consider allowing employers to follow the CDC
Guidelines as an additional option to comply with the OSHA standard. Both
the OMB and SBA Panel representatives believe that for at least some of the
work sites OSHA has proposed to cover, the CDC Guidelines currently provide
an adequate measure of protection. They believe it would be burdensome for
employers who are already in compliance with the Guidelines to have to become
familiar with the OSHA proposal and to implement its provisions. These
employers have already invested in a TB prevention and response program
consistent with the Guidelines. In other words, the employers have conducted
their risk assessments, implemented the suggested provisions and trained
their workers to comply. Moreover, these reviewers point out that where the
Guidelines have allowed for discretion on the part of the employer as, for
example, where an employer may first consider the symptoms specified in the
several CDC Guidelines' definition of "suspected infectious TB"
before adopting a definition for his or her own work site, prevention of the
transmission will more easily be achieved because the employer is allowed to
tailor the requirements to actual conditions in his or her workplace. To
assure that the employer's adoption of the CDC Guidelines is effective, these
reviewers recommended that the employer assert or certify that he or she is
in compliance and, if challenged in an OSHA inspection, prove the efficacy of
his or her program through a performance measure, such as skin test
conversion rates. These reviewers believe that this approach will result in a
more efficient use of scarce health resources. OSHA
agrees that the various CDC Guidelines are the most important sources for
setting an occupational health standard that will reduce or prevent the
spread of TB. However, although certain facilities adhere to the Guidelines,
OSHA's research has shown that most facilities have not fully implemented the
CDC recommendations. TB remains an occupational hazard, and OSHA has
preliminarily concluded that the risk of transmission of TB to employees is
significant. OSHA believes there are a number of reasons why the Guidelines
cannot take the place of an OSHA standard. First, the Guidelines are not
written in language that can be enforced. For example, the Guidelines
suggest, recommend and set forth what an employer could or should do, not
what he or she must do. Unless the Guidelines are converted to regulations,
an employer may adhere to some applicable recommendations while not
implementing others, which could result in uneven and inadequate employee
protection. OSHA standards are written in mandatory language, letting
employers and employees know what they have to do in order to be in
compliance with the regulation. This permits an employer, an employee or a
compliance officer to determine easily whether an entity is in compliance
with a standard. Second, the establishment-specific risk assessment approach
of the Guidelines imposes a tremendous paperwork burden on covered entities
and requires a level of professional expertise in risk assessment that few
entities outside of large hospitals possess. OSHA believes that
recommendations or regulations that necessitate this level of expertise could
make it difficult to determine if an entity is in compliance. Third, OSHA
knows of no objective criterion that could be reliably used as a measure of
proof of an effective program. Tuberculin skin testing has been suggested as
a means of proving compliance with the CDC Guidelines, e.g., zero
conversions would be accepted as proof that an entity was complying with the
Guidelines. However, the use of conversions as a compliance measurement has
two problems. First, skin test conversions are not necessarily indicative of
implementation of the Guidelines' recommendations. For example, an entity may
have implemented very few of the Guidelines' recommendations, yet been
fortunate enough to experience no conversions. Therefore, compliance with the
Guidelines' recommendations has not been achieved even though there have been
no employee conversions. Furthermore, while an increase in the number of
conversions indicates employee exposure, a lack of conversions does not
necessarily mean that employees are not being exposed. For example, some
employees have already skin-tested positive, not all exposures result in
conversions, and many entities will not have enough TST-negative employees to
generate sufficient statistical power to accurately determine an increased
conversion rate. With regard to this last point, the CDC states: A
low number of HCWs in a specific area may result in a greatly increased rate
of conversion for that area, although the actual risk may not be
significantly greater than that for other areas. Testing for statistical
significance (e.g., Fisher's exact test or chi square test) may assist
interpretation; however, lack of statistical significance may not rule out a
problem (i.e., if the number of HCWs tested is low, there may not be adequate
statistical power to detect a significant difference). Thus, interpretation
of individual situations is necessary. (Ex. 4B) Second,
OSHA believes that reliance on number of TST conversions as a performance
measure is reactive rather than proactive, because it emphasizes the
identification of employees who have already incurred a status change as a
result of an exposure instead of averting exposures. OSHA
believes that compliance with the proposed standard by all affected
facilities within the covered sectors is the way to assure that employees
will be protected from occupational transmission of TB. The Agency believes
that compliance will not be difficult for employers who have already
implemented the Guidelines, because many of the elements of the Guidelines
have been incorporated into the proposed standard. Also, employers who are
not in compliance with the Guidelines will find that the standard gives them
clear instructions on what to do. In addition, the structure of OSHA's
proposed TB standard is similar to that of the Bloodborne Pathogens standard
(BBP). Since the vast majority of workplaces that will be covered by the TB
standard are subject to BBP, becoming familiar with and implementing the
requirements of the TB standard should not be difficult. Another
issue raised in the review process was what would happen if, after the OSHA
standard was promulgated, the CDC issued a new guideline that was different
from the OSHA standard on an item addressed by the standard. OSHA believes
this is already addressed by OSHA's citation policy, in particular, the
policy for De Minimis Violations, which states that violations of standards
which have no direct or immediate relationship to safety or health are not to
be included in citations. An example of a de minimis violation occurs when an
employer complies with a proposed OSHA standard or a consensus standard
rather than with the OSHA standard in effect at the time of the inspection
and the employer's action clearly provides equal or greater employee
protection [OSHA Field Inspection Reference Manual, Instruction CPL 2.103,
September 26, 1994]. In cases where an employer is complying with another
provision, such as a consensus standard, the Agency looks at the consensus
standard to make sure the consensus standard is at least as protective as the
OSHA standard. Because CDC Guidelines reflect the views of many of the
country's leading experts and practitioners in public health measures to
prevent the spread of TB, the updated CDC Guidelines can be assumed to
provide equal or greater protection against occupational transmission of TB
to employees. Because these guidelines carry great authority, the De Minimis
Violation policy would not only be a defense, but would be accorded such
deference that OSHA would incur a heavy burden in showing that an updated CDC
guideline on an item addressed by the OSHA TB standard did not provide equal
or greater protection against occupational transmission of TB to employees. In
order to ensure that the new CDC Guidelines would be communicated to the OSHA
Regions and others who would need to know, OSHA will issue a Memorandum for
Regional Administrators that will address how the new Guideline could be
implemented in the work place, include a copy of the new Guideline, and
instruct the Regional Administrator to contact area offices and the OSHA
state designees. In addition, the Memorandum would be posted on the OSHA
Computer Information Service (OCIS) and OSHA CD-ROM, which are accessible to
the public. OSHA
seeks comment on all issues related to the CDC Guidelines, particularly
whether they could be implemented in lieu of an OSHA standard and, if so, how
compliance and efficacy could be determined. Change
the Approach to the Identification of Suspect Cases for Homeless Shelters or
Substance Abuse Treatment centers The
SBREFA Panel found that "Given the current definition of suspect cases,
it is not clear that homeless shelters can comply fully with the standard. Accordingly,
OSHA should reexamine the definition of suspect cases and/or reexamine its
approach to homeless shelters." The SBREFA Panel also noted that this
same finding might be relevant to substance abuse treatment centers. The
Panel arrived at this finding as a result of statements made by small entity
representatives from the homeless shelter sector. Small entity
representatives concerned with homeless shelters had serious problems with
OSHA's definition of a suspect case and questioned the feasibility of
screening the homeless by using questions about symptoms. Mr. Wayne Anderson
of the National Health Care for the Homeless Council argued that OSHA's
definition of a suspect case would result in the identification of most of
the homeless as suspect cases during the winter months. Major Dalberg of the
Salvation Army found OSHA's definition of a suspect case confusing and
ambiguous, and stated that it would cover a substantial portion of the
homeless. All three small entity representatives from this sector questioned
whether the standard's screening procedures were workable in the homeless
shelter context. They asserted that the homeless might avoid screening
questions, be unable to answer them, learn how to lie in response to such
questions, or choose to remain on the street rather than be transferred to a
hospital. The small entity representatives for this sector felt that this
portion of the standard should be abandoned. Because substance abuse
treatment centers serve a similar clientele, the Panel was concerned that the
same problems might apply to substance abuse treatment centers. To
address this issue, and other issues related to the feasibility of the
proposed standard for homeless shelters, OSHA has decided to hold special
sessions during the public hearings on the proposed standard and to study
these issues further through an onsite survey of a number of homeless
shelters. The study will address the following issues:
-- Methods of isolation.
-- Costs of running a shelter.
The
study will also address the issue of volunteers. The OSH Act applies to employees,
not bona fide volunteers; however, OSHA understands that some states may, as
a matter of state law, require facilities to provide volunteers with the
protections established by OSHA standards. Thus, OSHA's study will address
the following issues:
The
results of the study will be made available for comment in the public record. OSHA
does not feel that the same problems apply to substance abuse treatment
centers, even if a high percentage of clients might be defined as suspect
cases. Inpatient substance abuse treatment centers routinely provide some
form of entrance physical: this would be an appropriate time to screen for
suspect cases and provide for their referral. Outpatient
substance abuse treatment centers do not provide any form of shelter for
patients, and thus could readily refer suspect cases to a hospital without
either denying them shelter or having to pay for the referral. Such a
facility could simply insist that suspect cases not return without data
showing that they had been to a doctor and did not have TB. Since outpatient
facilities handle a known population, such an approach might involve high
initial referrals, but could thereafter settle into a system that checked for
suspect cases on entry to the program. OSHA
estimates that the proposed standard will result in a reduction of 28 to 33
active disease cases and 2 to 3 deaths per year in the homeless shelter
sector. A standard requiring skin testing and follow-up treatment alone would
have only one third the benefits (such an approach would reduce the number of
active disease cases to only 10 per year and the number of lives saved to 1
per year). The annual costs of the proposed standard for homeless shelters
are estimated to be $11,287,278, or approximately $1,080 per shelter per
year. OSHA
solicits comments on all of the issues listed above to be covered by its
study of homeless shelters, and solicits comment on the feasibility of the
standard for substance abuse treatment centers, and particularly on the
extent to which substance abuse treatment centers already provide for medical
examinations prior to entry into their programs. Other
Alternatives Considered by OSHA OSHA
considered several additional alternatives but has preliminarily concluded
that the proposed rule will better carry out the objectives of the OSH Act,
while minimizing the economic impact on affected establishments, and
especially on small establishments. OSHA requests comment on the validity of
this preliminary conclusion. First, OSHA considered making all of the
proposed requirements applicable to every establishment in the covered
industries. The prevalence of TB, however, varies by geographical areas and
by the populations served by facilities in different industries. OSHA
therefore believes it will be possible to reduce significant risk without
imposing the full regulatory requirements on each covered employer. Second,
OSHA considered proposing requirements similar to the CDC's guidelines, which
recommend that risk assessments be conducted to determine the level of risk
in each facility and that the controls implemented vary in accordance with
the level of risk in each facility. This would require that employers conduct
risk assessments by evaluating factors, such as the number of suspected or
confirmed TB cases among patients and employees, employee tuberculin skin
testing results, and the amount of TB in the community. The CDC
recommendations include five levels of risk (i.e., minimal, very-low, low,
intermediate, and high), and the recommended controls vary by the level of
risk. However, adopting such a requirement in the OSHA standard would impose a
large cost and a heavy paperwork burden on affected facilities. To
avoid imposing unnecessary burdens on facilities where the risk of
occupational exposure to M. tuberculosis may be lower, OSHA is
proposing to exempt facilities from certain requirements (i.e., respiratory
protection, annual medical histories, and annual skin tests) if the facility
transfers, instead of admits, individuals with suspected or confirmed
infectious TB and can additionally demonstrate that there have been (1) no
reported confirmed infectious TB cases in the county within one of the last
two 12-month reporting periods; (2) fewer than 6 infectious cases of TB in
the other 12-month reporting period; and (3) no infectious cases of TB
encountered within their employees' work settings within the past 12 months. OSHA
also considered proposing a requirement that facilities implement engineering
controls in all intake areas in which early identification procedures are
performed, if the facility had encountered six or more individuals with
confirmed infectious TB in the past 12 months. The engineering controls
considered were single-pass ventilation, filtration of air through the use of
HEPA filters installed as part of the ventilation system, or stand-alone
auxiliary HEPA filtration units. However, areas where early identification
procedures are performed vary widely in size and configuration, making it
difficult to assess the effectiveness of such controls in reducing the risk
of occupational exposure to M. tuberculosis in a particular setting. Given
the high cost of such controls and the lack of data on their effectiveness,
OSHA is not proposing such a requirement. However, the Agency requests
comment on the potential effectiveness of such controls in intake areas. Another
alternative considered was to propose that each occupationally exposed
employee be provided with a baseline medical examination, including a
physical examination that emphasized the pulmonary system and an evaluation
for the signs and symptoms of active TB disease and factors affecting
immunocompetence. However, requiring a baseline physical examination for all
exposed employees would impose a heavy cost burden on affected
establishments, and OSHA could find no evidence that providing a baseline
physical examination would accomplish more than a baseline and annual medical
history and tuberculin skin test in identifying or reducing occupationally
induced TB infections. Thus, OSHA is proposing to require physical
examinations only when they are deemed necessary by the physician or other
licensed health care professional, as appropriate. OSHA
also considered providing medical management and follow-up to each employee
who had been exposed to air originating from an area where an individual with
suspected or confirmed infectious TB was present. However, stakeholders
contacted prior to the issuance of this proposal stated that a requirement
for medical management and follow-up would impose an unnecessary burden on
affected establishments for those cases that were suspected but were
subsequently ruled out. In response to stakeholders' comments, the Agency is
proposing that medical management and follow-up be provided only when an
employee is actually exposed to an individual with confirmed infectious TB or
to air containing aerosolized M. tuberculosis without the benefit of
the applicable exposure control measures (e.g., respiratory
protection) that would be required under the proposed rule. Another
alternative considered was to require tuberculin skin tests every six months
for all employees assigned to wear respirators. However, to reduce the burden
on facilities that do not encounter many infectious TB cases, OSHA is not
requiring 6-month skin testing for workers assigned to wear respirators and
who work in the intake areas of facilities where fewer than six confirmed
infectious TB cases are encountered each year. Rejecting
these regulatory alternatives has reduced the estimated costs of the proposed
rule by a minimum of $100 million. The
RFA emphasizes the importance of performance-based standards for small
businesses. OSHA considers the proposed standard to be highly performance
oriented. The proposed standard emphasizes the early identification and
isolation of individuals with suspected or confirmed infectious TB. Affected
employers have been allowed wide discretion in the selection of procedures
they use to achieve this. Without early identification and isolation,
prevention of the spread of TB from patients and clients to workers is
virtually impossible. OSHA has also limited requirements for work settings
located in a county that, in the past 2 years, has had zero cases of
confirmed infectious TB reported in one year and fewer than 6 cases of
confirmed infectious TB reported in the other year. OSHA welcomes comment on
other ways that the standard can be made more performance oriented. Another
approach considered is compliance date phase-ins for small businesses. OSHA
is proposing to extend the standard's compliance deadlines for engineering
controls and has considered extending the compliance deadlines for the other
proposed requirements; however, since these other requirements are not
capital-intensive for most affected facilities, such an extension would do
little to reduce the burden on small entities and would only result in a delay
in the protection of workers provided by compliance with the proposed rule. OSHA
solicits comment on the effects of extending phase-in dates for the other
proposed requirements, particularly those for respirators, for small
entities. After
considering all of the above alternatives and adopting those that were
consistent with the mandate imposed by the OSH Act, OSHA has developed a
proposed rule that will minimize the burden on affected employers, while
maintaining the necessary level of worker protection. OSHA's
Response to SBREFA Panel Recommendations Table
VII-7 lists the SBREFA Panel Recommendations and OSHA's response to these
recommendations. The complete SBREFA Panel Report is available for comment in
the record as Exhibit 12 of Docket H-371. VIII. Unfunded Mandates Analysis The
proposed TB standard has been reviewed in accordance with the Unfunded
Mandates Reform Act of 1995 (UMRA) (2 U.S.C. 1501 et seq.) and
Executive Order 12875. OSHA estimates that compliance with the proposed
standard will require expenditures of more than $100 million each year by
employers in the private sector. Therefore, the proposed TB standard
establishes a federal private sector mandate and is a significant regulatory
action within the meaning of Section 202 of UMRA (2 U.S.C. 1532). OSHA has
included this statement to address the anticipated effects of the proposed TB
standard pursuant to Section 202. OSHA
standards do not apply to state and local governments except in states that
have voluntarily elected to adopt an OSHA State Plan. Consequently, the
proposed TB standard does not meet the definition of a "federal
intergovernmental mandate" (Section 421(5) of UMRA (2 USC 658 (5)). In
sum, the proposed TB standard does not impose unfunded mandates on state,
local, and tribal governments. The
remainder of this section summarizes OSHA's findings as required by Section
202 of UMRA (2 U.S.C. 1532): This
standard is proposed under Section 6(b) of the OSH Act. The proposed standard
has annualized costs estimated at $245 million and would save an estimated
138 to 190 lives per year as a result of TB infections avoided. An estimated
1,772 to 2,442 active TB cases will be averted annually as a result of the
proposed rule. Compliance will also result in an estimated 24,333 to 32,719
infections averted. The proposed standard will impose no more than minimal
costs on state, local or tribal governments. OSHA pays 50 percent of State
plan costs but does not provide funding for state, local or tribal
governments to comply with its rules. OSHA
does not anticipate any disproportionate budgetary effects upon any
particular region of the nation or particular state, local, or tribal
governments, or urban or rural or other types of communities. Chapters V and
VI of the economic analysis provide detailed analyses of the costs and
impacts of the proposed standard on particular segments of the private
sector. OSHA has analyzed the economic impacts of the standard on the
affected industries and found that compliance costs are, on average, only
0.18 percent of sales, and that few, if any, facility closures or job losses
are anticipated in the affected industries. As a result, impacts on the
national economy would be too small to be measurable by economic models. OSHA
requests information on state and local government issues. Pursuant
to Section 205 of the UMRA (2 U.S.C. 1535), and having considered a variety
of alternatives outlined in the Preamble and in the Regulatory Flexibility
Analysis above, the Agency preliminarily concludes that the proposed rule is
the most cost-effective alternative for implementation of OSHA's statutory
objective of reducing significant risk among employees to the extent
feasible. OSHA solicits comment on these issues. IX. Environmental Impacts The
provisions of this proposed standard have been reviewed in accordance with
the requirements of the National Environmental Policy Act (NEPA) of 1969 [42
U.S.C. 432, et seq.], the Council on Environmental Quality (CEQ) NEPA
regulations [40 CFR Part 1500], and OSHA's DOL NEPA Procedures [29 CFR Part
11]. As a result of this review, OSHA has preliminarily determined that this
proposed standard will have no significant effect on air, water, or soil
quality, plant or animal life, use of land, or other aspects of the
environment. X. Summary and Explanation of the Standard Based
on currently available data in the record, OSHA has preliminarily concluded
that the requirements set forth in this proposed standard are those that are
necessary and appropriate to provide adequate protection to employees exposed
to tuberculosis (TB). In the development of this proposed standard, OSHA has carefully
considered the numerous reference works, journal articles, and other data
collected by OSHA since the initiation of this proceeding. In particular,
OSHA has carefully considered the recommendations given in the document,
"Guidelines for Preventing the Transmission of Mycobacterium
tuberculosis in Health-Care Facilities" published by the Centers for
Disease Control and Prevention beginning on page 54242 in the Federal
Register of October 28, 1994 (Ex. 4B). OSHA also held a series of
informal stakeholder meetings during the development of the proposal and
considered the major points raised by the stakeholders during these meetings
(Ex. 10). In addition, the proposal has undergone the Panel review process
required by the Small Business Regulatory Enforcement Fairness Act (SBREFA)(5
U.S.C. Chapter 8) (Exs. 11 and 12). All of the information developed to
assist the small entity representatives involved in the SBREFA panel process,
the comments of these representatives, and the Panel's findings and recommendations
to OSHA have been placed in the rulemaking record (Exs. 11 and 12). Upon
publication of the final standard, the Agency will undertake a number of
compliance assistance activities that will be particularly beneficial to
small entities. Past compliance assistance activities have included:
publication of booklets summarizing the provisions of the standard;
development of a compliance directive that answers compliance-related
questions about the standard; development of compliance guides directed at assisting
small businesses in complying with the standard; designation of certain OSHA
employees in each Regional office with the responsibility of answering
questions from the public about the standard; development of training
materials; and provision of speakers and information for meetings and
workshops of affected parties (particularly small business entities). OSHA
anticipates initiating similar activities upon publication of the final
standard for occupational exposure to tuberculosis. Paragraph (a) Scope Tuberculosis
is a well-recognized occupational hazard (Ex. 4B). As discussed in the Health
Effects section above, there are numerous epidemiological studies, case
reports, and outbreak investigations that provide evidence to show that
employees who are exposed to aerosolized M. tuberculosis have become
infected with TB and in some cases have developed active TB disease. Of
particular concern is the emergence of strains of multidrug-resistant TB. MDR-TB
presents an additional hazard because individuals with MDR-TB may be
infectious for weeks or months until an effective drug regimen can be
successfully implemented and the patient rendered noninfectious. This in turn
increases the likelihood that employees who must provide health care or other
services to these individuals will be exposed. The risk of death from
infections with MDR-TB is markedly increased. Outbreaks involving strains of
MDR-TB have had mortality rates as high as 75 % with death occurring 4 to 16
weeks after the diagnosis of disease (Ex. 3-38A). Most
of the TB outbreaks investigated occurred in large metropolitan areas. However,
a recent study has shown that MDR-TB spread from New York City to patients in
Florida and Nevada and <<health care workers>> in Atlanta, Georgia and Miami,
Florida and to staff and patients in a nursing home in Denver, Colorado (Ex.
7-259). In addition, a growing percentage of TB cases are occurring among the
foreign born. CDC reported that in 1995 the number and proportion of cases
among the foreign-born had increased 63 % since 1986 (Ex. 6-34). These two
pieces of information taken together clearly illustrate the relationship
between population mobility and the spread of TB disease. Thus, TB is a
nationwide problem. Although the total number of cases declined to its
pre-1985 levels after a resurgence from 1985 to 1994, the rate of active TB
cases reported in 1995 (i.e., 8.7/100,000) is still two and one half times
greater than the target rate of 3.5 active cases per 100,000 population for
the year 2000 proposed by the Advisory Committee on the Elimination of
Tuberculosis (Ex. 6-19). In addition, there is substantial variability from
year to year in the increases and decreases in the number of cases reported
by each state. In 1995, all fifty states reported cases of TB, and fifteen of
these reported increases over 1994 (Ex. 6-34). At the county level,
approximately 57 % of counties in the U.S. reported one or more cases of
active TB, with 17 % of the counties in the U.S. reporting 5 or more cases
(Ex. 7-262). In addition, approximately 91 % of the U.S. population resides
in the counties that reported one or more cases of active TB. Thus, while 43
% of the counties in the U.S. reported no cases of active TB, 10 % of the
U.S. population resides in those counties. The nationwide prevalence of TB
infection in the U.S. population in 1994 (age 18 years an older) is
approximately 6.5 percent. The
recent resurgences in the number of reported cases of active TB have brought
to attention a number of problems in existing TB control plans. The problem
is most apparent in health care facilities such as hospitals, but it also
extends to other work settings where the population served is at increased
risk for tuberculosis, such as shelters for the homeless, correctional
institutions and settings where high-hazard procedures are performed. There
are a number of factors that make occupational exposure to tuberculosis an
important concern at the present time. One factor is that the results from
OSHA's quantitative risk assessment show a high potential for TB infection
for employees who work in close proximity to individuals with infectious TB. A
second factor is that the cases of tuberculosis are not distributed evenly
throughout the entire population. There is a relatively high prevalence of
tuberculosis infection and disease in certain populations, such as residents
of nursing homes and inmates of correctional institutions. A third factor is
the rise of MDR-TB. These factors increase the risk for workers who have
occupational exposure. Occupational exposure occurs through contact with air
that may contain aerosolized M. tuberculosis as a result of the
performance of an employee's duties. Most often this occurs when an employee
is working in the same environment with an individual with infectious TB. It
could also occur when repairing air systems that may be carrying aerosolized M.
tuberculosis. Individuals
with infectious tuberculosis expel airborne particles called droplet nuclei
when they cough, sneeze, or speak. These droplet nuclei contain the organism
that causes tuberculosis, M. tuberculosis. Normal air currents can
keep these droplet nuclei airborne for long periods of time and spread them
throughout a building (Ex. 5-5). When employees breathe the air that contains
M. tuberculosis, they are at risk for TB infection which may result in
illness and, in some cases, death. Employees also may be exposed when
laboratory procedures produce aerosols of M. tuberculosis. There is an
extensive discussion of the scientific literature related to occupational
transmission in Section IV, Health Effects, which will not be repeated here. Because
the CDC does not consider fomites, e.g., objects such as clothing or
silverware, to present a hazard for transmission of M. tuberculosis,
this standard is designed to eliminate or reduce airborne exposures only. Even
though it is well established that exposure to TB contaminated air is the
route of exposure related to the development of disease, it is not known what
levels of contamination in the air cause the disease. Unlike toxic chemicals,
a Permissible Exposure Limit (PEL) for air concentration of TB cannot be
determined. As described in the Health Effects section of this preamble, it
is known that a number of factors contribute to the probability of infection.
For example, exposures of relatively short duration, such as a day or two,
can result in infection of the employee. OSHA has used these findings to show
that certain types of work, in certain industries, can result in significant
risk of TB infection. For these reasons, OSHA is defining the scope of the
standard by listing the locations and services where this proposed standard
would apply. Employers with employees working at those locations, and employers
whose employees provide the listed services, are covered by the standard. The
proposed standard applies to occupational exposures to tuberculosis that
occur in certain specified workplaces, such as a hospital, or as the result
of providing services, such as emergency medical treatment. Paragraphs (a)(1)
through (10) of the proposal describe the various work settings and services
that are covered under the scope of the standard. Paragraph
(a)(1) states that the standard applies to occupational exposure to TB
occurring in hospitals. The record contains many examples of occupational
exposures with resultant TB infection and disease that have occurred in
hospitals (e.g., Exs. 5-11; 5-15; 7-43; 7-45). Recent outbreaks
involving multidrug-resistant strains of M. tuberculosis have
compounded the long recognized risk of TB in such settings. Hospitals
not only provide medical care for persons with diagnosed tuberculosis, they
also provide medical care for individuals who may be at increased risk for
TB. For example, hospitals provide isolation for individuals with suspected
or confirmed infectious TB and contain rooms or areas where high-hazard
procedures on individuals with infectious TB are performed that place
employees at risk of exposure. In addition, the client population encountered
in hospitals is generally at higher risk of developing active TB. Individuals
with HIV disease, for example, are at increased risk for developing disease
when they have been infected with M. tuberculosis. In addition,
medically underserved populations with an increased prevalence of
tuberculosis (e.g., homeless persons) may seek acute care in the
emergency rooms of hospitals. Employees
who are at risk for occupational exposure and potential infection and disease
include all employees who have direct contact with persons with infectious
tuberculosis. These may include but are not limited to physicians, nurses,
aides, dental workers, medical technicians, workers in laboratories and
autopsy suites, and emergency medical service personnel (Ex. 4B). They may
also include persons not involved in direct patient care but who have
occupational exposure as a result of providing other services such as
dietary, housekeeping, and maintenance staff. Paragraph
(a)(2) covers occupational exposure occurring in long-term care facilities
for the elderly. Persons aged 65 and older constitute a large repository of M.
tuberculosis infection in the United States (Ex. 6-14). Many of these
individuals were infected many decades ago when TB was a much more common
disease. Some of the TB occurring in this age group arises from preexisting
infection of long duration and other cases may be the result of recent
infections. In addition, elderly persons residing in nursing homes are at
greater risk than elderly persons living in the community. In its 1990
guidelines, "Prevention and Control of Tuberculosis in Facilities
Providing Long-term Care to the Elderly," the CDC cited 1984-1985 data
indicating a TB case rate of 39.2 per 100,000 population, a rate that was
twice that of elderly persons living in the community (Ex. 6-14). The same
document stated that CDC had found that the increased risk for nursing home
employees was three times higher than the rate expected for employed adults
of similar age, race, and sex. Examples of employees in long-term care
facilities who may have occupational exposure include, but are not limited
to, registered nurses, licensed practical nurses, nursing assistants, and
auxiliary personnel. OSHA has not included other long-term care facilities
under the scope of the standard. The Agency requests comment and supporting
data on whether it is appropriate to expand the scope of the standard to
include other long-term care facilities that may provide health care or other
services to individuals who may be at an increased risk of developing
infectious TB, thereby presenting a potential source of exposure to employees
working in those facilities. An example of another long-term care facility is
a psychiatric hospital. Paragraph
(a)(3) covers occupational exposure occurring in correctional facilities and
other facilities that house inmates or detainees. Facilities such as prisons,
jails and detainment centers operated by the Immigration and Naturalization
Service (INS) would be included in the scope of the standard. The CDC
considers TB to be a "major" problem in correctional institutions,
with cases occurring at a frequency three times that of the general
population (Ex. 7-25). In addition to a number of outbreaks that have
occurred, the overall incidence of tuberculosis in the prison population is
increasing. This can be attributed to, (1) the over-representation of
populations at high risk for TB in prisons and jails, and (2) environmental
factors that promote the transmission of TB. Compared to the general
population, inmates have a higher prevalence of TB infection. The population
of correctional facilities is also characterized as having a high prevalence
of individuals with HIV infection and intravenous drug users, factors that
place these inmates at a higher risk of developing active TB. In addition,
many prisons and jails are old, overcrowded, and have inadequate ventilation.
Inmates may be moved frequently within a facility and between facilities,
increasing the number of persons, both inmates and employees, exposed to an
infected individual and making contact tracing difficult. Medical
records and treatment information may not follow the inmate in a timely
manner, which may, in turn, lead to inadequate drug therapy. Detention
facilities, such as those operated by the INS, may house persons who are
entering this country from countries with a prevalence of TB many times that
of the U.S. population (Ex. 6-26). In addition, there may be a substantial
number of individuals in these facilities currently awaiting deportation who
have an additional increased risk of TB because they have been previously
incarcerated in correctional institutions. In 1995, CDC reported that
approximately 36 % of the total reported cases of active TB were among the
foreign-born (Ex. 6-34). This marks a 63 % increase since 1986. In addition,
among those persons whose records contained information on date of arrival to
the U.S., approximately 30 % developed active TB within one year of entering
the country and approximately 53 % developed active TB within 5 years of
entering the country. Employees who may have occupational exposure in these
facilities include, but are not limited to, correctional officers,
physicians, dentists, nurses, and other <<health care workers>>. Paragraph
(a)(4) covers occupational exposure occurring in hospices. CDC identified
hospices as one of the inpatient health care facilities to which its 1994 TB
guidelines apply. CDC's Guidelines recommend that individuals with suspected
or confirmed infectious TB be managed in the same manner using similar
methods of infection control as recommended for hospitals. Hospices serve the
same high-risk populations that hospitals serve. In addition, individuals receiving
hospice care may be at increased risk for tuberculosis if they are members of
a high risk group, which includes groups whose members have a medical
condition that increases the likelihood of developing active tuberculosis (e.g.,
HIV disease, end stage renal disease, certain carcinomas). Employees who may
have occupational exposure include, but are not limited to, physicians,
nurses, aides, social workers, and other <<health care workers>>. Occupational
exposure occurring in shelters for the homeless is covered under paragraph
(a)(5). Residents of shelters for the homeless comprise a population that is
also at increased risk for tuberculosis. Members of this population are more
likely to have risk factors that are associated with TB than the general
population although the exact prevalence of TB in this population is unknown.
The data quoted in CDC's 1992 document "Prevention and Control of
Tuberculosis Among Homeless Persons" indicated a prevalence of
clinically active tuberculosis among homeless adults ranging from 1.6 % to
6.8 % (Ex. 6-15). The prevalence of latent tuberculosis ranged from 18 % to
51 % and there was a point prevalence of active TB of 968 cases/100,000
homeless adults (Ex. 6-15). Similar to the population in correctional
facilities, residents of homeless shelters have a high prevalence of HIV
infection and intravenous drug use, factors that increase the likelihood that
their infections will progress to active TB. In addition, environmental
factors such as overcrowding and poor ventilation promote the transmission of
disease. Examples of employees who may have occupational exposure include,
but are not limited to, intake workers and <<health care workers>> who have contact with residents
of homeless shelters. Paragraph
(a)(6) covers occupational exposure occurring in facilities that provide
treatment for drug abuse. Based on tuberculin skin testing reported in 1993,
13.3 % of the clients of drug treatment facilities had evidence of TB
infection (Ex.6-8). Many of these persons have a history of intravenous-drug
use and either have or are at risk for HIV infection. These persons are at
increased risk for developing active TB and transmitting the disease to
others. Many of these individuals may discontinue treatment prematurely even
if they are diagnosed and started on effective drug treatment. In addition,
the CDC reported that studies in some areas have shown that over 20 % of selected
inner city intravenous drug user populations have tuberculous infection (Ex.
3-37). The CDC thus concluded that drug center clients and staff are at risk
of becoming infected. Employees in drug treatment facilities who may have
occupational exposure include, but are not limited to, counselors, nurses,
physicians and other staff. Work
settings where occupational exposure occurs as a result of the performance of
high-hazard procedures, which, for the purposes of this standard, are certain
procedures performed on individuals with suspected or confirmed infectious
TB, are also covered under the scope of the standard as stated under
paragraph (a)(7). High-hazard procedures are procedures that are
cough-inducing or aerosol-generating that are likely to result in droplet
nuclei being expelled into the air. A definition and discussion of
high-hazard procedures can be found under paragraph (j), Definitions, of this
Summary and Explanation. <<Health care workers>> and other employees who are
either performing or assisting with these procedures or are in the general
vicinity are at an increased risk of inhaling droplet nuclei and therefore
have occupational exposure. The 1994 CDC guidelines recommend in Section G,
"Cough-Inducing and Aerosol-Generating Procedures" that special
precautions be taken when these procedures are performed (Ex. 4B). <<Health care
workers>>,
such as physicians, nurses, technicians and others who perform or assist in
the performance of high-hazard procedures have occupational exposure. Other
employees who may be in the room or area when such procedures are performed
would be expected to have occupational exposure as well. Paragraph
(a)(8) applies to occupational exposure that occurs in laboratories that
handle specimens that may contain M. tuberculosis, process or maintain
those specimens or the resulting cultures, or perform any related activity
that may result in the aerosolization of M. tuberculosis. M.
tuberculosis is a proven hazard to laboratory personnel (Exs. 7-68, 7-72,
7-142, 7-143). Aerosols present the greatest hazard in laboratories. Tubercle
bacilli may be present in sputum, gastric lavage fluids, cerebrospinal fluid,
urine, and in lesions from a variety of tissues. In addition, the bacilli are
grown in culture to increase their concentration beyond what would normally
be found in the sample for purposes of identification and susceptibility
testing. The bacilli may survive in heat-fixed smears and may be aerosolized
in the preparation of frozen sections and during manipulation of liquid
cultures. CDC/NIH's manual "Biosafety in Microbiological and Biomedical
Laboratories" recommends Biosafety Level 2 or 3 for such laboratories
depending on the procedures being performed (Ex. 7-72). Employees who may
have occupational exposure include a wide variety of laboratorians. Examples
include, but are not limited to, medical technologists, laboratory
technicians, physicians, and research scientists. Occupational
exposure incurred by temporary or contract employees is also covered under
the Scope to the extent that the occupational exposure occurs in one of the
work settings listed under paragraphs (a)(1) through (a)(8). For example, if a
nurse working for a temporary employment service were hired by a hospital to
work on a TB ward, that temporary nurse would be covered under the scope of
the standard. Physicians who are employees (e.g., of an independent
corporation) yet who practice and are exposed in a covered facility, such as
a hospital, are also covered by the standard. Similarly, in any of the work
settings listed under paragraph (a)(1), temporary or contract personnel who
incur occupational exposure to TB as a result of their temporary or contract
work would be covered by the standard. The occupational exposure experienced
by these employees would be expected to be similar to that of other employees
performing the same tasks and procedures in the work setting that has
contracted for their services. A note has been added to the proposed standard
to make clear that these types of employees are covered under the scope. This
note also clarifies that repair, replacement, or maintenance personnel,
working in any of the work settings covered under paragraphs (a)(1) through
(a)(8), who service air systems or equipment or who renovate, repair or
maintain areas of buildings that may reasonably be anticipated to contain
aerosolized M. tuberculosis are also covered under the scope of the
standard. The standard requires the use of engineering controls, such as
isolation rooms, to reduce the concentration of droplet nuclei and therefore
reduce the likelihood of TB infection and subsequent illness. The ventilation
systems that exhaust air from isolation rooms may reasonably be anticipated
to contain aerosolized M. tuberculosis. Maintenance and other workers
who are responsible for the servicing and repair of ventilation systems that
handle air that may contain aerosolized M. tuberculosis are at risk for
occupational exposure when, as the result of performing their duties, they
are exposed to TB contaminated air moving through the ventilation system. Examples
of employees who may have occupational exposure include heating, ventilation,
and air conditioning (HVAC) maintenance personnel. In
addition, there may be employees who are responsible for renovating,
repairing, or maintaining areas of buildings where exposure to aerosolized M.
tuberculosis may occur other than those associated with the ventilation systems.
Maintenance staff who need to repair fixtures in an isolation room, or
contractor personnel hired to provide housekeeping in isolation rooms or
areas, are examples of such employees who would also be covered under the
standard. OSHA expects that such exposures would occur only rarely. In many
circumstances, minor non-emergency maintenance activities could be performed
by health care personnel required to enter the isolation rooms or areas for
other reasons, such as to care for a patient. However, there may be
activities that necessitate the expertise of certain maintenance employees
which could place those employees at risk of occupational exposure. Those
employees would therefore be covered under the scope of the standard. Paragraph
(a)(9) applies to occupational exposure occurring during the provision of
social work, social welfare services, teaching, law enforcement or legal
services, where the services are provided in the facilities included in
paragraphs (a)(1) through (a)(8), or in residences, to individuals who are in
AFB isolation, or are segregated or otherwise confined due to having
suspected or confirmed infectious tuberculosis. This paragraph is intended to
cover those types of employees who must provide services to individuals who
have been identified beforehand as having suspected or confirmed infectious
tuberculosis and who have either been isolated or segregated in isolation
rooms or areas or have been confined in their homes. For example, certain
social workers may need to enter AFB isolation rooms or areas or visit homes
of people who have suspected or confirmed infectious tuberculosis for the
purposes of collecting information or providing discharge planning. While
OSHA believes that it would be preferable to collect such information over
the telephone in order to prevent occupational exposure, the Agency realizes
that there may be situations where direct contact with these isolated or
confined individuals may be necessary. In these limited situations, these
employees would be covered under the scope of the standard. There may also be
situations where teachers may be providing tutoring to individuals isolated
with suspected or confirmed infectious tuberculosis. Again, OSHA believes
that such situations would be limited and that most educational instruction
could be delayed until an individual was determined to be noninfectious. However,
where teachers must provide instruction to individuals identified as having
suspected or confirmed infectious TB, those teachers would be covered under the
scope of the standard. In addition, certain law enforcement officers might
have to be in contact with individuals who have been identified as having
suspected or confirmed infectious tuberculosis. For example, they may have to
transfer such an individual from a correctional or detainment facility to a
hospital for diagnosis or treatment. Because these workers must be in direct
contact with the individual during transport, perhaps for long periods of
time and probably in an enclosed vehicle, such employees could incur
significant occupational exposure. Paragraph (a)(9) would assure that such
employees would be covered under the standard. Similarly, there may be
occasions where attorneys must consult with clients or inmates who have been
isolated or segregated because they have been identified as having suspected
or confirmed infectious tuberculosis. Such attorneys would be covered under
the standard in the limited situations where these consultations cannot be
done by phone or delayed until the individual has been determined to be
noninfectious. Under paragraph (a)(9), OSHA has specified certain employee
groups that it believes would have to enter AFB isolation rooms or areas or
homes where individuals are confined due to suspected or confirmed infectious
TB, in order to provide services which may result in occupational exposure. OSHA
requests comments and data as to whether there are other employee groups that
may incur occupational exposure and thus need protection under this
paragraph. Paragraph
(a)(10) applies to occupational exposure occurring during the provision of
emergency medical services, home health care, and home-based hospice care. Emergency
medical service employees may provide emergency treatment and transportation
for individuals with suspected or confirmed tuberculosis. For example, in
addition to serving the same high-risk client population as hospitals,
emergency medical services are often used to transport individuals who have
been identified as having either suspected or confirmed infectious
tuberculosis from a facility with inadequate isolation capabilities to
another facility better equipped to isolate these individuals. Proximity to
the patient and time spent within an ambulance or other emergency vehicle
affects the likelihood of occupational exposure as the result of breathing
droplet nuclei generated when the patient coughs or speaks. Examples of
employees who may have occupational exposure include but are not limited to
emergency medical technicians, paramedics, and, in some localities, fire
fighters. The
1994 CDC guidelines identify <<health care workers>> who provide medical services in
the homes of patients with suspected or confirmed infectious tuberculosis as
being at risk and recommend precautions to be used in these settings (Ex.
4B). Employees who provide home-based care serve a client population similar
to that of hospitals (e.g., individuals who may be immunocompromised).
Employees such as nurses and aides who provide care to these individuals
would be expected to have occupational exposure. OSHA
is also proposing that certain limited construction activities be included
under the scope of the standard; however, the Agency believes that the
proposed standard would have little impact on this sector. The standard would
apply to construction operations occurring in the work settings covered by
the scope of the standard where there is a reasonable anticipation of
exposure to aerosolized M. tuberculosis, e.g., while rebuilding
an HVAC system that would connect to an existing one that is in use. The
standard is not intended to cover employees involved in other construction
operations where they would not have occupational exposure to air which may
reasonably be anticipated to contain aerosolized M. tuberculosis (e.g.,
a crane operator constructing a new wing of a hospital). The standard would
apply only to construction employees who would incur occupational exposure to
tuberculosis. Such a case might arise during maintenance operations on an air
system that carries air that may reasonably be anticipated to contain
aerosolized M. tuberculosis or during renovation, repair, or
alteration of areas of buildings that may reasonably be anticipated to
contain aerosolized M. tuberculosis. The probability of exposure to M.
tuberculosis during these activities may be high and it is necessary,
therefore, for employees performing the work to wear respirators, receive
medical surveillance and be protected by the other provisions of the proposed
TB standard. Employees of such contractors are subject to the same levels of
TB exposure and need the same protection as other exposed employees. Therefore,
OSHA proposes to cover these employees under the TB standard and has included
construction within the standard's scope. Thus,
although the impact of the standard will be limited, OSHA believes that
construction should not be exempted from the proposed standard. OSHA believes
that a loophole would be opened in the enforcement of the standard if
construction were exempted. The distinction between maintenance and
construction is often an ambiguous one. If construction were excluded,
contractors, such as HVAC contractors, might argue that their work is
"construction" and that they are not covered by the standard. By
covering construction, this ambiguity does not arise. This approach is
consistent with that taken in other standards (e.g., Ethylene Oxide,
29 CFR 1910.1047; Benzene, 29 CFR 1910.1028). Several
of the sectors covered by the proposed standard may be utilizing volunteers
for assistance in the workplace. Under the OSH Act, OSHA is mandated to
protect employees against workplace hazards. Consequently, volunteers are not
covered by OSHA standards because they are not employees. However, employers
should be aware that simply labeling a person as a volunteer is not
determinative of whether an employer/employee relationship exists, if the
person is compensated for his or her services. Some states or localities may
decide to extend the protections of OSHA standards to volunteers; however,
such action is the independent decision of these jurisdictions and is not a
requirement of the OSH Act. In
addition, the proposed standard applies in situations when an employer has
part-time employees, or where employees of other employers are working in a
covered facility. These employees are covered by the standard in the same
manner as other employees who have occupational exposure to tuberculosis. For
example, they would be provided with the same protections as full-time on-site
employees, such as being included in the exposure determination, being
trained, being provided with medical surveillance, and being issued
respiratory protection if necessary. With regard to employers who provide
employees to other employers (e.g., personnel providers, temporary
help agencies, nurse registries), a shared responsibility for worker
protection exists between the provider and the client or "host"
employer. The safety and health rights of temporary or "leased" or
contracted employees are the same as the rights of those who are employed
directly by the host employer. The host employer is generally responsible for
safety and health measures taken to address hazards that are an integral part
of the workplace the host employer controls. Where other employers are
involved, contractors or other "providers," a joint
employer-employee relationship may exist in which both (or more) employers
share responsibility for the safety and health of the employees. OSHA's
concern is to assure that workers receive full protection under this
standard. Who provides which protections to the various employees may be
specified as a matter of contract or employment agreement existing between
the client/host and the contractor/provider. In a typical arrangement, for example,
the provider employer might provide the generic training required by the
standard and assure that proper follow-up medical evaluation occurs after an
exposure incident. Host employers would typically control potential exposure
conditions and fulfill other requirements of the standard, such as
site-specific training and respiratory protection. While
the proposed standard covers a number of different work settings, as
described above, OSHA recognizes that many different types of activities
occur in these different settings. Thus, not all provisions of the proposed
standard would apply in each work setting. The provisions that are required
will vary to some degree, depending on the type of activities done in the
work setting. In order to give employers guidance as to what provisions would
be applicable in their work setting, OSHA has developed a series of charts of
the requirements that are most likely to be applicable for the affected
industries. The
following charts outline provisions that would be required for employers
covered under the scope of the proposed TB standard. (Employers who
qualify for the limited program as outlined under Paragraph (b), Application,
should consult Appendix A for applicable provisions.) The charts are
categorized either by the types of infection control activities that may be
common among different work settings (e.g., early identification and
transfer of individuals with suspected or confirmed infectious TB) or by a
particular occupational work group (e.g., emergency medical services,
home health care). These charts are designed to give employers a guide to the
regulatory text by outlining the provisions of the proposed standard that are
applicable for various types of work settings. These charts summarize the
general responsibilities of a particular required provision. The regulatory
text should be consulted for more specific details on particular provisions. In
addition, it should also be kept in mind that even though these charts are
categorized by the type of activities occurring at a worksite, the categories
do not necessarily always follow industry lines (i.e., an employer under a
specific industry sector may not always fall under a particular category
outlined in the following charts). The charts are not designed to serve as a
stand alone check list for any one industry sector. Due to the varying
activities that may take place in work settings encompassed by an industry
sector, the charts may not account for every applicable provision in every
work setting. The charts are intended to provide general guidance as to what
OSHA anticipates to be applicable provisions. Therefore, it is important that
employers evaluate the types of activities occurring in settings where their
employees work to determine which of the provisions of the proposed standard
would be applicable. In order to give employers guidance, OSHA has listed
some of the types of industry sectors that the Agency assumes are likely to
fall under a particular category, given OSHA's current understanding of the
activities commonly occurring in these work settings. OSHA
requests comments on these assumptions and on the charts, and particularly,
on how the charts can be made more user friendly and be better organized to
help serve as a guide for employers trying to comply with the standard. The
following charts are included: Chart 1:
What Would Be Required in Work Settings Where Individuals with Suspected or
Confirmed Infectious TB are Admitted or Provided Medical Services? Chart 2:
What Would Be Required in Work Settings Where Early Identification and
Transfer Procedures are Used for Individuals with Suspected or Confirmed
Infectious TB? Chart 3:
What Would Be Required for Employers with Employees Who Provide Services to
Individuals Who Have Been Isolated or Otherwise Confined Due to Having
Suspected or Confirmed Infectious TB or Who Work in Areas Where the Air Has
Been Identified As Reasonably Anticipated to Contain Aerosolized M.
tuberculosis? Chart 4:
What Would Be Required for Home Health Care and Home-Based Hospice Care? Chart 5:
What Would Be Required for Emergency Medical Services? Chart 6:
What Would Be Required for Clinical and Research Laboratories? Chart 7:
What Would Be Required for Personnel Services? Chart
1: What Would Be Required in Work Settings Where Individuals with
Suspected or Confirmed Infectious TB Are Admitted or Provided Medical
Services? OSHA
anticipates that Hospitals will be the primary type of facility falling under
this category. In general, individuals requiring isolation are transferred to
hospitals that have isolation capabilities. In addition, medical services
such as diagnostic testing for evaluating TB disease are performed in a
hospital setting. This category also covers work settings where high-hazard
procedures are performed, e.g., medical examiners' offices. (Laboratories
are covered in a later chart). However, there may be other work settings such
as correctional facilities or long-term care facilities for the elderly that
provide isolation or perform high-hazard procedures on individuals with
suspected or confirmed infectious TB. In these cases, employers at these
facilities would be required to comply with the provisions outlined in this
chart. Chart 7: What Would Be Required for Personnel Services? This
category covers employers who provide temporary employees to any of the other
employers covered under the scope of the standard (e.g., temporary
nurses hired to work at a hospital, temporary lab technicians working in a
clinical laboratory). Employees in these situations are covered by the
standard in the same manner as other employees who have occupational exposure
to tuberculosis. A shared responsibility for worker protection exists between
the personnel service employer and the client (or "host") employer.
These matters may be specified as a matter of contract or employment
agreement existing between the personnel service employer and the host
employer. In this chart OSHA has assumed that a typical contract or
employment agreement exists between the two employers with the personnel
provider accepting responsibility for the general requirements and the host
employer being responsible for site-specific measures. Therefore, the
personnel service provider is shown complying with non-site specific
provisions such as exposure determination, medical surveillance, and non-site
specific employee training. The host employer would comply with more
site-specific provisions such as procedures for early ID, engineering
controls and site-specific employee training. In addition, the chart assumes
that the personnel service provider has accepted the responsibility for
respiratory protection. OSHA requires that workers in these situations
receive full protection under the standard. OSHA's
preliminary conclusion is that all employees who have occupational exposure
to aerosolized M. tuberculosis, as a result of performing their
duties, are at risk of infection. Under paragraph (a) the Agency has listed
those facilities, work settings and services where it believes that
significant occupational exposure is most likely to occur. OSHA requests
comment and supporting data as to whether there are other work settings or
services where significant occupational exposures can be reasonably
anticipated. Paragraph (b) Application As
discussed above, OSHA has preliminarily determined that there are elevated
risks of TB infection associated with certain types of work settings and
services. However, the Agency realizes that there may be employers covered
under the scope of the standard who have work settings in counties where the
risk of TB infection is low. Some geographical areas in the U.S. have not
reported cases of TB to CDC and facilities in these areas have not
encountered any individuals with confirmed infectious TB in their work
settings within the recent past. In
consideration of the lessened likelihood of employee exposure in these work
settings, OSHA is proposing that some employers be permitted to qualify for a
more limited program. Paragraph (b), Application, states that an employer
covered under paragraph (a), Scope, other than the operator of a laboratory,
may choose to comply only with the provisions of Appendix A if the Exposure
Control Plan demonstrates that his or her facility or work setting: (1) does
not admit or provide medical services to individuals with suspected or
confirmed infectious TB; (2) has not encountered a case of confirmed
infectious TB in the past 12 months; and (3) is located in a county that, in
the past 2 years, has had no cases of confirmed infectious TB reported in one
year and fewer than 6 cases of confirmed infectious TB reported in the other
year. Thus, in the past two year period, the number of reported TB cases must
be 0 for at least one of the two years. (It may even be zero for both years).
In the other year, the number of cases must be no greater than 5. For
example, if in the first year of the preceding two- year period the number of
reported cases was 0, but in the second year there were 4 reported cases of
confirmed infectious TB in the county, an employer would still qualify for
the limited program under paragraph (b), provided that none of the cases were
encountered in his or her employees' work setting. However, for the employer
in this scenario to continue to qualify for the limited program, the number
of cases reported in the third year would have to return to zero. Similarly,
employers would not qualify for the limited program if the number of cases of
confirmed infectious TB reported in the county was greater than zero in both
of the preceding two years or if 6 or more cases were reported in one of the
preceding two years. OSHA
has taken this approach because the number of TB cases fluctuates widely and
different locations and geographical areas may be affected at different
times. For example, many counties report no cases in one year or even in two
consecutive years, or report a few cases in one year but then have no cases
in the following year. From 1992 to 1994 (Ex.7-262), 55.3 percent of the
counties in the U.S., representing 12.9 percent of the population, reported
no confirmed cases of TB in one year of the preceding two-year period and
fewer than 6 cases in the other year. OSHA believes that the approach
described above is appropriate given these fluctuations and that it reduces
the burden on employers who rarely encounter TB cases by allowing them to
qualify for the limited program. OSHA initially considered allowing employers
to qualify for the limited program only if there had been no cases of
confirmed infectious TB reported in the county in the preceding one-year
period. This would have meant that an employer would be required to comply
with the full program if even a single case was reported in the county in any
year. OSHA requests comment on the approach taken in the proposed rule and
the appropriateness of the "zero-county" trigger used in the
standard. Although
OSHA believes that the risk of incurring TB is substantially reduced in
facilities located in counties qualifying for the limited program, the risk
of infection continues because all counties have residents who are infected
and who may therefore develop active TB and transmit it. In addition, the
mobility of the U.S. population means that it is easy to carry the disease
from higher risk areas to lower risk areas. Thus, OSHA believes that certain
TB exposure control provisions, i.e., those reflected in the limited program
required by the standard, need to be in place in all work settings where
cases of TB could be encountered. Under
the limited program, employers are responsible for (1) preparing a written
exposure control plan with certain minimal elements, (2) providing a baseline
skin test and medical history, (3) making medical management and follow-up
available after an exposure incident, (4) providing medical removal
protection if necessary, (5) providing information and training to employees
with potential occupational exposure, and (6) complying with pertinent
recordkeeping requirements. The specific paragraphs of the proposed standard
that would apply in these situations are outlined in Appendix A. OSHA
believes that these provisions are the minimum requirements necessary for
employee protection, even in work settings where no TB has recently been
reported in the county and no individuals with confirmed infectious TB have
been encountered within the work setting during the past 12 months. OSHA's
reasoning is that, although no cases of confirmed infectious TB have been
reported for the preceding two years, there is considerable fluctuation among
counties from one year to the next, as explained above. In addition, as
discussed in the preliminary risk assessment section of the preamble, there
is a high prevalence of TB infection nationwide, approximately 6.5 percent. Infections
may become active after a latency period of years. Therefore, the absence of
a reported active case in the immediate past does not mean that active cases
will not be manifested in the current or subsequent years. For these reasons,
it is necessary for covered facilities to maintain, at a minimum, a TB
program that incorporates the basic TB exposure control provisions that will
protect employees from exposures. A
primary element of the limited program is a written exposure control plan. The
exposure control plan includes an exposure determination to identify those
employees who would incur occupational exposure if an individual with
infectious TB were encountered in the work setting. The exposure control plan
would also have to contain procedures and policies for the early
identification and masking of individuals with suspected or confirmed
infectious TB and procedures for transferring those individuals to other
facilities. This would assure that if an individual with suspected or
confirmed infectious TB were to enter the workplace, he or she would be
promptly identified and transferred to a facility with AFB isolation
capabilities. In addition, while awaiting transfer, these individuals could
be masked to the extent that it is feasible (e.g., in the case of a
non-combative individual) in order to prevent transmission. Similarly, the
exposure control plan must include procedures for reporting exposure
incidents should they occur. Employees need to know what steps to take if an
exposure occurs so that appropriate follow-up can be initiated for the
medical management of the exposed employee and investigation of the incident. In
order to qualify for the limited program pursuant to paragraph (b), the
employer must include in his or her exposure control plan the number of TB
cases reported in the county and the number of individuals with confirmed
infectious TB who have been encountered within the work setting. An employer
is required by the standard to check and document the number of confirmed
infectious TB cases in the county once a year. Typically, county health
departments collect this information for reporting purposes and report it
both on a monthly and an annual basis. Obtaining the annual count from the
county health department would meet the requirements of the proposed rule. County
case counts must be recorded for the two most recent annual reporting
periods, i.e., the two preceding years. This count must be reflected in the
employer's Exposure Control Plan, as described below in paragraph (c),
Exposure Control Plan, of this Summary and Explanation. The count of cases
and the notation in the Plan can be kept in any media, e.g., paper or
electronic. In
addition to an abbreviated exposure control plan, the limited program would
include some of the basic elements of medical surveillance, i.e., baseline
skin tests and medical histories for employees identified under the exposure
determination and medical management and follow-up for those employees who
have had an exposure incident. Baseline skin tests and histories will help to
assure that true conversions are appropriately identified should an exposure
incident occur. Medical management and follow-up provisions will assure that
exposed employees receive the proper medical evaluation after an exposure
incident and that the incident is properly investigated so that it will not
occur again. Under this limited program, no periodic medical surveillance
would be required. Where
necessary, the employer is also required to provide medical removal and
protection (MRP) of benefits for those employees who develop active TB. OSHA
anticipates that the need to provide MRP would be a rare event because little
active TB has been reported in many of these counties. In addition, if
employees are properly trained to identify suspected and confirmed infectious
TB and to promptly transfer those individuals, few occupational exposures
should occur, thus minimizing the likelihood that employees will become
infected. Therefore, training is an important element of the limited program.
Training is a key element in assuring that employees know how to identify
individuals with suspected or confirmed infectious TB and the necessary steps
to take if such an individual is encountered. Certain
minimal records must also be kept by the employer. Medical records for
documenting baseline skin tests and any potential medical evaluations made as
a result of an exposure incident, as well as records for training and records
for OSHA illnesses and injuries, would have to be kept. Keeping records
should not be burdensome for the employer since it is likely that only a
minimal number of employees would be identified by the exposure determination
as having potential occupational exposure (e.g., intake workers in
admitting areas or emergency departments); only such employees need medical
surveillance or training. The
elements of the limited program outlined under this paragraph closely track
the recommendations of the CDC for facilities designated as having
"minimal risk" under the CDC's TB Guidelines for Health Care
Facilities (Ex. 4B). Under these guidelines, CDC considers facilities to have
"minimal risk" if there is no TB in the community and no TB in the
facility. CDC's recommendations for such facilities include a written TB
control plan, procedures for early identification and prompt transfer of
individuals with suspected or confirmed infectious TB, and employee training.
CDC does not specifically recommend baseline skin testing. However, CDC's
guidelines do say that baseline testing would be advisable in these
facilities so that, if an unexpected exposure does occur, conversions can be
distinguished from positive skin test results caused by previous exposures. CDC
also recommends that a risk assessment be conducted by such facilities each
year. In the case of a "minimal risk" facility, as defined by CDC,
this would essentially involve checking on the number of reported cases of TB
in the community and within the facility, which is essentially what OSHA
requires under the exposure control plan as documentation to qualify for the
limited program available under paragraph (b). Paragraph
(c) Exposure Control Employees
incur risk each time they are exposed to aerosolized M. tuberculosis. A
worker can become infected from a single exposure incident, and thus it is
necessary to prevent exposure incidents whenever possible. The goal of this
proposed standard is to reduce the significant risk of infection by
minimizing or eliminating occupational exposure to aerosolized M. tuberculosis. One
purpose of paragraph (c), Exposure Control, is to identify the tasks and
procedures where occupational exposure may occur and to identify those
employees whose duties include these tasks and procedures. An additional
purpose of the paragraph is to develop and document, in an exposure control
plan, policies and procedures for eliminating or minimizing occupational
exposure, e.g., developing procedures for identifying individuals with
suspected or confirmed TB, for appropriately isolating and minimizing
employee contact with those individuals, and for reporting exposure
incidents. Paragraph
(c)(1) requires each employer who has an employee with occupational exposure
to prepare an exposure determination that identifies those employees who have
occupational exposure to aerosolized M. tuberculosis. As discussed
under paragraph (j), Definitions, "occupational exposure" means
"reasonably anticipated contact that results from the performance of an
employee's duties, with an individual with suspected or confirmed infectious
TB or air that may contain aerosolized M. tuberculosis." Thus,
the exposure determination needs to include, in addition to those employees
who have direct contact with individuals with suspected or confirmed
infectious TB and employees who perform procedures that may aerosolize M.
tuberculosis, those employees who can reasonably be anticipated as part
of their job duties to be exposed to air that may contain aerosolized M.
tuberculosis. For
example, while an admissions clerk in a homeless shelter will not perform
medical procedures on a client with suspected infectious tuberculosis, the
clerk may reasonably be anticipated to encounter and share the same airspace
with such an individual. Therefore, the admissions clerk would be included in
the Exposure Control Plan and would be covered by this standard. Exposure
determination is a key provision of exposure control because the employer
must know which tasks or procedures involve occupational exposure in order to
determine what measures can be taken to eliminate or minimize exposure
incidents. In addition, an exposure determination is necessary in order to
ascertain which employees are to be provided with respiratory protection,
medical surveillance, and training. Each
employer is required to consider the duties, tasks, and procedures of all
employees in each job classification in each work area where occupational
exposure occurs when making the exposure determination. OSHA believes that it
is appropriate to allow the employer to identify and document job
classifications where all or some employees have occupational exposure as a
basis for the required exposure determination. By identifying the job
classification, each employee included in the description will know that he
or she is within the scope of the standard. Listing of every employee's name
is not required, however, because that may be burdensome for employers who
have many employees with occupational exposure. The
term "job classification" is used generically. During the
development of the Bloodborne Pathogens standard, commenters used several
terms (e.g., "job category", "job responsibility",
"job title", "position description") to identify and
document employees at risk in the exposure determination. OSHA sought to use
a term that would encompass all of these terms. Therefore, as in the
Bloodborne Pathogens standard, OSHA has chosen to use the term "job
classification" because it has the broadest application to facilities of
all sizes that use formal and less formal designations to classify employees.
Thus, the standard would allow employers to use existing job titles, job
descriptions, or other designations to identify those job classifications in
which occupational exposure occurs. OSHA solicits comment on whether this
term needs further defining in this paragraph or in paragraph (j),
Definitions. The
standard does not require that every task and procedure that could result in
occupational exposure be listed in the exposure control plan, but instead
gives the employer a choice in how to document the exposure determination. Paragraph
(c)(1)(i) states that the exposure determination shall contain: (A)
A list of the job classifications in which all employees have occupational
exposure; and (B)
A list of the job classifications in which some employees have occupational
exposure, and a list of all tasks and procedures (or groups of closely
related tasks and procedures) that these employees perform and that involve
occupational exposure. This
means that the employer may choose to extend "blanket" coverage to
those job classifications where essentially all employees have occupational
exposure [the paragraph (c)(1)(i)(A) option]. In this case, the employer
would not have to list all tasks and procedures for those employees in the
exposure control plan, since all of these employees would be covered by the
standard. For example, if a hospital determines that all employees within the
job classification "respiratory therapist" have duties or
responsibilities that involve tasks and procedures where occupational
exposure occurs, the job classification "respiratory therapist" can
simply be listed in the exposure determination in accordance with paragraph
(c)(1)(i)(A) and no subsequent listing of those tasks and procedures is
required. Similarly, the job classification of "homeless shelter
admissions clerk" in the previous example could be included under the
"blanket" job classification list in paragraph (c)(1)(i)(A). On
the other hand, the employer may determine that job classifications exist in
which only some employees have occupational exposure. The employer may
determine that it is not necessary to include all employees in such job
classifications under the standard since only a portion of them have
occupational exposure. In these situations [paragraph (c)(1)(i)(B)], the
employer must list the job classification as well as the tasks and procedures
or groups of closely related tasks and procedures performed by employees
within that job classification that result in occupational exposure. For
example, within the job classification "laboratory technician,"
there may be some employees who experience occupational exposure (e.g.,
laboratory technicians who perform microbiological procedures on M.
tuberculosis cultures), while others would not be expected to have such
exposure (e.g., laboratory technicians who work in clinical
chemistry). In such a case, the employer may not wish to extend coverage to
all employees in the job classification "laboratory technician". Consequently,
the job classification "laboratory technician" would be listed in
the exposure determination along with the tasks and procedures in which
occupational exposure occurs. This approach would inform employees within the
job classification "laboratory technician" about those tasks that
they perform that involve occupational exposure and that employees performing
those tasks and procedures triggers their inclusion in the scope of the
standard. However, it would not be necessary for the employer to list each
procedure performed by a "laboratory technician". For example,
performing sputum smears, culturing the bacteria in the sputum, and
conducting drug-susceptibility testing on the culture all involve
manipulation of specimens that could contain M. tuberculosis. Therefore,
these tasks could be grouped under the designation "manipulation of
specimens that may contain M. tuberculosis." Although
the standard permits the exposure determination to list job classifications,
grouping job classifications according to location would not be sufficient to
meet the requirement for identifying job classifications with occupational
exposure. For example, identifying job classifications by using the
"Emergency Department" would not fulfill this requirement because
it does not identify the specific employee job classifications that have
occupational exposure. An employer who has determined that employees in the
"Emergency Department" warrant coverage under the standard would
have to list the job classifications that involve occupational exposure and
identify the tasks and procedures that result in occupational exposure. OSHA
believes that merely grouping employees by location, e.g., designating
all employees who work in the Emergency Department, may exclude employees who
have occupational exposure since such a grouping could overlook employees who
may occasionally enter the Emergency Department but are not routinely
assigned there. OSHA seeks comment about the protectiveness of permitting
exposure determinations to be made by location within a work setting in
certain specific instances where the employer believes such a delineation is
useful and will not misclassify employees and specifically requests examples
of regulatory language that could achieve these objectives. Paragraph
(c)(1)(ii) requires that the exposure determination be made without regard to
the use of respiratory protection. It has been OSHA's long-standing position
that the determination of occupational exposure be made without regard to the
use of personal protective equipment such as respirators. The reason for this
is that several conditions must be met for respiratory protection to
effectively lessen exposures. First, the employee must be trained to use the
equipment properly. Second, respiratory protection must be used each time the
task requiring such protection is performed. Third, respiratory protection
must fit properly. If even one of these conditions is not fully met,
protection cannot be assured. Therefore, all tasks that entail occupational
exposure need to be included in the exposure determination, regardless of the
use of respiratory protection. This approach is consistent with other OSHA
standards (e.g., Bloodborne Pathogens, 29 CFR 1910.1030; Formaldehyde,
29 CFR 1910.1048; Cadmium, 29 CFR 1910.1027) and is essential to designing an
appropriate exposure control program. Utilizing this approach assures that
workers who perform tasks requiring respiratory protection will receive the
training, medical surveillance, and other provisions of this standard that
will enhance their safety should respiratory protection fail. Paragraph
(c)(2) requires that each employer covered under the scope of the standard
establish a written exposure control plan. The exposure control plan is a key
provision of the standard because it requires the employer to identify the
employees who receive training, respiratory protection and medical
surveillance and to develop a number of policies and procedures that will
eliminate or minimize employees' exposure to sources of aerosolized M.
tuberculosis. However, because not all employers' work settings are the
same, not all employers' exposure control plans will need to contain the same
elements. The goal of the exposure control plan is to address the type of
exposure that occurs in a given work setting, as identified under the exposure
determination, and then to develop procedures and policies to minimize or
eliminate that exposure. Thus, the size and complexity of the exposure
control plan will be relative to the types of exposure encountered in the
employer's work setting. For example, social service employees who must
provide services to individuals who are in AFB isolation are covered under
the scope of the standard. The employer in this case would only have to
include certain minimal elements in his or her exposure control plan. This
employer would not have to include elements for identifying individuals with
suspected or confirmed infectious TB since these individuals will already
have been identified by someone else. Similarly, the exposure control plan of
such employers would not have to include procedures for isolating or managing
the care of individuals with infectious TB. On the other hand, hospitals that
admit or provide medical services to individuals with suspected or confirmed
infectious TB would be required to have a more extensive exposure control
plan since the employer in this case would be responsible for identifying,
isolating and possibly performing high-hazard procedures on individuals with
suspected or confirmed infectious TB. Under
paragraph (c)(2)(i), the proposed standard requires that the exposure control
plan be written. There are several reasons for having the plan in writing. First,
because exposure control must be practiced by everyone -- employee and
employer -- it is imperative that an employee be able to find out what
provisions are in place in his or her workplace. In addition, the exposure
determination gives an employee who may be unfamiliar with the job a ready
reference for ascertaining which job classifications, tasks, and procedures
entail occupational exposure. Second, the exposure control plan also serves
as an on-site adjunct to the overall infection control plan for the work
setting and reinforces the employer's training program. Employees will be
trained about the various procedures developed by the employer to eliminate
and minimize exposure. Having the procedures written and available at the
work site will provide a ready reference for employees and will serve as an
adjunct to their training. Third, having the plan in writing is also important
for enforcement purposes. By reviewing the exposure control plan, an OSHA
compliance officer will be able to become familiar with the employer's
determination of tasks and procedures with occupational exposure, the job
classifications whose duties include those identified tasks, and the policies
and procedures the employer uses to minimize occupational exposure along with
any revisions to the exposure control plan. OSHA
realizes that many workplaces covered under the scope of the proposed
standard may already have comprehensive infection control plans that may
include many of the measures required by the proposed standard. It is not
OSHA's intent for employers to duplicate current infection control plans
solely for the purpose of complying with the standard. Therefore, the
exposure control plan may be comprised of existing documents that are part of
a larger infection control plan. However, all elements of the exposure
control plan for TB required by the proposed standard must be included. In
addition, the plan must be in some manner a cohesive entity by itself or a
guidance document must exist that states the overall policy goals and directs
the reader to the location of the separate documents that are being used to
fulfill the requirements of the standard. While
there will be differences in the elements of employers' exposure control
plans, each employer covered under the scope of the standard must have
certain minimal elements in his or her plan. Paragraphs (c)(2)(i)(A) through
(c)(2)(i)(C) contain the minimal elements that must be included in the
exposure control plans of every employer covered under the scope of the
standard. Paragraph (c)(2)(i)(A) requires that the exposure control plan must
include the exposure determination required under paragraph (c)(1). As
discussed above, the exposure determination is necessary to identify those
employees who have occupational exposure so that the employer can determine
which employees are to be given respiratory protection, medical surveillance
and training. Paragraph
(c)(2)(i)(B) requires that the employer develop procedures for informing
occupationally exposed employees about suspected or confirmed infectious TB
cases and about air that may reasonably be anticipated to contain aerosolized
M. tuberculosis in order that the employees can take proper
precautions against M. tuberculosis exposure. Once individuals with
suspected or confirmed infectious tuberculosis have been identified, it is
necessary to convey this information to employees who may be exposed so that
they may take the steps necessary to eliminate or minimize their exposure. When
patient confidentiality may be a concern, it is not necessary to use an
individual's name to satisfy this provision. For example, lists do not need
to be made of all patients in the hospital with active TB. Information may be
conveyed to employees by simply labeling the isolation room with the warning
sign required under paragraph (h)(2)(iii) while the room is in use for TB
isolation. Labeling the room will inform the employees that the individual in
the room is in respiratory isolation and the employee must stay out of the
room or don the appropriate respiratory protection before entering. Another
scenario in which such notification is necessary would be when such an
individual must be transported to another facility in an ambulance. In this
case, the employees who will be present in the ambulance would have to be
notified so that they could utilize proper precautions during the transport. Paragraph
(c)(2)(i)(C) requires that the employer include in the exposure control plan
procedures for reporting exposure incidents, including identification of the
person to whom the incident is to be reported, and the procedures the
employer will use for evaluating the circumstances surrounding exposure
incidents as required by paragraph (g)(4)(iv). Under paragraph (j),
Definitions, an exposure incident * * * is defined as *
* * an event in which an employee has been exposed to an individual with
confirmed infectious TB or to air containing aerosolized M. tuberculosis
without the benefit of all applicable exposure control measures required by
this section. In
the event that unprotected employees are exposed to aerosolized M.
tuberculosis, it is necessary that this exposure incident be reported to the
employer as soon as feasible in order to promptly initiate proper medical
management and follow-up of the exposed employee. In addition, quick
reporting of exposure incidents permits the employer to investigate the
circumstances surrounding such incidents while pertinent conditions remain
relatively unchanged and are fresh in the employee's memory. Procedures
need to be in place describing how the exposure incident is to be
investigated. Having investigation procedures in place beforehand will help
to assure that such investigations are able to be done promptly and in a
consistent and thorough manner from case to case. This will assist the
employer in complying with the requirement of paragraph (g)(4)(iv) that
directs the employer to investigate and document the circumstances
surrounding the exposure incident to determine if changes can be instituted
that will prevent similar occurrences in the future. Paragraph
(c)(2)(ii) applies to employers who transfer individuals with suspected or
confirmed infectious TB to a facility with AFB isolation capabilities. This
would apply to employers who operate a facility from which an individual with
suspected or confirmed infectious TB is transferred and would not apply to
employers whose employees provide certain services such as social welfare
services to individuals who have been isolated and in settings where home
health care and home hospice care is provided. The
standard does not require any employer to transfer individuals with suspected
or confirmed infectious TB. Transfer is an option that employers have that
relieves the employer of many provisions of the standard, such as AFB
isolation rooms. If an employer chooses to use the transfer option, the
employer must include the procedure for implementing the transfer in the
exposure control plan. Paragraph
(c)(2)(ii) requires employers who transfer individuals with suspected or
confirmed infectious TB to develop exposure control plan procedures that
address the following: (1) prompt identification of individuals with
suspected or confirmed infectious TB; (2) masking or segregation of
individuals with suspected or confirmed infectious TB; and (3) transfer of
such individuals to a facility with AFB isolation capabilities. One
of the most important steps in preventing TB transmission is the early
detection of individuals who may have infectious TB (Exs. 3-33, 3-34, 3-35,
4B). It is essential that individuals with suspected or confirmed infectious
TB be identified as soon as possible so that employees who must have contact
with them will be warned early and be able to use appropriate infection
control practices to protect themselves from exposure. Obviously, the sooner
this is done, the less occupational exposure there will be and the less
likely that TB will be transmitted. In addition, early identification of
individuals with suspected or confirmed infectious TB will allow for the
timely transfer and initiation of effective treatment of those individuals
for whom the diagnosis of TB is likely. By promptly administering effective
treatment, these individuals can be rendered noninfectious, thus decreasing
the time they are infectious and their potential for exposing employees and
other people. OSHA
is proposing that employers develop a procedure for the prompt identification
of individuals with suspected or confirmed infectious TB as part of the
exposure control plan. In order to assure prompt identification, it is
necessary for the employer to have procedures in place regarding how this
identification will be made. CDC has recommended that identification
procedures be based on the prevalence and characteristics of TB in the
population served by the specific facility (Ex. 4B). For example, individuals
who come from communities with a high prevalence of TB and exhibit certain signs
of TB may be more highly suspected as having infectious TB than individuals
from communities with a low prevalence of TB. OSHA, therefore, expects that
the procedures may be different depending upon the local conditions. The
procedure needs to contain the following: Methodology
-- The employer must describe how he or she will make the determination that
an individual should be considered as having suspected or confirmed
infectious TB. There are several ways of doing this. The employer can use
information provided by a physician or other health care provider in advance
of an individual's admission to the employer's facility that the individual
has been diagnosed with suspected or confirmed infectious TB. If this is not
available the employer must determine whether an individual should be
considered as having suspected infectious TB. OSHA defines suspected
infectious TB as: *
* * a potential disease state in which an individual is known, or with
reasonable diligence should be known, by the employer to have one or more of
the following conditions, unless the individual's condition has been
medically determined to result from a cause other than TB: (1) to be infected
with M. tuberculosis and to have the signs or symptoms of TB; (2) to
have a positive acid-fast bacilli (AFB) smear; or (3) to have a persistent
cough lasting 3 or more weeks and two or more symptoms of TB, e.g.,
bloody sputum, night sweats, anorexia, weight loss and fever. An individual
with suspected infectious TB has neither confirmed infectious TB nor has he
or she been medically determined to be noninfectious. Although
the definition specifies the criteria the employer must incorporate in his or
her plan, the employer will still need to exercise judgment in determining
whether an individual meets one or more prongs of the definition. Of course,
an employer, such as one who operates a facility in an area of particularly
high TB prevalence, is free to use more stringent (i.e., additional) criteria
for considering an individual to have suspected infectious TB in his or her
particular work setting. In
situations where a medical diagnosis is not available either before or at the
time of admission, an employer must collect the information he or she needs
to make the determination. This can be accomplished in two ways. The employer
can have an employee administer a medical history questionnaire to
individuals seeking services from the facility. Another way to obtain
information to make this determination is by having an employee observe the
individual to ascertain his or her health status, looking for the signs, and
asking about the symptoms included in OSHA's definition that may indicate
infectious TB. Many employers will use both questionnaires and observation. The
employee collecting the information will have to be trained on how to conduct
the investigation effectively and with respect for the privacy of the
individual. Responsibilities
-- The employer must designate responsibilities for determining whether an
individual should be considered as having suspected or confirmed infectious
TB. However, all employees need to be given clear instructions regarding
their roles in the prompt identification of suspected or confirmed infectious
TB cases. For example, the <<health care workers>> who are the first points of
contact in ambulatory care settings and emergency rooms in hospitals could be
involved with the initial screening of patients. They may be given several
questions to ask a patient, which would be used as information to begin the
determination. The next actions would depend upon the responses, and the
authority of the <<health care workers>>. Some employees, for example, would only
report answers to questions or their observation of signs of infectious TB in
the client population to someone more knowledgeable. Other employees would be
making determinations. The hospital would probably have a different procedure
that would be used before or at admission to the hospital for scheduled
services. The same hospital might have still another procedure designating
responsibility to other employees for identifying patients who develop TB
while in the hospital. The Exposure Control Plan must designate those
employees who make the determination as to whether an individual has
suspected or confirmed infectious TB. An employer should consider such
designation(s) carefully because, regardless of who determines that an
individual has suspected infectious TB, it is the employer who is responsible
for ensuring that the employee knows and uses the proper criteria. The
identification procedures will likely vary among establishments, depending
upon the type of work done in the facility. For example, facilities that provide
long-term care for the elderly will likely have a different procedure from
hospitals that have an open admissions policy. OSHA also expects that the
methods different employers use may vary depending on whether the employer is
in an area of high or low TB prevalence. This approach is consistent with CDC
recommendations. Promptness
-- Prompt identification of an individual with suspected or confirmed
infectious TB is important because it allows isolation before the disease is
spread through the facility. CDC recommends that procedures be in place for
prompt identification. However, OSHA expects that the determination will be
made as soon as reasonably practical since an employer cannot always make
such a determination immediately. For many situations, such as those
occurring in a hospice, the employer will have information regarding an
individual's health status prior to admitting the individual to the facility.
The employer can use this information to determine whether the individual
should be considered as having suspected or confirmed infectious TB. In a
long-term health care facility, the employer needs to be continually aware of
each resident's health status because it can change rapidly. Information
regarding the signs or symptoms suspected infectious TB needs to be reported
and processed as soon as possible. Effectiveness
-- OSHA believes that an effective procedure, when implemented, will identify
individuals as having suspected or confirmed infectious TB. OSHA believes
that many employers affected by this proposed standard currently use
effective procedures and find them to be practical. However, OSHA also
recognizes that it will not be possible to ensure that the identification
procedure will promptly detect all individuals with infectious TB each time. In
homeless shelters, for example, the clients may withhold information
requested in a questionnaire because they believe that such information may
persuade the shelter to refuse to admit them. Therefore, homeless shelters
may have to place greater reliance on observation of the residents for the
cluster of signs and symptoms associated with infectious TB. Although this
standard would require that homeless shelter workers and others be trained to
look for signs in individuals, it is unlikely that all cases will be
identified. However, if the employer finds that individuals with suspected
and confirmed infectious TB are not being identified, the employer must
investigate in order to determine what procedures need to be modified. During
an inspection, an OSHA compliance officer will review the adequacy of the
procedures, and although a citation would not be issued solely on the basis
of failure to identify an individual with suspected infectious TB because no
identification system is fool-proof, failure to identify a number of
individuals with undetected suspected or confirmed infectious TB would be
good evidence that the procedures or their implementation need to be
investigated and improved and could result in a citation. The
employer must also include in the exposure control plan procedures for
transferring individuals with suspected or confirmed infectious TB to
facilities with AFB isolation capabilities. The procedures must address how
those transfers are to take place in order that the transfers may be
conducted promptly and with minimal exposure to employees. Specifically, they
will include where the cases are to be transferred, how the transfer will
occur, and what precautions employees are to take while individuals with
suspected or confirmed TB are awaiting transfer. As
the note to paragraph (c)(2)(ii) states, an employer's duties regarding
transfer of an individual with suspected or confirmed infectious TB will vary
with the type of facility the employer operates and the work performed by his
or her employees. For example, the transfer responsibilities of hospitals,
long-term care for the elderly, correctional facilities, and hospices may
include contacting the receiving facility, providing transport, and taking
other steps to ensure the individual can get to the receiving facility. These
types of facilities often exercise custodial care over such individuals and,
hence, have more responsibility for assuring completion of the transfer. Conversely,
the responsibilities a homeless shelter or a facility that offers drug
treatment for drug abuse, but that does not have custody over individuals,
may only include providing information about the receiving facility,
contacting the facility, and providing directions to the facility. An
employer who provides home health care or home-based hospice care has no
obligation to transfer an individual from his or her home to a receiving
facility. Transferring an individual with suspected or confirmed infectious
TB protects employees within the facility by making sure the source of
occupational exposure is removed and, of course, benefits the individual in
that he or she receives help in locating and getting to a receiving facility
with the capability for appropriately managing their care. Paragraph
(c)(2)(iii) outlines the additional elements required of employers who have
work settings where individuals with suspected or confirmed infectious TB are
admitted or provided with medical services. Paragraph (c)(2)(iii)(A) requires
that their exposure control plans include procedures for the prompt
identification of individuals with suspected or confirmed infectious TB. As
discussed above, the early identification of individuals with infectious TB
will help to assure that employees who must have contact with those
individuals will be warned early and be able to use appropriate infection
control practices to protect themselves from exposure. In addition, for
employers who have facilities where individuals with suspected or confirmed
infectious TB are admitted and provided medical services, prompt
identification is essential so that isolation precautions and effective
treatment can be initiated as soon as possible, thereby reducing exposure to
employees and other people. Paragraph
(c)(2)(iii)(B) requires that the employer develop procedures for isolating
and managing the care of individuals with suspected or confirmed infectious
TB. Having isolation procedures in place will help to assure that employees
are aware of the steps to take in the event that individuals with suspected or
confirmed infectious TB are identified. If employees know the proper
procedures to follow, they will be better equipped to initiate isolation
promptly, thereby reducing the likelihood that individuals with infectious TB
will infect others. This provision is in accordance with the most recent CDC
guidelines, which also recommend the procedures include: (1)
The indications for isolation, (2) who is authorized to initiate and
discontinue isolation, (3) isolation practices, (4) monitoring of isolation,
(5) management of patients who will not comply with isolation practices, and
(6) criteria for discontinuing isolation. (Ex. 4B) While
OSHA allows the employer to determine what criteria should be included in the
procedures to isolate, the Agency believes that it is prudent for the
employer also to consider the elements listed in the CDC guidelines. Paragraph
(c)(2)(iii)(B) also requires that the employer develop policies and
procedures for managing the care of individuals with suspected or confirmed
infectious TB once they have been placed in isolation. The exposure control
plan must include procedures and polices addressing: (1) Minimization of the
time an individual with suspected or confirmed infectious TB remains outside
of an AFB isolation room or area, (2) minimization of employee exposure in
AFB isolation rooms or areas, (3) delay of elective transport or relocation
of individuals with infectious TB within the facility and, to the extent
feasible, performance of services or procedures for such individuals in an
AFB isolation room or area, (4) masking of individuals with infectious TB or
use of portable containment engineering controls during transport outside of
AFB isolation rooms and return of the individual to an AFB isolation room or
area as soon as is practical after completion of the service or procedure,
and (5) delay of elective high-hazard procedures and elective surgery until
an individual with suspected or confirmed infectious TB is determined to be
noninfectious. It
is important to minimize, to the extent feasible, exposure of employees to
aerosolized M. tuberculosis even while maintaining a high quality of
health care and other required services. Developing policies and procedures
addressing the items listed above will help to assure that this overall goal
is met. For example, there may be times when an individual with suspected or
confirmed infectious TB must leave the isolation room or area (e.g.,
when certain equipment necessary for providing care to the patient cannot be
brought into the room). On these occasions having policies in place that
minimize the time those individuals must be outside the isolation room or
area will help to reduce the likelihood that droplet nuclei are spread. For
example, if a particular procedure must be performed outside of the isolation
room, time could be minimized by taking the individual directly to the
procedure area, performing the procedure upon arrival, and returning the
individual to isolation immediately after completion of the procedure. In
addition, if a procedure is to be performed outside of the isolation room, a
time could be chosen when the procedure area is not being used by others. The
exposure control plan must also contain procedures for minimizing employee
exposure in AFB isolation rooms or areas. For example, policies addressing
minimizing both the number of employees and time that such employees spend in
isolation rooms can reduce exposure. This can be accomplished in a variety of
ways. For example, in order to minimize the number of employees entering an
isolation room, certain tasks or procedures that might normally be done by
several different employees could be done by one person. A nurse coming into
the room to administer daily TB treatment could also bring in the patient's
breakfast at the same time rather than have a hospital dietician deliver the
meal. In addition, the employer must address minimization of time that
employees spend in an isolation room or area. For example, rather than
conducting an entire discharge planning interview with an individual in
person, the employee may be able to collect and convey a large part of the
information over the phone with the individual. Personal contact could be
limited to just the time needed to obtain items requiring direct interaction,
such as the individual's signature. Policies
are to be included that address the masking of individuals with infectious TB
during transport outside of AFB isolation rooms or areas. Masking of
individuals may be accomplished, for example, through the use of surgical
masks or valveless respirators. A barrier such as a surgical mask, when
placed over the mouth of an individual who is coughing, will reduce the
formation of droplet nuclei because the mask will collect and contain the
droplets as they are discharged before they have time to evaporate and form
droplet nuclei. A respirator that does not have an exhalation valve can also
be used to capture droplets being discharged. An exhalation valve would
permit droplets to pass through and discharge into the air, where they could
evaporate and form droplet nuclei. However, while surgical masks prevent the
formation of droplet nuclei, they do not prevent exposure to droplet nuclei. As
the document "Biosafety Precautions for Airborne Pathogens" states: There
is no reciprocity between the means of prevention of the actual formation of
droplet nuclei (coughing into a tissue) and the means of prevention of
exposure (barriers to breathing in the droplet nuclei). Once a droplet
nucleus has been allowed to form, its small size can penetrate the fiber of a
tissue or a surgical mask. Thus these products do not represent adequate
physical barriers to the aerosol transmission of droplet nuclei. The
appropriate barrier is a well fitted respirator that does not allow leakage
of air around the edges and blocks passage of microorganisms in the filter
media (fibers or pores) through which air is inspired. Although a simple
surgical mask applied to a tuberculosis patient who must be transported
outside the isolation room will prevent the dispersal of organisms as droplet
nuclei, such a mask does not provide adequate protection to the individual
who must breathe air containing droplet nuclei. (Ex. 7-134) Since
masking of an individual with suspected or confirmed infectious TB will
reduce the number of droplet nuclei expelled into the air, the employer is
required to develop policies addressing the masking of such individuals
during transport outside of an AFB isolation room. It
is not OSHA's intent to dictate patient management practices, nor will it be
the Compliance Officer's responsibility to determine the correctness of
certain patient management policies. However, the Agency believes that the
employer must consider the above situations and develop policies that address
them, keeping in mind the goal of minimizing employee exposure. This
provision is in accordance with CDC recommendations (Ex. 4B). The
exposure control plan must also contain policies for the delay of elective
transport or relocation within the facility of individuals with suspected or
confirmed infectious TB outside of an AFB isolation room or area. For
example, delaying the transfer of an inmate with suspected or confirmed
infectious TB from one prison to another, where possible, until the inmate
has been determined to be noninfectious, will reduce not only the number of
employees exposed, but will also minimize the exposure of other inmates,
thereby decreasing the risk of transmission of disease. Similarly,
the exposure control plan is to include policies for the delay of elective high-hazard
procedures until an individual with suspected or confirmed infectious TB has
been determined to be noninfectious. Elective high-hazard procedures (e.g.,
pulmonary function testing) or elective surgery (e.g., noncritical
dental procedures) might be easily delayed, without compromising care, until
an individual with infectious TB has been determined to be noninfectious. Paragraph
(c)(2)(iii)(C) requires the employer to list all high-hazard procedures
performed in the workplace. As discussed in paragraph (j), Definitions,
high-hazard procedures are defined as "* * * those procedures performed
on an individual with suspected or confirmed infectious tuberculosis in which
the potential for being exposed to M. tuberculosis is increased due to
the reasonably anticipated generation of aerosolized M. tuberculosis *
* *" Under paragraph (d)(4) of Work Practice and Engineering Controls,
the proposed standard requires that all employers assure that high-hazard
procedures are conducted in an AFB isolation room or area. Thus, listing the
high-hazard procedures will serve to identify those procedures that require
special ventilation considerations (e.g., maintaining negative
pressure and properly exhausting contaminated air). This will assist
employees in determining which procedures must be performed using such
engineering controls and, consequently, will help minimize employee exposure. For
employers who have work settings where TB cases are isolated, paragraph
(c)(2)(iii)(D) requires the employer to develop a schedule for the
inspection, maintenance, and performance monitoring of engineering controls. Engineering
controls required by the proposed standard play an essential role in reducing
employee exposures to M. tuberculosis. Thus, it is necessary that
these controls be appropriately maintained, inspected and monitored in order
to assure that they are functioning properly. Since engineering controls are
mechanical systems, they are prone to occasional lapses in performance caused
by occurrences such as clogged filters, slipping or broken drive belts,
burned-out motors, obstructed ducts, and so forth. Since these situations
cannot be predicted, it is necessary to regularly inspect engineering
controls for proper functioning. Hence, a schedule must be developed for such
activities. In addition, employees who are responsible for the maintenance
will have a record that they can check to see when certain engineering
controls need to be inspected, maintained or monitored. In general, OSHA has
left the time frame for these activities up to the employer, except as
required under paragraphs (d)(5)(ii) and (d)(5)(iii), since the employer is
familiar with the characteristics of the workplace that could affect the
performance of these controls (e.g., dusty conditions, high heat and
humidity, seasonal variations). For
facilities with clinical or research laboratories, Paragraph (c)(2)(iv)
requires that the exposure control plan contain a determination from the
director of the laboratory as to whether the laboratory facility should
operate at Biosafety Level 2 or 3 containment according to CDC/NIH
recommendations. Under paragraph (e), Clinical and Research Laboratories, the
proposed standard requires a number of provisions to eliminate or minimize
exposure in clinical and research laboratory settings. These provisions are
based on CDC/NIH recommendations (Ex. 7-72) for laboratory procedures
performed under Biosafety Levels 2 and 3 for an infectious agent such as M.
tuberculosis. However, as noted in the CDC/NIH recommendations, the selection
of a biosafety level depends on a number of factors and it may be necessary
to adapt the biosafety level based upon such factors. For example, the
CDC/NIH recommendations state that: Occasions
will arise when the laboratory director should select a biosafety level
higher than that recommended. For example, a higher biosafety level may be
indicated by the unique nature of the proposed activity (e.g., the
need for special containment for experimentally generated aerosols for
inhalation studies) or by the proximity of the laboratory to areas of special
concern (e.g., a diagnostic laboratory located near patient care
areas). Similarly, a recommended biosafety level may be adapted to compensate
for the absence of certain recommended safeguards. For example, in those
situations where Biosafety Level 3 is recommended, acceptable safety may be
achieved for routine or repetitive operations (e.g., diagnostic
procedures involving the propagation of an agent for identification, typing
and susceptibility testing) in laboratories where facilities satisfy
Biosafety Level 2 recommendations, provided the recommended Standard
Biological Practices, Special Practices, and Safety Equipment for Biosafety
Level 3 are rigorously followed. (Ex. 7-72, pg. 70) OSHA
agrees that it is appropriate that such decisions be made by the laboratory
director and would allow such adaptations to the CDC/NIH recommendations. However,
regardless of adaptations, OSHA requires the laboratory director to determine
and document the need for controlled access, anterooms, sealed windows,
directional airflow, preventing recirculation of laboratory exhaust air,
filtration of exhaust air before discharge outside, and thimble exhaust
connections for biological safety cabinets. These determinations, along with
any adaptations to the CDC/NIH biosafety level, must be made a part of the
exposure control plan. The documentation will provide information to the
laboratory employees of adaptations to and changes in recommended biosafety
levels. For
employers who provide home health care or home-based hospice care, paragraph
(c)(2)(v) specifies the elements that are to be included in the exposure
control plan. In home health care and home-based hospice care situations,
individuals are in their private homes receiving health care and other
services and thus the employer has limited control over the work site in
which he or she provides those services. In addition, employers providing
such home-based care will not be transferring individuals identified as
having suspected or confirmed infectious TB from their homes to facilities
with isolation capabilities, nor will the employer be initiating isolation
precautions in the home. In recognition of the uniqueness of home-based work
settings, OSHA has limited the elements of the exposure control plan for an
employer who provides home health care and home-based hospice care. The
elements included under this paragraph are intended to address the type of
activities that are likely to occur in the home health care work setting. Under
this paragraph the employer must include procedures for prompt identification
of individuals with suspected or confirmed infectious TB and for minimizing
employee exposure to such individuals. As discussed above, in order for
employees to take proper precautions in protecting themselves from exposure
to TB, it is essential that there be procedures to identity potentially
infectious individuals. In many cases the home health care employer may
already know that the individual has been identified as having suspected or
confirmed infectious TB and has been confined to their home. However, in
other cases, an individual may be suffering from other immunocompromised
conditions and may develop active TB. Because employees in home health care
and home-based hospice care may be providing services to individuals at risk
of developing active TB, it is necessary that there be procedures in place
for identifying those individuals. In addition, the exposure control plan
must include procedures for minimizing employee exposure. Such procedures
might include minimizing the time spent in the home by combining tasks to
limit the number of entries or by minimizing the number of employees who must
enter the home along with the time they spend there. Paragraph (c)(2)(v) also
requires that the exposure control plan include a list of high-hazard
procedures, if any, performed in the workplace and procedures for delaying
elective high-hazard procedures until the individual is noninfectious. Listing
the high-hazard procedures will serve to identify those procedures that may
require special considerations. In the home setting, this would not include
the use of AFB isolation precautions. To the extent possible the employer
should also include procedures for when these types of procedures can be
delayed. This will decrease the exposure of employees to aerosolized M.
tuberculosis that might be generated performing these procedures. Paragraph
(c)(2)(vi) stipulates that the employer must document the number of confirmed
infectious tuberculosis cases encountered in the work setting in the past 12
months in the Exposure Control Plan whenever the employer is using this
information to claim reduced responsibilities related to paragraph (b),
Application, and paragraph (g)(3)(iii)(D), Medical Surveillance, of the
standard. Under paragraph (b), employers are relieved from implementing
certain provisions of the standard if they do not admit or provide medical
services to individuals with suspected or confirmed infectious TB and they
can demonstrate that, in the past 2 years, there have been no cases of
confirmed infectious TB reported in the local county in one or both years
and, if any cases have occurred in one of the past 2 years, fewer than 6
confirmed infectious cases were reported in that year. Furthermore, employers
desiring to follow the limited program must demonstrate that no such cases
have been encountered in his or her employees' work setting in the past 12
months. Under paragraph (g)(3)(iii)(D) of Medical Surveillance, employees
with negative TB skin tests are to be provided with a TB skin test every 6
months if the employee works in an intake area where early identification
procedures are performed in facilities where six or more individuals with
confirmed infectious TB have been encountered in the past 12 months. However,
if the employer can document that fewer than 6 individuals with confirmed
infectious TB have been encountered in the facility, the employee in the
intake area would only have to be provided with a TB skin test annually. The
count of the number of confirmed infectious TB cases in the exposure control
plan would serve to document that fewer than 6 individuals with confirmed
infectious TB had been encountered in the past 12 months, thus relieving the
employer of the burden of providing skin tests every 6 months for those
affected employees. Paragraph
(c)(2)(vii)(A) requires that a copy of the exposure control plan be
accessible to employees. The reason for this is to assure that an employee
can get and consult the exposure control plan within a reasonable time, place
and manner. Having access to the plan encourages employees to develop a
complete understanding of the plan and its application, so that the program
can be carried out by both employer and employees. Having the plan available
also serves as an on-site adjunct to the overall infection control program
and may reinforce the training programs. For
fixed work sites and primary workplace facilities, the plan must be
maintained on-site at all times. For those situations where an employee(s)
travels between work sites or where the employee's work is carried out at
more than one geographical location, the plan may be maintained at the
primary workplace facility. To ensure access, the plan should be in a central
location where an employee may see it whenever he or she wishes. However, in
order to allow flexibility, OSHA is not specifying where the plan must be
kept. The employer is permitted to determine where the plan is kept provided
that the employee can access a copy of the plan at the workplace, within the
workshift. For example, if the plan is maintained on a computer, access to
the computer or hard copy must be available to the employee. Likewise, if the
plan is comprised of several separate policy documents, copies of all
documents must be accessible in addition to any general policy statement or
guiding document that may exist. Paragraph
(c)(2)(vii)(B) requires that the exposure control plan be reviewed at least
annually and updated whenever necessary to reflect new or modified tasks,
procedures, or engineering controls that affect occupational exposure and to
include new or revised employee positions with occupational exposure. An
example of such a situation would be when an employer in a facility that had
previously transferred individuals with suspected or confirmed infectious TB
decided that such individuals would be admitted and provided medical
services. The purpose of this requirement is to assure that all new tasks and
procedures are evaluated in order to determine whether they could result in
occupational exposure. New and revised job classifications must be added to
the lists of job classifications and tasks and procedures identified in
(c)(1)(i) of this section in order to assure full coverage of occupationally
exposed employees. The updating must occur as soon as feasible and may not be
postponed until the annual review. Paragraph
(c)(2)(vii)(C) requires that the exposure control plan be made available to
the Assistant Secretary and the Director upon request for examination and
copying. The purpose of this requirement is to allow the OSHA representative
to review an employer's plan, including the exposure determination of
employees at risk for occupational exposure. Although the Assistant Secretary
or the Director could request the plan at any time, it will usually be
requested by an OSHA compliance safety and health officer (CSHO) during the
course of a workplace inspection. The CSHO needs to examine the plan in order
to see what procedures and program planning for the control of occupational
exposures have been instituted and whether they meet the requirements of the
standard. Paragraph (d) Work Practices and Engineering Controls It
is generally acknowledged that protection of the employee is most effectively
attained by elimination or minimization of the hazard at its source, which
engineering controls and work practices are both designed to do. Industrial
hygiene principles also teach that control methods that depend upon the
vagaries of human behavior are inherently less reliable than well-maintained
mechanical methods. For these reasons, OSHA has preferred engineering and
work practice controls and has required, under paragraph (d)(1), that they be
used to eliminate or minimize employee exposure to M. tuberculosis. Nevertheless,
OSHA recognizes that situations may exist in which neither of these control
methods is feasible and that, in these circumstances, employee protection
must be achieved through the use of personal protective equipment, primarily
respirators. In other situations, personal protective equipment may have to
be utilized in conjunction with engineering controls and/or work practices to
obtain a further reduction in employee exposure. Engineering
controls serve to reduce employee exposure in the workplace by either
removing the hazard or isolating the worker from exposure. These controls
include process or equipment redesign, process or equipment enclosure (e.g.,
biosafety cabinets), and employee isolation. In general, engineering controls
act on the source of the hazard and eliminate or reduce employee exposure
without reliance on the employee to take self-protective action. In
comparison, work practice controls reduce the likelihood of exposure through
alteration of the manner in which a task is performed (e.g., closing
the door of an AFB isolation room immediately upon entering or exiting). Although
work practice controls also act on the source of the hazard, the protection
they provide is based upon employer and employee behavior rather than installation
of a physical device. In many instances these two control methodologies work
in tandem, because it is often necessary to employ work practice controls to
assure effective operation of engineering controls. Under the provisions of
the preceding paragraph, Exposure Control Plan, the employer is required to
develop a number of work practices relative to controlling occupational
exposure to TB. In paragraph (d)(2), these work practices are required to be
implemented in the work setting. In
developing the methods of compliance section for this proposal, OSHA
carefully considered the work environments that have the potential for
producing occupational exposures. Since the source of the hazard is
frequently a living person, typical methods of reducing or eliminating the
hazard at the source may not always be feasible. For example, in an
industrial operation a process may be entirely enclosed and operated or
monitored by an employee at a remote location, a situation that would rarely,
if ever, occur in the work settings covered by this standard. The Agency
believes, therefore, that prevention of exposures to M. tuberculosis
will often require use of a combination of control methods to achieve
adequate protection of employees. Paragraph (d)(1) requires work practices
and engineering controls to be used to eliminate or minimize employee
exposures. Not
all facilities will have the capabilities to admit or provide medical
services to individuals with suspected or confirmed infectious tuberculosis. Consequently,
these facilities will have to transfer such individuals to another facility
where isolation rooms or areas are available. Paragraph (d)(3) requires that
individuals with suspected or confirmed infectious TB must be identified and,
except in settings where home health care or home-based hospice care is
provided, shall be: (i) masked or segregated in such a manner that contact
with employees who are not wearing respiratory protection is eliminated or
minimized until transfer or placement in an AFB isolation room or area can be
accomplished; and (ii) placed in an AFB isolation room or area or transferred
to a facility with AFB isolation rooms or areas within 5 hours from the time
of identification, or temporarily placed in AFB isolation within 5 hours
until placement or transfer can be accomplished. Masking
or segregation of individuals with suspected or confirmed infectious TB while
those individuals are awaiting placement in isolation or transfer to another
facility is done to assure that employee exposure is minimized to the extent
feasible. This provision, drawn from CDC recommendations (Ex. 4B), is aimed
at minimizing the exposure of employees in areas where individuals are first
identified as having suspected or confirmed infectious TB. Although CDC
recommends masking such individuals, OSHA presents a choice of masking or
segregation because the Agency believes that this practice is directly
involved with the medical management of such individuals. It is OSHA's
mission to protect employees from occupational exposure to tuberculosis and
it is not the Agency's intent to dictate medical practice relative to
individuals with suspected or confirmed infectious TB. Therefore, where the
employer has chosen not to mask individuals with suspected or confirmed
infectious TB when they are not in isolation rooms or areas or when such
individuals cannot be masked (e.g., because they are combative), the
employer must segregate these individuals in a manner such that contact with
employees who are not wearing respiratory protection is eliminated or
minimized. Segregation could be accomplished, for example, by having the
individual wait in an area out of the main traffic of a waiting room or
intake area or in a vacant examination room that is not needed for
patient/client consultations. The time that a facility can permit an
individual to await placement or transfer is limited to 5 hours. After that
the individual must be placed in isolation. The
primary purposes of AFB isolation rooms or areas are to (1) isolate patients
who are likely to have infectious TB from unprotected employees, (2) prevent
escape of droplet nuclei from the room, thus preventing entry of M.
tuberculosis into the corridor and other areas of the facility where
unprotected employees may be exposed, and (3) provide an environment that
will promote reduction of the concentration of droplet nuclei through various
engineering controls (Ex. 4B). All of these will reduce employee exposure. Indeed,
placement of individuals with suspected or confirmed infectious TB in an AFB
isolation room is the most effective way to prevent or lessen transmission. OSHA
has proposed that individuals with suspected or confirmed infectious TB be
isolated or transferred within 5 hours from the time of being identified as a
suspected or confirmed case. The Agency realizes that the time it will take
to isolate or transfer an individual once he or she is identified as having
suspected or confirmed infectious TB may vary and that circumstances may
arise that cause delays in initiating isolation (e.g., all isolation
rooms may be occupied by other patients). However, OSHA is also concerned
about the amount of time an individual, who has been identified as having
suspected or confirmed infectious TB, should be permitted to stay in
non-isolation areas. Individuals who must wait for extended periods of time
before placement in AFB isolation or transfer may present a risk of exposure
to employees working in these areas even though these individuals may be
masked. A study by Moran et. al. shows that emergency departments that made a
presumptive diagnosis of TB were able to initiate isolation in an average of
5 hours from the time of patient registration (Ex. 7-251). Patient
registration usually precedes identification. The standard requires that
procedures be in place for prompt identification of individuals with
suspected or confirmed infectious TB. In view of this requirement and the
fact that the study was based on time elapsed from patient registration to
isolation, which included the time the patient waited to be medically
observed, the Agency has preliminarily concluded that five hours from the
time of being identified is a reasonable cutoff point for transfer or
placement in isolation. The
Agency's concern regarding permitting identified individuals to wait for
extended periods, even though they are masked, before they are transferred or
isolated is not unfounded. The American Thoracic Society, in its document
Control Of Tuberculosis In The United States, states: *
* *Patients unable to cooperate in covering coughs and sneezes can wear
ordinary surgical masks for short periods, for example, while being
transported within institutions. For longer periods, masks on patients are
stigmatizing, uncomfortable, and probably ineffective. (Ex. 5-80) (emphasis
added) Consequently,
a cutoff point of 5 hours has been proposed as the maximum amount of time
individuals who have been identified with suspected or confirmed infectious
TB may await transfer or placement into AFB isolation. As discussed under the
Exposure Control Plan, paragraph (c), employers are required to have
procedures in place for isolating or transferring individuals identified with
suspected or confirmed infectious TB so that AFB isolation can be executed
expeditiously. Five hours would appear to be a reasonable amount of time to
carry out these procedures. OSHA believes that longer periods of time are
likely to pose too great a risk of exposure to employees in the vicinity. The
longer an individual with suspected or confirmed infectious TB remains
outside of AFB isolation, the greater the risk of transmission. It
should be noted that the 5-hour cutoff is the amount of time allotted per
facility to accomplish AFB isolation or transfer of these individuals. More
specifically, if an individual spent 4 hours awaiting transfer at an
identifying facility, the receiving facility would still be allowed 5 hours
to accomplish isolation, not just the one hour remaining since initial
identification of the individual. The intent of the proposed facility-based
5-hour period is to allow the receiving facility adequate time to accomplish
isolation and to recognize that the receiving facility should not be held
responsible for circumstances beyond the facility's control (e.g., the
time the individual waited before arrival at the receiving facility). If
placement or transfer cannot be completed within five hours, it must be done
as soon as possible thereafter. In addition, the employer must assure in such
a case that his or her facility has AFB isolation rooms or areas for the
isolation of the individual until placement or transfer can be accomplished. More
specifically, it is not necessary to construct a dedicated AFB isolation room
or area to isolate such individuals while awaiting transfer or placement
within the facility. The definition of "AFB isolation room or area"
states that this may be a room, area, booth, tent, or other enclosure that is
maintained at negative pressure to adjacent areas in order to control the
spread of aerosolized M. tuberculosis. For example, such isolation
might be achieved by placing a portable stand-alone HEPA filtration unit
(vented to the outside) in an unused examination room. Another method is the
use of a rigid enclosure on casters with a ventilation unit to achieve
negative pressure, a window kit to safely exhaust the enclosure's air to the
outside, and a digital pressure monitor to assure maintenance of negative
pressure within the enclosure. As is the case with any AFB isolation room or
area, the means used to isolate an individual awaiting placement or transfer
must achieve negative pressure and have its air safely discharged to the
outside. OSHA seeks comment regarding the 5-hour limit on placement or
transfer and measures that can be used for AFB isolation in those situations
when transfer or placement cannot be accomplished within that time. Paragraph
(d)(4) stipulates that high-hazard procedures must be conducted in AFB
isolation rooms or areas. High-hazard procedures as defined in paragraph (b),
Definitions, are procedures performed on an individual with suspected or
confirmed infectious TB in which the probability of M. tuberculosis
being expelled into the air is increased. These procedures include, but are
not limited to, endotracheal intubation and suctioning, diagnostic sputum
induction, aerosol treatments (including pentamidine therapy), pulmonary
function testing, and bronchoscopy. These procedures also include autopsy,
clinical, surgical, and laboratory procedures that may aerosolize M.
tuberculosis. In view of the increased probability of droplet nuclei
generation associated with these procedures, all high-hazard procedures are
required to be performed in rooms, areas, or booths that meet AFB isolation
criteria (e.g., negative pressure) in order to contain the droplet nuclei
and eliminate or minimize employee exposure. Other procedures that may
generate aerosols (e.g., irrigation of tuberculous abscesses,
homogenizing or lyophilizing infectious tissue), are also covered by this
provision. (See paragraph (e) of this proposal for requirements for
microbiological practices and containment equipment in laboratories.) Paragraph
(d)(5) requires that engineering controls be used in facilities that admit or
provide medical services or AFB isolation to individuals with suspected or
confirmed infectious TB except in settings where home health care or
home-based hospice care is being provided. For example, engineering controls
must be used in isolation rooms or areas, areas where high hazard procedures
are performed, and autopsy rooms where M. tuberculosis may be
aerosolized. This provision specifically excepts settings where home health
care or home-based hospice care is being provided. In such situations, the
employer is not in control of the employee's work setting because the setting
is the private home of the individual being provided with care. In view of
this, an employer providing home health care or home-based hospice care would
not be required to implement engineering controls in the individual's home. In
conjunction with this provision, paragraph (d)(5)(i) requires that negative
pressure be maintained in AFB isolation rooms or areas. The purpose of this
provision is to prevent the escape of aerosolized M. tuberculosis from
a room and into the corridors and other areas of the facility where
unprotected employees may be exposed. In order for air to flow from one area
to another, there must be a difference in the pressure between the two areas.
Air will flow from the higher pressure to the lower pressure area. The lower
pressure area is at "negative pressure" relative to the higher
pressure area. The level of negative pressure achieved will depend on the
physical configuration of the area, including the air flow path and flow
openings. A pressure differential of 0.001 inch of water and an inward air
velocity of 100 feet per minute (fpm) are minimum acceptable levels. The
pressure difference necessary to achieve and maintain negative pressure in a
room is very small and may be difficult to measure accurately. Negative
pressure can be achieved by balancing the room supply and exhaust flows to
set the exhaust flow to a value of 10 % [but no less than 50 cubic feet per
minute (cfm)] greater than the supply (Ex. 4B). As
stated above, the negative pressure principle plays an important role in
controlling the spread of M. tuberculosis to other areas of the
facility where unprotected workers may be exposed. In isolation rooms and
areas, and in areas where high hazard procedures (including autopsies) are
performed, engineering controls creating negative pressure will prevent the
escape of droplet nuclei from the room, thus preventing dispersion of M.
tuberculosis into the corridor and other areas of the facility where
unprotected employees may be working. In
addition, negative pressure fulfills the secondary purpose of general
ventilation by reducing the concentration of contaminants in the air. General
ventilation maintains air quality by two processes, dilution and removal of
airborne contaminants. Dilution reduces the concentration of contaminants in
a room by supplying air that does not contain those contaminants. The supply
air mixes with and then displaces some of the contaminated room air, which is
subsequently removed from the room by the exhaust system. This process
reduces the concentration of droplet nuclei in the room air and the risk of
TB transmission. OSHA
is not proposing to allow the use of ultraviolet germicidal irradiation
(UVGI) in place of ventilation for controlling aerosolized M. tuberculosis.
Although the germicidal properties of certain wavelengths of ultraviolet
light (UV-C) are generally recognized, the Agency has not included UVGI as a
primary engineering control in the proposed standard. With regard to the use
of UVGI, CDC states: Because
the clinical effectiveness of UV systems varies, and because of the risk for
transmission of M. tuberculosis if a system malfunctions or is
maintained improperly, UVGI is not recommended for the following specific
applications: 1. Duct systems using UVGI are not recommended as a substitute
for HEPA filters if air from isolation rooms must be recirculated to other
areas of a facility. 2. UVGI alone is not recommended as a substitute for
HEPA filtration or local exhaust of air to the outside from booths, tents, or
hoods used for cough-inducing procedures. 3. UVGI is not a substitute for
negative pressure. (Ex. 4B) The
CDC goes on to discuss a number of factors that affect the effectiveness of
UVGI and UV lamps in killing airborne tubercle bacilli. These factors include
the intensity of UVGI, the duration of irradiation of the organism, the
relative humidity of the environment, the age of the UV lamp, and the amount
of dust on the lamp's surface (Ex. 4B). In light of this information, the
Agency does not believe that UVGI can reliably and uniformly control airborne
tubercle bacilli. Consequently, UVGI is not acceptable as a primary
engineering control. However, some employers may choose to use UVGI as a
supplement to ventilation or HEPA filtration. In recognition of this, OSHA
has included information regarding UVGI safety and health concerns in
Appendix D of this section. Paragraph
(d)(5)(ii) requires that in those areas where negative pressure is required
(i.e., AFB isolation rooms or areas), maintenance of negative pressure must
be qualitatively demonstrated (e.g., by smoke trails) daily while in
use for tuberculosis isolation. In Supplement 3 of its 1994 guidelines, CDC
states: TB
isolation rooms should be checked daily for negative pressure while being
used for TB isolation. (Ex. 4B) The
principle and advantages of negative pressure have been discussed above. Proper
maintenance of negative pressure will prevent the contaminated air from
escaping from the room or area and exposing unprotected employees. One means
of qualitatively demonstrating negative pressure is through the use of smoke
trail testing (see Appendix G of this section). Other methods include flutter
strips or continuous monitoring devices. With regard to the safety and
effectiveness of these methods, the CDC states: The
concern over the use of smoke tubes is unfounded. Controlled tests by NIOSH
have shown that the quantity of smoke that is released is so minute that it
is not measurable in the air. The location of the patient and the length of
time the patient is exposed dilute the smoke to several orders of magnitude
below an 8-hour exposure limit. It is not practical and often not effective
to use flutter strips or continuous monitoring devices as alternatives to
indicate directional air movement. The air flow (due usually to the small
clearance area under the door) is insufficient to move the flutter strip. Likewise,
low negative pressure, which will satisfactorily provide adequate directional
air flow into the isolation room, may not be readable on continuous
monitoring devices. Devices must be capable of reading 0.001 inch of water,
the established minimum, to be effective. (Ex. 4B) In
light of this information, employers should be aware that when choosing a
method other than smoke trails to demonstrate maintenance of negative
pressure, the method chosen should be reviewed carefully in order to assure
that the intended test can be effectively conducted. Paragraph
(d)(5)(iii) stipulates that engineering controls must be maintained, and
inspected and performance monitored for filter loading and leakage every six
months, whenever filters are changed, and more often if necessary to maintain
effectiveness. The primary intent of this provision is to assure that
engineering controls are maintained in such a manner that they continue to
function effectively. As discussed previously, a number of factors can affect
the functioning of engineering controls, such as frozen bearings, broken
belts, and burned out motors. It is the employer's responsibility to maintain
engineering controls in proper working condition. That is, if a belt breaks
on a fan motor, it is not appropriate to delay repairs until the six-month
inspection. This provision does, however, stipulate a maximum time period of
six months between inspections and performance monitoring of engineering
controls and HEPA filters in air systems carrying air that may reasonably be
anticipated to contain aerosolized M. tuberculosis. The employer's
maintenance schedule may specify more frequent inspection, maintenance, and
performance monitoring based upon conditions found in that particular work
site. For example, the employer, being more familiar with his or her own work
setting, may have knowledge that the work environment is very dusty, thus
necessitating a more frequent period for changing the filters. When filters
are changed, performance monitoring must be conducted to assure that the
filter has been correctly installed and is functioning properly. In view of
the importance of these systems in reducing the concentration of droplet nuclei
and thereby the risk of TB transmission, OSHA believes that six months is the
longest period that these systems should be allowed to operate without
inspection and performance monitoring. This maximum six-month period of time
between consecutive inspections and performance monitoring of HEPA filters is
supported by CDC (Ex. 4B). Paragraph
(d)(5)(iv) requires that air from AFB isolation rooms or areas must be
exhausted directly outside, away from intake vents and employees. If the air
from these areas cannot be exhausted in such a manner or must be
recirculated, it must pass through HEPA filters before discharge or
recirculation. In
order for the air to be safely discharged, exhaust ducts must not be located
near areas that may be populated (e.g., sidewalks or windows that may
be opened). In addition, ventilation system exhaust discharges must be
designed to prevent re-entry of exhaust air. Wind blowing over a building
creates a highly turbulent recirculation zone, which can cause re-entry of
the exhaust into the building. Exhaust flow needs to be discharged above the
zone. When exhaust air cannot be safely discharged, it must pass through HEPA
filters to remove droplet nuclei, thereby precluding re-entry of potentially
contaminated air or exposure of individuals who may have to pass through the
exhaust airstream. The employer should be aware that exhausting of this air
may also fall under federal, state and local regulations concerning
environmental discharges. This
provision also states that if a portion of this air is recirculated, it must
pass through a properly designed, installed, and maintained HEPA filter
before discharge back into general facility ventilation. HEPA filters clean
air through the physical removal of particulates from the airstream. These
filters have a minimum removal efficiency of 99.97 % for particles >0.3
microns in diameter. Droplet nuclei of M. tuberculosis range in size
from 1 micron to 5 microns in diameter. Therefore, HEPA filtration can be
expected to remove most droplet nuclei from the air. It should be noted that
whenever feasible, exhaust air from the AFB isolation rooms or areas must be
exhausted to the outside. In its 1994 guidelines, CDC states: Air
from TB isolation rooms and treatment rooms used to treat patients who have
confirmed or suspected infectious TB should be exhausted to the outside in
accordance with applicable Federal, state, and local regulations. The air
should not be recirculated into the general ventilation. In some instances,
recirculation of air into the general ventilation system from such rooms is
unavoidable (i.e., in existing facilities in which the ventilation system or
facility configuration makes venting the exhaust to the outside impossible). In
such cases, HEPA filters should be installed on the exhaust duct leading from
the room to the general ventilation system to remove infectious organisms and
particulates the size of droplet nuclei from the air before it is returned to
the general ventilation system (Section II.F; Suppl. 3). Air from TB isolation
rooms and treatment rooms in new or renovated facilities should not be
recirculated into the general ventilation system. (Ex. 4B) The
Agency agrees with CDC that exhaust air should be vented to the outside. However,
OSHA recognizes that there may be instances where outside discharge may not
be feasible and has, therefore, permitted recirculation with HEPA filtration
of the recirculated air, in such instances. Paragraph
(d)(5)(v) states that ducts carrying air that may reasonably be anticipated
to contain aerosolized M. tuberculosis must be maintained under
negative pressure for their entire length before in-duct HEPA filtration or
until the ducts exit the building for discharge. Ducts maintained under
negative pressure will contain exhaust air within the system. Air will not
escape to the outside as it would under positive pressure even if there are
leaks in the ducts. The purpose of this provision is to prevent escape of air
that may contain aerosolized M. tuberculosis into areas where
occupational exposure is not anticipated and unprotected employees may be
exposed. Paragraph
(d)(5)(vi) requires that, while in use for TB isolation, doors and windows of
AFB isolation rooms or areas must be kept closed except when doors are opened
for the purpose of entering or exiting and when windows are part of the
ventilation system being used to achieve negative pressure. For example, the
window may be serving as the exit for the exhaust from an in-room HEPA
filtration unit. As stated above, AFB isolation rooms and areas are to be
maintained under negative pressure while in use for TB isolation. Negative
pressure in a room can be altered by small changes in the ventilation system
operation, or by the opening and closing of the isolation room doors or
windows. In order to assure that the ventilation system functions as
intended, it is essential that, once an operating configuration has been
established, doors and windows be opened only when necessary. Paragraph
(d)(5)(vii) stipulates that when an AFB isolation room or area is vacated by
an individual with suspected or confirmed infectious TB, the room or area
must be ventilated for an appropriate period of time, according to current
CDC recommendations for a removal efficiency of 99.9 %, before permitting
employees to enter without respiratory protection (see Appendix C of this
section). The time required for removing airborne particles from an enclosed
space depends on several factors. These include the number of air changes per
hour (which is determined, in part, by the number of cubic feet of air in the
room or booth), the rate at which air is entering the room or booth at the
intake source versus the rate at which it is being exhausted, the location of
the ventilation inlet and outlet, and the physical configuration of the room
or booth. The times needed to achieve a given removal efficiency (i.e., 90 %,
99 %, and 99.9 %) presented in Appendix C of this section assume perfect air
mixing within a space. However, perfect mixing of air normally does not occur
because a number of factors, such as room configuration, may influence the
movement of air. Because perfect air mixing is not likely to occur, the
necessary time required for a specific removal efficiency, as presented in
Appendix C of this section, may be underestimated. In order to compensate for
this shortcoming, OSHA has proposed that the most conservative (i.e.,
protective) removal efficiency, i.e., 99.9 %, be used to determine the
appropriate amount of time an AFB isolation room or area must be ventilated
before permitting employees to enter without respiratory protection. Using
this conservative approach will help to assure that an appropriate time has
passed before unprotected employees enter the area, even in situations where
perfect air mixing has not occurred. Ventilation of the room would not be
necessary if the room was previously occupied by an individual with suspected
infectious tuberculosis and that individual was medically determined to be
noninfectious, since there would be no droplet nuclei present. Paragraph
(d)(6) requires that the employer must inform any outside contractor who
provides temporary or contract employees who may incur occupational exposure
of the hazard, so that the contractor can institute precautions to protect
his or her employees. OSHA is concerned that the contractor be aware of the
existence of TB hazards so that appropriate actions can be undertaken to
prevent the contractor's employees from being unwittingly exposed. By
conveying such information to the contractor, accountability for these
employees is established. If the contractor is aware of the hazards, then it
is the responsibility of the contractor to institute procedures to protect
his or her employees from occupational exposure to M. tuberculosis. Paragraph (e) Clinical and Research Laboratories This
paragraph addresses requirements that must be met by clinical and research
laboratories engaged in the culture, production, concentration,
experimentation, and manipulation of M. tuberculosis. These
requirements apply in addition to the other requirements of the standard. The
risks associated with direct and routine work with pathogens have long been
recognized: Microbiology
laboratories are special, often unique, work environments that may pose
special infectious disease risks to persons in or near them. Personnel have
contracted infections in the laboratory throughout the history of
microbiology. (Ex. 7-72) Clinical
and research laboratories working with M. tuberculosis are no
exception, and the risks associated with work in such facilities warrant
additional protective measures. Prior
to 1984, no single code of practice, standards, guidelines or other
publication providing detailed descriptions of techniques or equipment for
laboratory activities involving pathogens was available. In that year, the
CDC and the National Institutes of Health (NIH) published guidelines entitled
"Biosafety in Microbiological and Biomedical Laboratories". These
biosafety guidelines were based on combinations of standard and special
practices, equipment, and facilities recommended for use when working with
various infectious agents in laboratory settings. The most current revision
of these guidelines is dated 1993. (Ex. 7-72) The
biosafety guidelines are not limited to M. tuberculosis, which is the
subject of this standard. They are applicable to work with any infectious
agent. The basic format for the biosafety guidelines categorizes infectious
agents and laboratory activities into four classes or levels denoted as
Biosafety Levels 1 through 4. These biosafety levels (BSL) are comprised of
combinations of laboratory practices and techniques, safety equipment, and
laboratory facilities appropriate for the operations performed and the hazard
posed. The Guidelines indicate the BSL to be used when working with various
infectious agents and infected animals. There
is a risk to employees working with materials containing M. tuberculosis.
When the concentration of this bacterium is increased as the result of
growing it in cell culture or through artificial concentration, then the risk
of transmission to employees increases if the bacteria are not contained. Therefore,
the proposed standard requires the employer to implement a number of
provisions specifically related to these laboratory work settings. The
requirements in paragraph (e), including those regarding biosafety cabinets,
are derived primarily from the CDC/NIH recommendations found in
"Biosafety in Microbiological and Biomedical Laboratories" (Ex.
7-72). Only those provisions that relate to the health and safety of
employees are required by the standard. The provisions in paragraph (e) are a
minimal program, and OSHA anticipates that employers affected by this
paragraph will continue to follow any other appropriate portions of the above
recommendations in addition to the requirements of this standard. In
addition, the employer is responsible for following this entire standard (e.g.
training employees, medical surveillance). Paragraph
(e) applies to two types of facilities that OSHA has designated as
"clinical laboratories" and "research laboratories." For
the purpose of this standard a clinical laboratory is a laboratory or area of
a facility that conducts routine and repetitive operations for the diagnosis
of TB, such as preparing acid-fast smears and culturing sputa or other
clinical specimens for identification, typing or susceptibility testing. A
research laboratory is a laboratory that propagates and manipulates cultures
of M. tuberculosis in large volumes or high concentrations that exceed
those used for the identification and typing activities common to clinical
laboratories. The
proposed standard requires, in paragraphs (e)(2)(i)(A) through (D), that both
clinical and research laboratories follow several standard microbiological
practices. All procedures are to be performed in a manner that minimizes the
creation of aerosols. In view of the mode of transmission of M.
tuberculosis, that is, through inhalation of airborne organisms, this
provision is extremely important in eliminating or minimizing employee
exposure. It is the responsibility of the employer to evaluate laboratory
tasks and institute the measures necessary to minimize the creation of
aerosols. OSHA
also proposes to adopt the good laboratory and infection control practice of
prohibiting pipetting or suctioning by mouth. The use of cotton plugs or
other barriers does little to reduce the hazards of mouth pipetting. Even a
technician who is skilled in mouth pipetting may inadvertently suck fluids
containing M. tuberculosis into the mouth. In addition to producing M.
tuberculosis-containing aerosols when the fluid is expelled, these fluids
may also contain bloodborne pathogens that would have contacted the
employee's mucous membranes (i.e., the mouth) as well as any blisters, cuts,
or other lesions in the mouth or on the lips. Work
surfaces and laboratory equipment must be decontaminated at the end of each
shift and after any spill of viable material. This is recognized as good
laboratory practice in minimizing the spread of contamination. Finally,
the proposed standard requires that all cultures, stocks, and other wastes
contaminated with M. tuberculosis be decontaminated before disposal by
a decontamination method, such as autoclaving, known to effectively destroy M.
tuberculosis. Materials to be decontaminated outside of the immediate
laboratory are to be placed in a durable leakproof container, closed to
prevent leakage for transport from the laboratory, and labeled or color coded
in accordance with paragraph (h)(1)(ii) of this section. Decontamination
before disposal helps assure that other employees are not inadvertently
exposed to the bacterium. Although
the proposed standard requires proper containerization of laboratory wastes,
it includes no such requirement for wastes originating from the provision of
care or services to individuals with suspected or confirmed infectious TB (e.g.,
facial tissues that the individual has used). The reason for this is that
items, such as facial tissues, capture and contain the liquids generated by
the individual. Once captured, the liquid is not readily aerosolized. In
their guidelines, the CDC states: Disposable
items contaminated with respiratory secretions are not associated with
transmission of M. tuberculosis. (Ex. 4B) In
the laboratory, however, the liquids containing M. tuberculosis are
generally not captured or contained on an item but exist as an individual
specimen or culture. Also, in some instances, the bacilli have been
concentrated. The possibility, therefore, for formation of droplet nuclei
from these wastes is increased. Consequently, it is necessary to properly
containerize and label laboratory wastes to assist in preventing droplet
nuclei formation and possible infection. Proper containerization and labeling
of wastes to be decontaminated outside a laboratory not only help prevent
employee exposure but also warn employees who come in contact with this waste
of the hazard within the container. Paragraphs
(e)(2)(ii)(A) through (E) describe special practices to be followed in
clinical and research laboratories, such as limiting access to the laboratory
to authorized personnel, preparing and maintaining a biosafety manual,
properly containerizing materials contaminated with M. tuberculosis,
immediately containerizing and cleaning up all spills potentially
contaminated with M. tuberculosis, and posting a sign with the
universal biohazard symbol on access doors when materials containing or
animals infected with M. tuberculosis are present. Limiting access to
these laboratories assures that unauthorized individuals are not placed at
risk, and that they do not distract or otherwise interfere with the activity
of the authorized employees. This provision works in concert with the
requirement for signs in paragraph (h)(2)(iv) and ensures that only employees
who meet the special requirements set forth by the laboratory director, which
will include training, personal protective equipment, and other requirements,
could enter the area. The
requirement for a biosafety manual helps assure that any additional procedures
are developed to address situations that are unique to a particular facility
and to provide appropriate protection to exposed employees. The manual must
be reviewed as necessary and at least annually. The manual must also be
updated as necessary to reflect changes in the work setting. The phrase
"as necessary" has been used to indicate that updating of the
manual to reflect work setting changes is to be done as soon as possible and
is not to be postponed until the annual review. Employees are required to read
the biosafety manual's sections on potential hazards and practices and
procedures. The
requirement that contaminated material removed from the work area be placed
in a container that prevents leakage during collection, handling, processing,
storage, transport, or shipping is to assure that there are no accidental
spills or other contamination that may place other employees at risk. Paragraph
(e)(2)(ii)(D) requires that spills be cleaned up immediately by employees
trained and equipped to work with potentially concentrated M. tuberculosis.
Because M. tuberculosis can become aerosolized during cleanup
procedures, the task cannot be done by someone who is not skilled and
properly equipped. In addition, exposure incidents must be reported so that
the post-exposure management and follow-up required by paragraph (g) can be
initiated and the circumstances surrounding the exposure incidents can be
investigated. Paragraph
(e)(2)(ii)(E) requires that, when materials or animals infected with M.
tuberculosis are present in the laboratory, a hazard warning sign, in
accordance with paragraph (h)(2)(iv) of Communication of Hazards and
Training, incorporating the universal biohazard symbol, shall be posted on
all laboratory and animal room access doors. Because M. tuberculosis
is present in the materials listed above, it is necessary to warn individuals
who may enter this area of the hazards that are present so that they can take
proper precautions to guard themselves against exposure. The
requirements of paragraph (e)(2)(iii)(A) stipulate that whenever activities
with the potential for generating aerosols of M. tuberculosis are
conducted, and whenever high concentrations or volumes of M. tuberculosis
are used, a certified Class 2 biological safety cabinet must be used. Such
materials may be centrifuged in the open laboratory, i.e., outside of a
biosafety cabinet, if sealed rotor heads or centrifuge safety cups are used. These
requirements protect employees from exposure during the performance of
procedures by assuring that aerosolized M. tuberculosis will be
contained and kept away from the worker's breathing zone. Paragraph
(e)(2)(iii)(B) requires that biological safety cabinets shall be certified
when they are installed, annually thereafter, whenever they are moved, and whenever
filters are changed. Biological safety cabinets must be certified to ensure
that they will provide the proper protection. The National Sanitation
Foundation (NSF) Standard 49 describes design, construction, and performance
criteria for biosafety cabinets. (Ex. 7-135) Moreover, this NSF standard is
subject to periodic review by the NSF in order to keep the requirements
consistent with new technology. OSHA has incorporated the current NSF
Standard 49 performance criteria into the OSHA standard. For example,
Standard 49 states: *
* * that each cabinet be tested and performance evaluated on site, assuring
that all physical containment criteria are met at the time of installation,
prior to use, and periodically thereafter. (Ex. 7-135) NSF
Standard 49 also calls for recertification of cabinets at least annually,
when HEPA filters are changed, and after maintenance repairs or relocation of
a cabinet. Therefore, OSHA believes that the requirements in the proposed
standard are appropriate and that cabinets that are certified by the
manufacturer as Class 2 or 3 will provide adequate protection to employees. Paragraph
(e)(2)(iv) requires that a method for decontamination of wastes contaminated
with M. tuberculosis (e.g., autoclave, chemical disinfection,
incinerator, or other approved decontamination system known to effectively
destroy M. tuberculosis) must be available within or as near as
feasible to the work area. The availability of such methods of
decontamination is required for inactivating or destroying M. tuberculosis
in or on a variety of media, including culture fluids, plastic ware, and
equipment. These materials must be decontaminated to prevent potential
aerosolization of M. tuberculosis and inadvertent exposure of
employees outside of the laboratory. Research
laboratories working with M. tuberculosis are held to several
additional requirements. Paragraph (e)(3)(i)(A) requires that research
facilities keep laboratory doors closed when working with M. tuberculosis.
Paragraph (e)(3)(i)(B) requires that access to the work area be limited to
persons who comply with specified entry and exit requirements. These
provisions are adopted from the CDC/NIH recommendations for "Biosafety
in Microbiological and Biomedical Laboratories" (Ex. 7-72). In addition,
paragraph (e)(3)(i)(C) requires that respiratory protection shall be worn in
research laboratories when aerosols cannot be safely contained (e.g.,
when aerosols are generated outside a biological safety cabinet). As stated
previously, research laboratories are working with larger volumes and higher
concentrations of M. tuberculosis than clinical laboratories. As such,
the risk to employees from aerosolized bacilli is increased, necessitating
that these employees be protected whenever lapses in containment occur. An
example of when aerosols would be generated would be when a flask containing M.
tuberculosis is dropped and broken outside of the biosafety cabinet. Another
example would be centrifugation of M. tuberculosis-containing cultures
in an open centrifuge without aerosol-proof centrifuge safety containers, or
utilizing such containers but then opening them outside of the biosafety
cabinet (Ex. 7-134). Paragraph
(e)(3)(ii) requires employers to ensure that employees manipulating cultures
and clinical or environmental materials that may generate M. tuberculosis-containing
aerosols, challenging animals with M. tuberculosis aerosols,
harvesting tissues or fluids from infected animals, or performing necropsies
on infected animals use the appropriate containment equipment and/or devices
when performing these activities. Such equipment and devices include Class 2
or 3 biosafety cabinets, or appropriate combinations of personal protective
equipment and physical containment devices (such as respirators, centrifuge
safety cups, sealed centrifuge rotors, and containment caging for animals). This
requirement, like the others in this paragraph, is intended to ensure that
employees are protected during the performance of these potentially
high-hazard procedures. Research
laboratories are also held to additional requirements with regard to facility
construction. Paragraph (e)(3)(iii)(A) requires that the laboratory be
separated from areas that are open to unrestricted traffic flow within the
building. Passage through two sets of self-closing doors is the requirement
for entry into the work area from access corridors or other contiguous areas.
This type of entrance reduces the likelihood of untrained employees
accidentally entering the work area, since such entry necessitates deliberate
action on the part of the individual. Paragraph
(e)(3)(iii)(B) requires that windows in the laboratory be closed and sealed. This
helps assure containment of any aerosols and helps maintain proper operation
of biosafety cabinets through minimization of cross drafts. Paragraph
(e)(3)(iii)(C) requires that a ducted exhaust air ventilation system shall be
provided which creates directional airflow that draws air from clean areas
into the laboratory toward contaminated areas. The proper direction of the airflow
shall be verified (i.e., into the work area) by the employer at least every
six months. The exhaust air shall not be recirculated to any other area of
the building, shall be discharged to the outside, and shall be dispersed away
from occupied areas and air intakes. The requirement that research
laboratories have verified directional airflow into the work area is to
assure that air is drawn into the laboratory toward contaminated areas to
assist in maintaining containment of aerosols within the laboratory. Paragraph
(e)(3)(iii)(D) requires that the HEPA-filtered exhaust from Class 2 or 3
biosafety cabinets is to be discharged to the outside of the building or
through the building exhaust system. If it is discharged through the building
exhaust system, it must be connected to this system in a manner that avoids
any interference with the air balance of the cabinets or the building exhaust
system. This is required to assure that biosafety cabinets and the building
exhaust system continue to function as intended. Paragraph
(e)(3)(iii)(E) requires that continuous flow centrifuges or other equipment
that may produce aerosols must be contained in devices that exhaust air
through a HEPA filter before discharge into the laboratory. This assures that
any aerosols which may contain M. tuberculosis are effectively
filtered from the exhaust air before discharge into the laboratory, thereby
protecting employees against inadvertent exposure. All
of the requirements discussed above were derived directly from the CDC/NIH's
"Biosafety in Microbiological and Biomedical Laboratories." OSHA
requests comment on the applicability and OSHA's application of CDC/NIH's
guidelines for their use in laboratories which handle M. tuberculosis. Paragraph (f) Respiratory Protection Respirators
serve as supplemental protection to reduce employee exposures when
engineering and work practice controls are not sufficient to provide adequate
protection against airborne contaminants. At
the opening of the public hearings for the revision of OSHA's General
Industry Respiratory Standard, 29 CFR 1910.134, the Agency stated that all
aspects of respirator use for protection against tuberculosis would be
addressed in the rulemaking for Occupational Exposure to Tuberculosis. Consequently,
the respiratory protection portion of this proposal contains all of the
respiratory protection provisions that have been preliminarily determined to
be applicable to respirator use for TB. In the past, OSHA standards have
referred to the Respirator Standard (29 CFR 1910.134) for the general
requirements for respirator use (e.g., written respiratory protection
program; respirator maintenance) and have included only the respirator
provisions specific to the hazard addressed by the standard. OSHA's approach
in this proposal, however, is to include provisions relative to all aspects
of respirator use for tuberculosis. This will provide interested parties with
the opportunity to review and comment on these aspects. To assure consistency
across OSHA respiratory protection standards, however, OSHA is considering
including in the final TB rule cross-referencing to the general requirements
of the Respiratory Protection Standard (29 CFR 1910.134) and retaining in the
final TB rule only those provisions specific to respirator use for TB. OSHA
seeks comment on this intended approach in the final standard for TB. Paragraph
(f)(1)(i) states that each employer must provide a respirator to each
employee who: (A) enters an AFB isolation room or area in use for TB
isolation; (B) is present during performance of procedures or services for an
individual with suspected or confirmed infectious TB who is not masked; (C)
transports an individual with suspected or confirmed infectious TB in an
enclosed vehicle or who transports an individual with suspected or confirmed
infectious TB within the facility whenever that individual is not masked; (D)
repairs, replaces, or maintains air systems or equipment that may reasonably
be anticipated to contain aerosolized M. tuberculosis; (E) is working
in an area where an unmasked individual with suspected or confirmed
infectious TB has been segregated or otherwise confined (e.g., while
awaiting transfer), and (F) is working in a residence where an individual
with suspected or confirmed infectious TB is known to be present. In
addition, paragraph (f)(1)(ii) requires that each employer who operates a
research laboratory provide a respirator to each employee who is present when
aerosols of M. tuberculosis cannot be safely contained. In
discussing the use of respiratory protection in their guidelines, CDC states: Personal
respiratory protection should be used by (a) persons entering rooms where
patients with known or suspected infectious TB are being isolated, (b)
persons present during cough-inducing or aerosol-generating procedures
performed on such patients, and (c) persons in other settings where
administrative and engineering controls are not likely to protect them from
inhaling infectious airborne droplet nuclei. These other settings include
transporting patients who may have infectious TB in emergency transport
vehicles and providing urgent surgical or dental care to patients who may
have infectious TB before a determination has been made that the patient is
noninfectious. (Ex. 4B) The
guidelines also state that respiratory protection should be worn by personnel
who are performing maintenance and testing procedures on HEPA filtration
systems (Ex. 4B). Furthermore, the CDC/NIH document "Biosafety in
Microbiological and Biomedical Laboratories" recommends that respiratory
protection be worn whenever aerosols of organisms such as M. tuberculosis
cannot be safely contained (Ex. 7-72). Consequently, employees who may need
to wear respirators could include not only health care providers but also
employees such as housekeepers, dietary personnel, laboratory technicians,
employees in intake areas, maintenance personnel, social workers, and so
forth. It is the employer's responsibility to determine which occupationally
exposed employees would be covered under this provision and, therefore, would
need to wear a respirator. With
regard to utilization of respiratory protection when entering an AFB
isolation room or area, the reader is referred to the definition of "AFB
isolation room or area" in paragraph (j), Definitions. This definition
clarifies that the requirement refers not only to situations such as entering
a patient room occupied by an individual with suspected or confirmed
infectious TB but also refers to entering any area where high-hazard
procedures are being performed and entering an autopsy room where M.
tuberculosis may be aerosolized. Paragraph
(f)(1)(i)(B) requires respirator use when an employee is present during
performance of procedures or services for an unmasked individual with
suspected or confirmed infectious TB. This provision is intended to cover
those situations in which a procedure or service is performed outside of an
AFB isolation room or area. For example, a facility may not have a portable
X-ray and may, therefore, perform this procedure in a standard X-ray room. If
the individual is not masked in such a situation, all employees present
(i.e., the X-ray technician and any other employees in the room) must utilize
respiratory protection. As
stated previously under discussion of Scope, employees rendering emergency
medical services may spend time in very close proximity to individuals with
suspected or confirmed infectious TB within an enclosed vehicle. Even though
the individual may be masked, droplet nuclei that escape capture in the mask
are contained within the vehicle, thereby increasing the likelihood that
employees will breathe droplet nuclei generated when the patient coughs or
speaks. In addition, under paragraph (f)(1)(i)(D), employees who repair,
replace, on maintain air systems or equipment that may reasonably be
anticipated to contain aerosolized M. tuberculosis are at risk of
occupational exposure as a result of exposure to air that could contain
aerosolized bacilli. Therefore, respirator use would be required in this
situation. As
discussed under Scope, aerosolized M. tuberculosis is a recognized
hazard to laboratory personnel. When aerosols of M. tuberculosis
cannot be safely contained, such as during a spill, the employer is required
to provide a respirator to each employee who is present during this time. This
is consistent with CDC/NIH recommendations regarding respirator use in
research laboratories (Ex. 7-72). Unlike
some other airborne contaminants, the quantity of M. tuberculosis
that, when inhaled, will result in infection (i.e., infectious dose) has not
been determined conclusively. The number of droplet nuclei expelled into a
room by an infectious individual or aerosol-producing procedure and the
concentration of droplet nuclei in a room or area are unknown. Consequently,
there is no basis to judge the effectiveness of other control measures
present even though they may be operating as intended. OSHA therefore agrees
with the CDC that, in the above situations, other controls that may be in
place cannot be assumed to adequately protect employees against exposure to
airborne TB droplet nuclei and therefore that the use of respiratory
protection is necessary. While
OSHA agrees with and has adopted most of the CDC's recommendations regarding
when respiratory protection is necessary, the Agency has extended respirator
use to two additional situations. More specifically, when an individual with
suspected or confirmed infectious TB is not masked and is transported within
a facility, the employee transporting the individual must wear a respirator. While
CDC recommends masking individuals with suspected or confirmed infectious TB
prior to transporting them, there may be special circumstances in which the
individual may not be masked (e.g., individual is combative and will
not wear a mask). The employee transporting the individual would most likely
spend an extended period of time in close proximity to the individual, either
walking beside or behind (e.g., pushing a wheelchair) the individual. The
employee would, therefore, be walking directly through the airspace into
which the individual would be expelling droplet nuclei, receiving exposure
each time the individual coughed, resulting in multiple relatively
concentrated exposures. In view of this, the latter portion of paragraph
(f)(1)(i)(C) addresses the Agency's belief that it is necessary and justified
that respiratory protection be worn by the employee to protect against
occupational exposure if the individual is not masked. The
second situation, under paragraph (f)(1)(i)(E), requires respirator use by an
employee when working in an area where an unmasked individual with suspected
or confirmed infectious TB has been segregated or otherwise confined, for
example while awaiting transfer. As discussed above, it is assumed that such
individuals would normally be masked. Here again, however, there may be
circumstances that preclude the individual from being masked (e.g.,
the individual is combative). Therefore, employees who must work in the area
where these unmasked individuals are located, whether working directly with
the individual or performing other duties, must wear a respirator to protect
against possible tuberculosis infection. Paragraph
(f)(1)(i)(F) requires that a respirator be worn by an employee who is working
in a residence where an individual with suspected or confirmed infectious TB
is known to be present. In this situation, whether the individual is masked
or unmasked does not trigger respirator use since the individual has been
releasing droplet nuclei into the residence airspace. The CDC refers to this
type of situation in its discussion of the provision of home health care and
states: <<Health care workers>> who provide medical services in
the homes of patients who have suspected or confirmed infectious TB should
instruct such patients to cover their mouths and noses with a tissue when
coughing or sneezing. Until such patients are no longer infectious, HCWs
should wear respiratory protection when entering these patients' homes. (Ex.
4B) In
addition to home health care and home-based hospice care workers, other
employees, such as social workers who are entering these residences, would
come under this provision. It is the Agency's intent that a respirator be
used by an employee in these situations for the time that the employee is in
the residence and that respirator use continue until the individual is
noninfectious. The
proposed standard, in paragraphs (f)(1)(iii) and (f)(1)(iv), places several
general responsibilities upon the employer regarding respiratory protection. Paragraph
(f)(1)(iii) states that where respirators are required by the standard, the
employer shall provide them at no cost to the employee and assure that they
are used in accordance with the requirements of the standard. Paragraph
(f)(1)(iv) stipulates further that the employer must assure that the employee
dons a respirator before entering the work settings or performing the tasks
set forth in paragraphs (f)(1)i and (f)(1)(ii) above and uses it until
leaving the work setting or completing the task, regardless of other control
measures in place. It
has been OSHA's long-standing policy to hold the employer responsible for
controlling exposure to hazards in his or her workplace and to fulfill this
responsibility at no cost to the employee. Therefore, the financial burden
for purchasing and providing personal protective equipment, including
respirators, rests upon the employer just as it does for all other control
measures (e.g., engineering controls). OSHA believes that in order to
assure that employees are adequately protected, the employer has the
responsibility not only to provide respiratory protection, but also to assure
that it is utilized when necessary. Furthermore, respiratory protection must
be donned prior to entering the above work settings or performing the tasks,
for the period of time that the employee remains in these work settings, and
must not be removed until the employee leaves the work setting or completes
the tasks. In this way, the employee is protected for the entire period of
occupational exposure. It
is not OSHA's intent that each employee be monitored constantly for
compliance; however, the Agency does believe that the employer has the power
to assure that employees follow specific rules. For example, most employers
have requirements that they require employees to follow, such as reporting to
work on time, working a minimum number of hours per day, notifying the
employer when the individual is unable to report for work, and taking certain
precautions to prevent nosocomial infections. Following these requirements is
not left to the employee's discretion, and employers generally have some
process to ensure conformance with these procedures. Therefore, the Agency
believes that the employer has not only the responsibility, but also the
ability, to assure that respiratory protection is used in accordance with the
requirements of this section. Paragraph
(f)(2)(i) requires that each employer who has any employee whose occupational
exposure is based on entering any of the work settings or performing any of
the tasks described in paragraph (f)(1) must establish and implement a
written respiratory protection program that assures that respirators are
properly selected, fitted, used, and maintained. The program must include the
following elements: (A) Procedures for selecting respirators for use in the
work setting; (B) a determination of each employee's ability to wear a
respirator, as required under paragraph (g)(3)(ii), Medical Surveillance, for
each employee required to wear a respirator; (C) procedures for the proper
use of respirators; (D) fit testing procedures for tight-fitting respirators;
(E) procedures and schedules for cleaning, disinfecting, storing, inspecting,
repairing, or otherwise maintaining respirators; (F) training of employees to
assure the proper use and maintenance of the respirators as required under
paragraph (h), Communication of Hazards and Training; and (G) procedures for
periodically evaluating the effectiveness of the program. Written standard
operating procedures are essential to an effective respiratory protection
program. Developing and writing down standard operating procedures require
employers to think through how all of the requirements pertaining to
respirators will be met in their workplace. In addition, this provision
assures that the employer establishes standardized procedures for selecting,
using, and maintaining respirators in the workplace. OSHA's long-standing
position has been that a systematic respiratory protection program is
necessary to provide for consistency in protection. Guidance that has been
developed by an outside party (e.g., a respirator manufacturer) on the
general use of a particular respirator would not address the site-specific
aspects of the employer's work setting and would not be an appropriate
substitute for a respiratory protection program. Paragraph
(f)(2)(ii) requires the employer to designate a person qualified by
appropriate training or experience to be responsible for the administration
of the respiratory protection program and for conducting the required
periodic evaluations of its effectiveness. To assure that the integrity of
the respiratory protection program is maintained through the continuous
oversight of one responsible individual, OSHA is proposing that a qualified
person be designated as responsible for the administration of the program. That
individual can work with a committee or assign responsibility for portions of
the program to other personnel, but the overall responsibility for the operation
of the program remains with the designated person. This approach ensures
coordination of all facets of the program. The level of training or
experience necessary for a designated person has been left performance
oriented since this will vary with the complexity of the respirator program. However,
the person chosen would need to have sufficient knowledge of respiratory
protection and the workplace to properly supervise the program. Employers
are required, in paragraph (f)(2)(iii), to review and update the written
program as necessary to reflect current workplace conditions and respirator
use. Reviewing and updating will assure that the program addresses current
conditions. The reason OSHA has not set a schedule for reviewing the program
is because conditions may change frequently in some work settings while
remaining relatively stable in others. Thus, the employer determines the
frequency of the review. However, when an employer is aware of changes in the
workplace or respirator use which could necessitate changes in the written
program, it is not appropriate to delay revising the written program. OSHA's
use of the phrase "as necessary" in the requirement is intended to
assure that such changes are incorporated into the written program
expeditiously. As the workplace situation or respirator use changes, the
program is to be revised. In addition, paragraph (f)(2)(iv) requires that
employers, upon request, make the written respiratory protection program
available to affected employees, their designated representatives, the
Assistant Secretary, and the Director. This provision also requires that a
copy of the program be submitted to the Assistant Secretary and/or the
Director, if requested. Paragraph
(f)(3) sets out the respirator characteristics that must be satisfied in
order to provide employees with a respirator that will protect them against
aerosolized M. tuberculosis. These criteria are presented in
performance-oriented language to provide flexibility in choice of respirators
and have been drawn from CDC recommendations (Ex. 4B). CDC has based these
criteria on currently available information relative to respirators that
includes: *
* * (a) data on the effectiveness of respiratory protection against
noninfectious hazardous material in workplaces other than health-care
settings and on an interpretation of how these data can be applied to
respiratory protection against M. tuberculosis; (b) data on the
efficiency of respirator filters in filtering biological aerosols; (c) data
on face-seal leakage; and (d) data on the characteristics of respirators that
were used in conjunction with administrative and engineering controls in
outbreak settings where transmission to HCWs and patients was terminated (Ex.
4B). The
CDC Guidelines go on to state: Available
data suggest that infectious droplet nuclei range in size from 1 [micron] to
5 [microns]; therefore, respirators used in health-care settings should be
able to efficiently filter the smallest particle in this range. Fifty liters
per minute is a reasonable estimate of the highest airflow rate an HCW is
likely to achieve during breathing, even while performing strenuous work
activities (Ex. 4B). In
their 1994 TB guidelines, the CDC states: Respiratory
protective devices used in health-care settings for protection against M.
tuberculosis should meet the following standard performance criteria: 1.
The ability to filter particles 1 um in size in the unloaded state with a
filter efficiency of < 95 % (i.e., filter leakage of < 5
%), given flow rates of up to 50 L per minute. 2.
The ability to be qualitatively or quantitatively fit tested in a reliable
way to obtain a face-seal leakage of < 10 %. 3.
The ability to fit different facial sizes and characteristics of HCWs [<<health care
workers>>],
which can usually be met by making the respirators available in at least
three sizes. 4.
The ability to be checked for facepiece fit, in accordance with standards
established by the Occupational Safety and Health Administration (OSHA) and
good industrial hygiene practice, by HCWs each time they put on their
respirators. (Ex. 4B) The
various respirator provisions that OSHA is proposing rely heavily on the
CDC's aforementioned respirator performance criteria. The second, third, and fourth
CDC criteria are addressed by paragraphs (f)(3)(i) (A) and (B) and paragraph
(f)(5)(ii). Paragraph (f)(3)(i) requires the employer to select and provide
properly fitted negative pressure or more protective respirators. Negative
pressure respirators must be capable of being: (A) Qualitatively or
quantitatively fit tested in a reliable way to verify a face-seal leakage of
no more than 10 %; and (B) fit checked by the employee each time the
respirator is donned. Paragraph (f)(5)(ii) requires that employers assure
that each employee who must wear a tight-fitting respirator is fit tested and
passes the fit test. All of these provisions deal with the ability of the
respirator to achieve a good face seal with a particular employee. Good
face fit is critical in assuring proper performance of respiratory
protection. When an employee inhales through a respirator that does not fit
properly, contaminated workplace air can enter the respirator through gaps
and leaks in the seal between the face and the facepiece. OSHA is requiring
the employer to provide each employee who must wear a respirator with one
that fits. To do so, the employer will have to consider the facial sizes and
characteristics in his or her workplace. It is not necessary for the employer
to have respirators of different sizes of characteristics unless the
employees need them. In other words, an employer may need only one or two
styles and sizes. However, in workplaces where employees have different
facial sizes and characteristics, obtaining proper respirator fit for each
employee may require the fit testing of different mask sizes, possibly from
several manufacturers. Proper respirator fit reduces inhalation leakage
through the face-to-facepiece seal to a minimum. Once
a respirator has been selected based on its ability to achieve an adequate
face-to-facepiece seal, the employee must be able to check that the
respirator is properly seated and sealed to his or her face each time it is
donned. The respirator, therefore, must be able to be fit checked by the
employee. This is a procedure in which the employee covers the filter surface
of the respirator and inhales (negative fit check) and exhales (positive fit
check). If the respirator has an exhalation valve, this valve must be covered
during the positive fit check. A respirator that is properly sealed will
firmly adhere to the wearer's face upon inhalation due to the negative
pressure created inside the mask. Upon exhalation, the mask should lift
slightly off of the wearer's face to allow air to escape around the face
seal. Employers should be aware that a problem could exist with fit checking
some disposable negative pressure respirators. That is, it is difficult to
cover the entire filter surface, thereby hindering the employee's ability to
perform a proper fit check. At least one respirator manufacturer has
developed a "fit-check cup" that covers the filter surface of their
disposable respirator, thereby permitting the user to more easily perform a
fit check. Reusable elastomeric facepiece respirators utilize filter
cartridges that can be covered for performing a fit check. CDC's
first criteria, regarding filter efficiency, is addressed under paragraph
(f)(3)(ii) of the standard. This provision requires the employer to select a
respirator that will function effectively in the conditions of the work
setting. In addition to meeting the criteria in paragraph (f)(3)(i) above,
the respirator shall be, at a minimum, either a High Efficiency Particulate
Air (HEPA) respirator selected from among those jointly approved as
acceptable by the Mine Safety and Health Administration (MSHA) and by the
National Institute for Occupational Safety and Health (NIOSH) under the
provisions of 30 CFR part 11, or an N95 respirator certified by NIOSH under
the provisions of 42 CFR part 84. NIOSH
and MSHA are the government agencies charged with testing and certifying
respiratory protective devices. It has always been OSHA's policy that
respiratory protection must be certified by these agencies before being
deemed acceptable. Until recently, HEPA respirators were the only NIOSH
certified negative pressure respirators that met the CDC's filter efficiency
criteria. However, on July 10, 1995, NIOSH's original respirator
certification procedures for air-purifying particulate respirators, 30 CFR
part 11, were replaced by revised procedures, 42 CFR part 84 (Ex. 7-261). Under
the new procedures, all nonpowered air-purifying particulate respirators are
challenged with a 0.3 micron particle (the most penetrating size) at a flow
rate of 85 liters per minute. At the conclusion of the test, those
respirators that pass are placed into one of nine classes of filters (three
levels of filter efficiency, with three categories of resistance to filter
efficiency degradation). The three levels of filter efficiency are 99.97 %,
99 %, and 95 %. The three categories of resistance to filter efficiency
degradation are labeled N (not resistant to oil), R (resistant to oil), and P
(oil proof). Given these categories, a type N95 respirator would meet or
exceed the filter efficiency performance criteria set forth in the CDC
guidelines which state that a respirator appropriate for use in protecting
against transmission of tuberculosis must be able to filter particles 1
micron in size in the unloaded state with a filter efficiency of ?95 %, given flow rates up to 50 liters per
minute (Ex. 4B). The underlying reasoning for the acceptability of type N95
respirators is that their filter efficiency of >95 % for a 0.3
micron particle will exceed 95 % filtering efficiency for a particle three
times as large (i.e., 1 micron). Also, the Agency assumes that oil aerosols
are not likely to be found in the work settings covered by the standard, and
therefore, that the use of a category N respirator would be sufficient. However,
if oil aerosols are present, the employer would be expected to consider this
when selecting the category of respirator to be used in his or her workplace. OSHA
is permitting the employer to select either a HEPA respirator certified under
30 CFR part 11 or a respirator certified under 42 CFR part 84, since
particulate respirators certified under both of these regulations are
currently on the market. HEPA respirators are the only nonpowered particulate
respirators certified under 30 CFR part 11 that meet the CDC guidelines
filtration criteria. However, applications for certification of nonpowered
particulate respirators under 30 CFR part 11 are no longer being accepted by
NIOSH. Therefore, dwindling stocks of HEPA respirators certified under that
regulation will eventually lead to their unavailability, and employers will
of necessity be selecting respirators from those approved under 42 CFR part
84. Paragraph
(f)(4)(i) states that the employer shall not permit any respirator that
depends on a tight face-to-facepiece seal for effectiveness to be worn by
employees having any conditions that prevent such a seal. Examples of these
conditions include, but are not limited to, facial hair that comes between
the sealing surface of the facepiece and the face or facial hair that
interferes with valve function, absence of normally worn dentures, facial
scars, or headgear that projects under the facepiece seal. Paragraph
(f)(4)(ii) requires the employer to assure that each employee who wears
corrective glasses or goggles wears them in such a manner that they do not
interfere with the seal of the facepiece to the face of the wearer. Tight-fitting
facepiece respirators rely on a good face-to-facepiece seal in order to
achieve effective protection. Therefore, the employer must not allow
employees to wear such respirators with conditions that prevent such a seal. Several
studies support the prohibition of facial hair that comes between the sealing
surface of the facepiece and the face (Exs. 7-243, 7-242, 7-182). A study by
Skretvedt and Loschiavo found that bearded subjects wearing half-mask
respirators had a median face seal leakage 246 times greater than clean
shaven subjects. They go on to state: Even
though a number of bearded individuals did obtain fit factors above OSHA's
minimum requirement for half-mask respirators, they all failed the
qualitative fit test. No relationship was found between the length, shape,
density and texture of beards and the amount of face seal leakage. Therefore,
the only way to identify bearded negative-pressure respirator wearers
obtaining fit factors above OSHA's minimum requirements would be by
performing a quantitative fit test on them. However, even if quantitative fit
tests are performed on all bearded individuals, another problem must be
faced. The drop in the fit factor experienced when a beard is present is of
such magnitude that no confidence can be placed in the protection the
respirator will provide in the workplace or in future donnings. All
respirator users experience variability from one donning to the next. This
fit variability from donning to donning occurs due to changes in strap
tension, positioning on the face, and a host of other variables. Donning-to-donning
fit variability for bearded individuals will be even greater since additional
variables will be introduced. A beard is a dynamically changing thing. The
hair length constantly changes as well as the orientation of the hair in the
sealing surface. Beards also accumulate moisture, natural oils, and debris
from the workplace. Even though a percentage of bearded respirator wearers
obtain fit factors slightly above OSHA's minimum requirements, the tremendous
drop in fit factor resulting from the presence of a beard is such that the
safety factor necessary to accommodate the variability of fit no longer
exists. In summary, although bearded individuals may be able to achieve fit
factors above OSHA's minimum requirements during a specific quantitative fit
test, the drop in protection caused by a beard coupled with the large fit
variability from donning to donning makes it quite likely that the individual
will not obtain the minimum required protection in the workplace. (Ex. 7-243) Therefore,
while a bearded respirator wearer may be able to obtain a satisfactory fit on
a particular occasion, one cannot assume that the individual can reliably be
expected to achieve that same protection level each time the respirator is
used. Beards grow and change daily. Each time a respirator is donned there is
fit variability. Such variability in face seal is greatly increased for
bearded workers. This large variability in fit means that a reliable seal
cannot be reasonably expected. This provision should not be construed as a
blanket prohibition on beards among respirator wearers. There are other types
of respiratory equipment such as hoods, helmets and suits that can be worn by
employees with beards, since they do not rely upon a tight facepiece fit. In
addition, this provision refers to facial hair that interferes with the
facepiece seal rather than simply growth of beard or sideburns. It is the
interference with the facepiece seal that is the concern, not the presence of
facial hair. Other conditions such as the absence of normally worn dentures,
facial scarring and cosmetic surgery change the geometry of the face, thereby
changing the ability of the respirator wearer to achieve a facepiece seal. Facepiece
seal may also be compromised when headgear, temple pieces and nose pieces of
glasses, the edges of goggles and so forth project underneath the
respirator's sealing surface. Both of the above provisions are intended to
eliminate or minimize conditions that jeopardize face-to-facepiece seal and
could permit leakage of outside air into the facepiece. Paragraph
(f)(4)(iii) states that disposable respirators must be discarded when
excessive resistance, physical damage, or any other condition renders the
respirator unsuitable for use. It is not expected that the filter media of
respiratory protective devices would become occluded with particulates in the
work settings covered by this standard. However, if excessive resistance is
noted, the respirator must be discarded. Also, such respirators must be
structurally sound in order to provide a proper face seal and maintain their
effectiveness. Whenever physical damage occurs (e.g., the respirator
is crumpled or torn; the flexible face seal is damaged; a head strap is
broken), effective functioning cannot be assured and the respirator must be
replaced. In addition, other conditions may render the respirator unsuitable
for use (e.g., the respirator may become contaminated with blood),
thereby requiring discard. In
view of the types of activities carried out and the environmental conditions
encountered in the work settings covered by this standard, OSHA is proposing
to allow the multiple use of disposable respirators. However, this action
should in no way be construed as setting a precedent for the use of
disposable respirators in any other OSHA standards or in how OSHA views
multiple use of disposable respirators in other work settings. OSHA requests
comment on the approach taken in this proposal toward the reuse of disposable
respirators. Paragraph
(f)(4)(iv) requires the employer to assure that each employee, upon donning a
tight-fitting respirator, performs a facepiece fit check prior to entering a
work area where respirators are required. In performing the fit check, the
procedures in Appendix B or other procedures recommended by the respirator
manufacturer that provide equivalent protection to the procedures in Appendix
B must be used. This provision is supported by a recent study by Meyers et
al. that concluded: *
* * for wearers of respirators that have been properly fit by a recognized
fit test, conducting fit checks according to the manufacturer's instructions
can be a useful tool for more consistently maintaining the quality of
respirator donning. (Ex. 7-233) The
use of such seal checks are a way of helping to assure that attention is paid
to obtaining an adequate facepiece seal each time a respirator is used. The
standard requires, under paragraph (f)(4)(v), that respirators be immediately
repaired, or discarded and replaced when they are no longer in proper working
condition. Examples of these changes in condition would be that a strap has
broken, the respirator has lost its shape, or the face seal can no longer be
maintained. As discussed above, respirators must be in good working condition
in order to function effectively. Therefore, it is imperative that they not
be used if they have been impaired in any way. The respirator manufacturers
can supply replacement parts for damaged portions of their elastomeric
respirators. Disposable respirators cannot be repaired and must be discarded
when damaged. Paragraph
(f)(4)(vi) stipulates that the employer shall permit each employee to leave
the respirator use area as soon as practical to: (A) change the filter
elements or replace the respirator whenever the ability of the respirator to
function effectively is compromised or the employee detects a change in
breathing resistance; or (B) wash his or her face and respirator facepiece as
necessary to prevent skin irritation associated with respirator use. This
provision encourages and facilitates the proper use of respirators by
employees by authorizing employees to take specific actions to assure the
effective functioning of their respirators. This provision is consistent with
requirements in other health standards (e.g., Lead, 29 CFR 1910.1025;
Cadmium, 29 CFR 1910.1027). Considering
the health problems that may be exacerbated with respirator use and their
associated detrimental effects on an employee, the proposal states in
paragraph (f)(4)(vii) that each employee required to wear a respirator under
this section shall be evaluated in accordance with paragraph (g), Medical
Surveillance, of this section to determine whether any health conditions
exist that could affect the employee's ability to wear a respirator. In
addition, paragraph (f)(4)(viii) states that no employee shall be assigned a
task requiring the use of a respirator if, based upon the employee's most
recent evaluation, the physician or other licensed health care professional,
as appropriate, determines that the employee will be unable to continue to
function adequately while wearing a respirator. If the physician or other licensed
health care professional, as appropriate, determines that the employee's job
activities must be limited, or that the employee must be removed from the
employee's current job because of the employee's inability to wear a
respirator, the limitation or removal shall be in accordance with paragraph
(g)(5)(iii) under Medical Removal Protection of this section. Common
health problems that could interfere with respirator use include
claustrophobia (an intolerance of feeling enclosed and a subjective feeling
of breathing difficulty), chronic rhinitis, nasal allergies that would
necessitate frequent removal of the respirator to deal with nasal discharges,
and chronic sinusitis. In addition, difficulties with the use of respirators
may arise in employees with respiratory or cardiac diseases. Respiratory
diseases include chronic obstructive pulmonary disease, emphysema, asthma,
and moderate to severe pneumoconiosis. Cardiac or cardiorespiratory diseases
that may affect respirator wear include any type of congestive heart disease,
other ischemic heart diseases, and hypertension. As
discussed further under paragraph (g)(5)(iv), Medical Surveillance, of this
section, employees who are removed from work due to the inability to wear a
respirator are afforded certain medical removal protection relative to
retention of earnings, seniority, rights and benefits. The Agency believes
that these provisions will encourage all employees, including those
experiencing difficulty with respirator use, to participate in the Medical Surveillance
Program and will minimize an employee's fear of losing his or her job due to
the possible inability to wear a respirator. Paragraph
(f)(5)(i) requires the employer to perform either quantitative or qualitative
face fit tests in accordance with the procedures outlined in Appendix B of
this section. Quantitative
fit testing is an assessment of the adequacy of respirator fit by numerically
measuring the amount of leakage into the facepiece. One method of
accomplishing this assessment utilizes a procedure whereby the level of
penetration of a test agent of a known concentration is measured inside the
facepiece of the respirator. In this quantitative fit test procedure, the
respirator is worn in a stable test atmosphere containing a suitable
challenge agent. The adequacy of fit is determined by measuring the actual
levels of the challenge agent, both outside and inside the facepiece of the
respirator. This provides a quantitative assessment of the fit (the fit
factor). Fit testing allows the employer to continue testing different
facepieces until a properly fitting respirator is identified and selected for
the employee. Quantitative fit testing requires the use of moderately
sophisticated testing equipment and is more expensive to perform than
qualitative fit testing, which may reduce its availability in some work
sites. Also, testing services may not be available in all parts of the
country to provide quantitative fit testing services for small businesses. Qualitative
fit testing does not provide a numerical measure of the quality of the fit
but simply determines whether a respirator fits or not. The outcome of the
test is simply a pass or fail result. Qualitative fit testing involves the
detection of a gas, vapor, or aerosol challenge agent through subjective
means such as odor, taste, or nasal irritation. If the challenge agent's
presence is detected, the respirator fit is considered to be inadequate. Qualitative
fit testing is more subjective than quantitative testing because it depends
on the individual's ability to detect the test agent. OSHA
believes that while quantitative fit testing has some advantages, qualitative
fit testing conducted in accordance with the protocols described in Appendix
B of this section can generally accomplish the intent of the standard, which
is to assure that each employee is assigned and wears a respirator that
provides a proper fit. Paragraph
(f)(5)(ii) states that the employer shall assure that each employee who must
wear tight-fitting respirator passes a fit test: (A) at the time of initial
fitting; (B) whenever changes occur in the employee's facial characteristics
that affect the fit of the respirator; (C) whenever a different size or make
of respirator is used; and (D) at least annually thereafter unless the annual
determination required under paragraph (g)(3)(ii)(A), Medical Surveillance,
indicates that the annual fit test of the employee is not necessary. This
frequency of fit testing is necessary to assure that factors that may affect
the proper fit of a respirator are detected and necessary adjustments are
performed to assure the integrity of the faceseal. For example, the fit of
respirators is not standardized among manufacturers. Fit testing would be
required, therefore, whenever a different size or make of respirator is used.
In addition, a change in an employee's facial structure can compromise a
respirator's faceseal. Examples of such changes include loss of weight,
cosmetic surgery, facial scarring, and the installation of dentures or the
absence of dentures that are normally worn by the individual. Therefore, fit
testing is required when any facial changes, such as those mentioned above,
occur. Requiring
annual fit testing, unless the annual determination by the physician or other
licensed health care professional indicates that the annual fit test is not
necessary, assures that factors that could affect respirator fit are detected
and the employee's respirator is adjusted or replaced as necessary. It is
OSHA's intent in this provision that each employee be evaluated annually for
respirator fit. This can be accomplished through either an actual fit test or
through a person-to-person evaluation consisting of a questionnaire and
personal observation by the evaluator carried out under paragraph
(g)(3)(ii)(A), Medical Surveillance, of this section. It should be noted that
an annual determination of respirator fit is required, either through fit
testing or the person-to-person evaluation. The employer may use the
determination of the need for the annual fit test in lieu of an annual fit
test if that determination indicates that a fit test is not necessary. One
of the criteria that must be satisfied when selecting respirators is a
faceseal leakage of 10 % or less. OSHA considers any respirator that passes a
qualitative fit test to meet this criteria. However, quantitative fit testing
necessitates that a particular numerical value be achieved. Therefore,
paragraph (f)(5)(iii) requires that when quantitative fit testing is
performed, the employer shall not permit an employee to wear a tight-fitting
respirator unless a minimum fit factor of one hundred (100) is obtained in
the test chamber. This value corresponds to a faceseal leakage of 10 % or
less. In
order to assure that continuing protection is achieved by reusable and powered
air purifying respiratory protective devices, it is necessary to establish
and implement proper maintenance and care procedures. A lax attitude toward
this part of the respiratory protection program will negate successful
selection and fit because the devices will not deliver the assumed protection
unless they are kept in proper working order. A basic program for assuring
proper respirator function would contain procedures for cleaning, inspection,
repair, and replacement of respirators used in the workplace. Paragraph
(f)(6)(i) requires that the employer clean and disinfect the respirators
using the manufacturer's recommended procedures at the following intervals:
(A) as necessary for respirators issued for the exclusive use of an employee;
and (B) after each use for respirators issued to more than one employee. Respirators
that are not cleaned and disinfected can cause skin irritation and
dermatitis. When more than one employee uses the same respirator, cleaning
and disinfecting after each use provides the additional benefit of minimizing
the respirator's role as a vehicle for spreading infections (e.g.,
skin, respiratory) between employees. In
order to assure continued respirator reliability, they must be inspected on a
regular basis. Therefore, paragraph (f)(6)(ii) requires that respirators be
inspected before each use and during cleaning after each use. As stipulated
in paragraph (f)(6)(iii), such inspections must include: (A) a check of
respirator function, tightness of connections and condition of the facepiece,
head straps, valves, connecting tube, and cartridges, canisters, or filters;
and (B) a check of the rubber or elastomer parts for pliability and signs of
deterioration. In this way, the employer can assure that the respirator is
functioning as intended, is able to be adjusted by the user, will not allow
leakage through cracks or breaks in the respirator, and is pliable enough to
achieve a proper faceseal. The
standard also contains provisions regarding those respirators that are found
to be deficient upon inspection. Paragraph (f)(6)(iv) states that respirators
that fail to pass inspection must be removed from service and repaired or
adjusted in accordance with the following: (A) repairs or adjustments to
respirators are only to be made with NIOSH-approved parts designed for the
respirator by the respirator manufacturer and by persons appropriately
trained to perform such operations; (B) only repairs of the type and extent
covered by the manufacturer's recommendations may be performed; and (C)
reducing or admission valves or regulators shall be returned to the
manufacturer or given to an appropriately trained technician for adjustment
or repair. It is self-evident that repairs to respirators should only be
performed by trained individuals, using parts designed for the specific
respirator under repair (not all respirator designs are identical), and that
the individual should not attempt repairs that he or she is not qualified to
undertake or which are not recommended by the manufacturer. Another
important aspect of assuring appropriate respirator function is proper
storage. Therefore, paragraph (f)(6)(v) stipulates that the employer assure
that respirators are stored in a manner that protects them from
contamination, damage, dust, sunlight, extreme temperatures, excessive
moisture, damaging chemicals and that prevents deformation of the facepiece
or exhalation valve. Proper storage, of both new respirators and those
already in service, assists in maintaining appropriate respirator function by
minimizing conditions that may cause deterioration of the respirator or
filter, interfere with filter efficiency, change faceseal geometry, and
prevent sealing of valves against inhalation of contaminated air. As
discussed previously, OSHA accepts those respirators certified by MSHA and
NIOSH. Therefore, paragraph (f)(7)(i) requires that filters, cartridges, and
canisters used in the workplace are properly labeled and color-coded with the
NIOSH approval label as required by 30 CFR part 11 or 42 CFR part 84, whichever
is applicable, before they are placed into service. The employer must assure
that the existing NIOSH approval label on a filter, cartridge, or canister is
not intentionally removed, obscured, or defaced while it is in service in the
workplace, as required by paragraph (f)(7)(ii) of this section. Paragraph
(f)(8) requires the employer to review the overall respiratory protection
program at least annually, and conduct inspections of the workplace as
necessary to assure that the provisions of the program are being properly
implemented for all affected employees. The reason an employer must conduct
an annual review and inspections as necessary is because respirators are
utilized as supplemental and, in some instances, sole protection to prevent
transmission of infectious TB. Therefore, it is of primary importance to
assure proper implementation of the program. The review of the program must
include an assessment of each element required under paragraph (f)(2) of this
section. Once the respiratory protection program is implemented, the employer
retains responsibility for detecting and addressing problems that arise. While
the written respiratory protection program is required to be reviewed and
updated under paragraph (f)(2)(iii) of the standard, the overall review
requires that the employer evaluate actual implementation in the workplace. Consequently,
this provision stipulates inspections of the workplace and an assessment of
each element required under paragraph (f)(2) of this section to assure proper
implementation of the program. OSHA
believes that the proposed provisions regarding respirators are both
appropriate and justified. OSHA seeks comments and data on all aspects of the
proposed respirator requirements. Paragraph (g) Medical Surveillance (1)
General The
purpose of this section is early detection and prevention of disease through
employee medical histories and physical examinations, TB skin testing,
medical management and follow-up of exposure incidents and skin test
conversions, and medical removal of employees with suspected or confirmed
infectious TB. These requirements are designed to ensure early detection of
TB infections and disease by providing appropriate medical examinations to
enable identification of infection or disease and to minimize the spread of
TB to other employees in the workplace. Additionally, there are requirements
in this section to assure that employees required to wear respiratory
protection are evaluated to determine their ability to wear a respirator and
advised about the need for annual fit testing. The needs of employees who
have health conditions that might require special attention are also
addressed (e.g., anergy testing, more frequent screening, or further
medical examinations to diagnose TB). Paragraph
(g)(1) calls for medical surveillance to be provided for each employee who
has occupational exposure, as defined in this standard. Occupational exposure
may result in TB infection and the subsequent development of TB disease. Paragraphs
(c)(1)(i, ii), (exposure determination) require the employer to identify
employees with occupational exposure in the facility. These employees must be
offered medical surveillance. OSHA
believes that early detection and management of exposed employees helps
prevent severe illness and death. According to CDC's 1994 edition of the Core
Curriculum on Tuberculosis (Ex. 7-93), approximately ten percent of the
persons infected will develop active TB disease at some point in their lives
(Exs. 4B, 7-50, 7-93). Five per cent of those infected develop disease within
the first two years following infection and another five percent develop
disease later in their lives. Immunosuppressed persons are at a considerably
greater risk of developing active disease following a TB infection. For
example, individuals infected with HIV and TB have been estimated to have a
8-10 % risk per year of developing active disease (Ex. 7-50). However,
according to the American Thoracic Society: Clinical
trials have shown that daily isoniazid preventive therapy for 12 months will
reduce the risk of developing tuberculosis in infected persons by about 70
percent and in over 90 percent of patients who are compliant in taking the
medications. (Ex. 5-80) Most
infected people have a positive reaction to the TB skin test within 2-10 weeks
after exposure. Consequently, early detection of newly infected workers is
critical as it permits early initiation of appropriate therapy and results in
a decrease in morbidity and mortality. Paragraph
(g)(1)(ii) requires that information about the signs and symptoms of
pulmonary tuberculosis disease, a medical history, a physical examination, TB
skin testing, medical management and follow-up, and if indicated, other
related tests and procedures and medical removal protection if the employee
develops infectious TB, be provided to each employee in work settings
described in paragraph (a) Scope who sustains an "exposure
incident." This provision is applicable when the employee has not been
categorized as having occupational exposure in the employer's Exposure
Control Plan. OSHA recognizes that there may be times when employees who are
not "reasonably anticipated" to have occupational exposure to TB
may be exposed, (e.g., if engineering controls break down or an
individual with infectious tuberculosis is unidentified during intake
procedures). Employees exposed under such circumstances incur the risk of TB
infection and subsequent disease (Ex. 7-93) as a result of their work duties.
OSHA includes this provision so that these employees are provided protection. Paragraph
(g)(1)(iii)(A) requires the employer to provide all medical surveillance at
no cost to the employee. This is consistent with OSHA policy. Providing
services at no cost to the employee is an important factor in successful
workplace health and safety programs because it encourages employee
participation in medical surveillance programs. Paragraph
(g)(1)(iii)(B) requires that all medical surveillance be provided at a
reasonable time and place for the employee. Convenience of these procedures
increases the likelihood of employee participation in the program. This helps
assure that employees receive the full benefits provided by the standard. OSHA
recognizes the need for this provision and has included it in other standards
(e.g., Ethylene Oxide, 29 CFR 1910.1047; Asbestos, 29 CFR 1910.1001;
and Bloodborne Pathogens 29 CFR 1910.1030). Paragraph
(g)(1)(iii)(C) states that all medical surveillance is required to be
performed by or under the supervision of a physician or other licensed health
care professional, as appropriate. OSHA has included in paragraph (j)
Definitions, a description of the licensed health care professional. Such
an individual is a physician or other health care professional who holds a
license enabling her or him to independently provide or be delegated the
responsibilities to provide some or all of the health care services required
by this paragraph. In several states, nurse practitioners may be licensed to
independently perform or supervise the evaluations and procedures required by
this paragraph. In such cases, the requirements of this standard can be
accomplished by those practitioners. In addition, where registered nurses are
licensed to perform or supervise some of the requirements of this standard,
those requirements can be accomplished by those professionals. Paragraph
(g)(1)(iii)(D) requires that medical surveillance procedures be provided
according to recommendations of the CDC, current at the time these procedures
are performed, except as specified by this paragraph (g). In other words,
employers must comply with paragraph (g), and with the most current CDC
recommendations in providing medical surveillance. OSHA has set forth what an
employer must do to prevent or minimize occupational exposure in the
employer's workplace. However, CDC, an agency of the U.S. Public Health
Service (USPHS), follows the epidemiology of M. tuberculosis and
periodically revises and updates its guidelines and recommendations to
reflect changes in the diagnosis and treatment of TB. OSHA believes that in
addition to meeting the requirements of paragraph (g), it is appropriate to
follow CDC recommendations, which address screening, medical evaluations, TB
skin test procedures and follow-up (e.g., the administration and
interpretation of skin tests). OSHA
recognizes the dynamic nature of medical knowledge relating to tuberculosis
and notes that CDC recommendations current at the time of the standard's
publication may differ from recommendations at some future time when an
employee evaluation takes place. Knowledge about tuberculosis is expanding. For
example, the medical response to HIV/AIDS as related to tuberculosis
continues to evolve. These are the reasons why OSHA has not simply required
the employer to comply with a particular CDC guideline. OSHA believes that
incorporating the CDC recommendations into the standard by reference enhances
the quality of medical surveillance. This assures that employees are provided
the most current and effective evaluation and treatment. Furthermore, the CDC
recommendations provide consistency with regularly updated medical science
and health care practice. A similar provision was included in the Bloodborne
Pathogens standard 29 CFR 1910.1030 and met with widespread acceptance from
the regulated community. The CDC recommendations cover the specific details
of the medical protocols. Paragraph
(g)(1)(iv) requires that all laboratory tests be performed by an accredited
laboratory. Accreditation by a national accrediting body or its state
equivalent means that the laboratory has participated in a recognized quality
assurance program. (For an explanation of "accredited laboratory"
see paragraph (j) Definitions below). This accreditation process is
required to assure a measure of quality control so that employees receive
accurate information concerning their laboratory tests. The accreditation
requirement assures long-term stability and consistency among laboratory test
procedures and interpretations of results. OSHA recognizes the need for this
requirement and has included it in other standards (e.g., Benzene, 29
CFR 1910.1028; Bloodborne Pathogens, 29 CFR 1910.1030). (2)
Explanation of Terms This
paragraph explains the terms used in paragraph (g) Medical Surveillance.
Paragraphs (g)(2)(i) to (g)(2)(vii) include explanations of the "medical
history", the "physical examination (with emphasis on the pulmonary
system, signs and symptoms of infectious tuberculosis, and factors affecting
immunocompetence)", "TB skin testing", the "face-to-face
determination of ability to wear a respirator and need to be re-fit
tested", "medical management and follow-up", "other
related procedures or tests determined to be necessary", and
"Medical Removal Protection". The applications section, paragraph
(g)(3), describes what must be provided and at what time. Paragraph
(g)(2)(i) describes a medical history, during which the examiner questions
the employee in order to gather information on the employee's pulmonary
system, TB exposure, vaccination, testing and disease status and factors
affecting immunocompetence. A medical history questionnaire may be used as a
starting point for this discussion. OSHA believes that a medical history is
essential for interpreting the TB skin test results, which are also required
by this paragraph (g). The CDC Core Curriculum states: TB
skin testing is a useful tool, but is not perfect. Several factors can affect
the skin test reaction: for example, infection with mycobacteria other than M.
tuberculosis and vaccination with BCG. These factors can lead to
false-positive reactions * * * Other factors, such as anergy, can lead to
false-negative reactions. (Ex. 7-93). Therefore,
the medical history is used to assist in interpreting the TB skin test
results. The medical history also provides information regarding the
employee's potential for increased risk if exposed to tuberculosis. Based on
this information, discussions between the employee and the examiner regarding
the employee's increased risk can assist the employee in decision-making. Paragraph
(g)(2)(ii) describes the physical examination. The physical examination is to
emphasize the pulmonary system, signs and symptoms of active TB disease, and
factors affecting immunocompetence. Such an examination assists the examiner
in detecting evidence of active disease (e.g., rales), differentiating
TB disease from other causes of cough or other signs/symptoms associated with
TB disease, and ascertaining whether signs are present that are compatible
with an immunocompromising health condition. The physical examination is also
required when an employee has signs or symptoms of TB or after a TB skin test
conversion and at other times, if indicated. That
the pulmonary system is emphasized in both the medical history and physical
examination assures that the employee is evaluated with specific attention to
the most common site of infectious TB. Although extrapulmonary tuberculosis
can occur (e.g., in bone, meninges of the brain, and draining
abscesses), it is not usually a source of infection for others. The language
"with emphasis on the pulmonary system" is used to indicate that
while the history and physical examinations evaluate the health of the
patient as a whole, particular emphasis should be placed on the pulmonary
system. Paragraph
(g)(2)(iii) explains the required TB skin testing. TB skin testing is the
cornerstone for early detection of TB transmission among exposed workers. The
American Thoracic Society notes that: Although
currently available TB skin tests are substantially less than 100 % sensitive
and specific for detection of infection with M. tuberculosis, no
better diagnostic methods have yet been devised. (Ex. 5-4) The
TB skin test is an important tool that is useful in identifying employees who
may be eligible for appropriate, early treatment; initiating contact
investigations; and evaluating the effectiveness of the facility's control
program. The requirement for TB skin testing is supported by AHA (Exs. 7-61,
7-29 ), APIC (Ex. 7-30), AIHA (Ex. 7-170) and the CDC 1994 Core Curriculum
which states, "TB screening should be done in groups for which rates of
TB are substantially higher than the general population." [Ex. 7-93]. In
this document, CDC specifically mentions screening for <<health care workers>>, staff of long term care
facilities, correctional facilities, hospices, drug treatment centers, and
nursing homes. Paragraph
(g)(2)(iii) describes the requirement for TB skin testing. TB skin testing,
which only applies to employees whose TB skin test status is not known to be
positive, includes anergy testing if indicated, and consists of an initial
2-step protocol for each employee who has not been previously skin tested
and/or for whom a negative test in the past 12 months cannot be documented. If
the employer has documentation that the employee has had a negative TB skin
test within the past 12 months, that test may be used to fulfill the skin
testing portion of the initial medical surveillance requirements. For
example, if an employer has a new or existing employee for whom: (1) a TB
skin test has not previously been performed, or (2) a negative skin test
result within the past 12 months that cannot be documented, the employer is
required to provide an initial two-step skin test for the employee. Conversely,
if the employer can document a negative skin test result from a test
performed on the employee within the past 12 months, that test can be used to
fulfill the initial skin testing requirement of this section. Subsequent
periodic retesting of the employee is to be performed in accordance with
paragraph (g)(3), as discussed below. It
is important for the employer to determine the current TB skin test status of
employees prior to their initial assignment to a job with occupational
exposure. This "baseline" status can then be used to evaluate
changes in the employees' TB skin test. In
their 1992 guidelines, the American Thoracic Society recommended the
following: Individuals
at high risk for TB should have a TB skin test at least once to assess their
need for preventive therapy and to alert the health care providers of those
with positive skin tests of this medical problem. In institutional settings,
baseline information on the TB skin test status of staff and residents is a
means of identifying candidates for preventive therapy as well as determining
whether transmission of TB is occurring in the facility. For this reason, TB
skin testing upon employment or upon entry should be mandatory for staff and
residents * * * (Ex. 5-80) Previous
BCG vaccination is not a contraindication for skin testing. In its 1994
guidelines, the CDC states: During
the pre-employment physical or when applying for hospital privileges, HCWs
who have the potential for exposure to M. tuberculosis [sic],
including those with a history of BCG vaccination, should have baseline PPD
skin testing performed * * * BCG
vaccination may produce a PPD reaction that cannot be distinguished reliably
from a reaction caused by infection with M. tuberculosis. For a person
who was vaccinated with BCG, the probability that a PPD test reaction results
from infection with M. tuberculosis increases (a) as the size of the
reaction increases, (b) when the person is a contact of a person with TB, (c)
when the person's country of origin has a high prevalence of TB, and (d) as
the length of time between vaccination and PPD testing increases. For
example, a PPD test reaction of >10 mm probably can be attributed
to M. tuberculosis in an adult who was vaccinated with BCG as a child
and who is from a country with a high prevalence of TB. (Ex. 4B) CDC
does not state that BCG vaccination negates the need for baseline and
periodic skin testing but does state that skin tests on vaccinated
individuals need to be interpreted carefully. OSHA's proposed rule is
consistent with the CDC Guidelines on this point. PPD testing is thus not
contraindicated for BCG vaccinated employees; however, such prior vaccination
does mean that other factors, such as the age of the employee and the extent
of induration, must be considered in interpreting the results. The
purpose of performing a two-step test is to correctly identify the
baseline TB skin test status of those employees who are infected with TB but
whose sensitivity to the tuberculin testing material may have waned over the
years. This procedure enhances the proper interpretation of subsequent
positive TB skin test results and is based upon current CDC and American
Thoracic Society recommendations (Exs. 5-80, 6-15, 7-52, 7-93, 7-169). Two-step testing requires an employee to be tested initially and, if the test results
are negative, to be tested again within 1-3 weeks. This second test
stimulates or "boosts" the body's response to the testing material
and results in a more valid reaction. For example, an employee who has not
been recently tested but who is infected with TB from an earlier exposure may
fail to respond to this current test because his or her immune response has
waned over time. However, a second test of this employee will produce a
positive TB skin test that more accurately reflects his or her true TB skin
test status. Thus, the initial use of a two-step testing procedure ensures
that the baseline TB skin test is an accurate reflection of the employee's TB
status and will reduce the likelihood of misinterpreting a
"boosted" reaction on subsequent tests as a conversion. Two-step
testing is also appropriate for individuals who have been BCG vaccinated,
since these individuals can exhibit a boosted reaction. Therefore, two-step
testing of BCG vaccinated individuals can be used to determine their baseline
status, although the skin test results must be interpreted in light of their
previous BCG vaccination. The
two-step testing procedure does not identify those persons who are truly
anergic and, therefore, are not capable of mounting a typical immune response
to the test material. Evaluation of adequate immune response, when determined
to be necessary by the physician or other licensed health care professional,
as appropriate, is determined through anergy testing, and this is provided
for in the explanation of TB skin testing in paragraph (g)(2)(iii). The
CDC recommendations are the guiding documents for TB skin test protocols. By
referring the employer to these recommendations in Paragraph (g)(1)(iii)(D),
OSHA allows for future changes in protocols and procedures that result from
continuing research. Consistent with the CDC guidelines (Exs. 3-33, 3-35,
3-32, 6-15), the American Thoracic Society recommends: The
Mantoux test with 5 Tuberculin Units (TU) of PPD may be used as a diagnostic
aid to detect tuberculous infection and to determine the prevalence of
infection in groups of people. (Ex. 5-4) Proper
administration of a TB skin test results in a reaction described as a classic
example of a delayed (cellular) hypersensitivity reaction. This reaction indicates
infection with mycobacterium, most commonly M. tuberculosis. The
reaction characteristically begins in 5-6 hours, is maximal at 48-72 hours,
and subsides over a period of days (Ex. 5-4). Proper
administration and interpretation of the test is critical and can be complex.
In 1990, the American Thoracic Society revised the criteria for interpreting
the TB skin test (Ex. 5-4). Information such as the health status of the
tested employee, history of BCG vaccination, recent close contact with
persons with active TB, chest x-ray results, and other factors must be
considered when interpreting the TB skin test results. CDC has established
criteria for a TB skin test conversion; that is, when an employee's TB
skin test results change from negative to positive, indicating a recent TB
infection (Ex. 4-B). Because
of the complexity in properly administering and interpreting TB skin tests,
it is essential that only trained individuals perform this function. For this
reason, TB skin testing is to be administered and interpreted by or under the
supervision of a physician or other licensed health care professional as
appropriate and according to CDC recommendations. This language allows
employers to chose from a variety of health care professionals who can
administer and interpret TB skin tests. OSHA is aware that in some worksites,
employees have been allowed to read and interpret their own skin test
results. A surveillance system that allows self-reading and interpretation of
TB skin tests can be problematic. With regard to interpretation of TB skin
test results, the American Thoracic Society states: Intelligent
interpretation of skin test results requires a knowledge of the antigen used
(tuberculin), the immunologic basis for the reaction to the antigen, the
technique(s) of administering and reading the test, and the results of
epidemiologic and clinical experience with the test. (Ex. 5-4) In
its 1994 Core Curriculum on Tuberculosis (Ex. 7-93), CDC describes the
complexities of interpreting the induration resulting from TB skin testing. A
number of factors can affect the size of a TB skin test induration relative
to whether or not the test should be interpreted as being positive. For
example, induration of 5 mm or more is classified as positive for persons
with known or suspected HIV infection, while an induration must be 10 mm to
be classified as positive in persons who are foreign-born in high prevalence
countries. An induration of 15 mm or more is classified as positive in
certain other situations. In addition, TB skin testing can result in both
false positive and false negative results. Clearly,
interpreting TB skin test results requires professional expertise and must be
performed by or under the supervision of a physician or other licensed health
care professional, as appropriate, by an individual with training and
experience in performing the test and interpreting the result. Proper use of
the TB skin test as a medical surveillance tool will require two visits to
the health care professional: one to receive the test and one to
read/interpret the test results. However, considering the critical importance
of this element, OSHA believes that allowing employees to read and interpret
their own tests or allowing their peers to do so (unless they meet the
criteria discussed above) compromises the quality and accuracy of the testing
procedure. Paragraph
(g)(2)(v) explains that medical management and follow-up include diagnosis,
and, where appropriate, prophylaxis and treatment related to TB infection and
disease. The employer must provide medical management and follow-up for
occupationally exposed employees with skin test conversions [paragraph
(g)(3)(i)(D)], or those who undergo an exposure incident whether or not they
are categorized as occupationally exposed [paragraphs (g)(1)(ii) and
(g)(3)(i)(C)]. In addition, any time an occupationally exposed employee
develops signs and symptoms of infectious tuberculosis, medical management
and follow-up are required [paragraph (g)(3)(i)(B)]. John E. McGowan
addressed follow-up in the 1995 article entitled "Nosocomial
Tuberculosis: New Progress in Control and Prevention," published in
Clinical Infectious Diseases. He states, If
the PPD skin testing program for <<health care workers>> is to be useful, several steps
are crucial. * * * The institution also must make sure that the occupational
health service undertakes careful follow-up of workers found to have positive
TB skin tests or tuberculosis disease. This follow-up should include
counseling, careful monitoring of therapy (when prescribed) until its
completion and evaluation of fitness to return to work. (Ex. 7-248). Paragraph
(g)(2)(vi) explains that other related tests and procedures are any
TB-related tests and procedures determined to be necessary by the physician
or other licensed health care professional, as appropriate. These procedures
or tests could include chest radiographs, sputum smears, or other testing
determined to be necessary to make an assessment, a diagnosis, or medically
manage the employee. An example of a program that integrates testing and
examinations was given at the 1994 meeting of the Society for Occupational
and Environmental Health, by Carol Murdzak who presented the University of
Manitoba's Medical Surveillance program. Her presentation, entitled
"Conducting a Medical Surveillance Program to Prevent and Control
Transmission of TB in a Health Care Institution" demonstrates the use of
skin testing and general review of health status for employee surveillance. Results
of TB skin testing and the review of health status determine the need for
chest x-ray and further medical evaluation in this program (Ex.7-169). (3)
Application Medical
examinations in the form of medical histories, physical examinations, TB skin
testing and other related tests and procedures are necessary in order to
promptly identify and treat employees with infectious tuberculosis. Paragraph
(g)(3), Application, specifies what an employer must provide. In each
situation set forth in paragraph (g)(3), the employer must provide medical
examinations, tests and procedures as specified. Some of the provisions are
offered only "if indicated," which means that the physician or
other licensed health care professional, as appropriate, has determined that
further tests or procedures are needed. For example, an employee who has no
history of illness or being immunocompromised and whose TB skin test is
negative at the time of initial assignment is not required to be offered a
physical examination unless the examiner determines that a physical
examination is indicated. However, if at the time of annual skin test, the
employee has a skin test conversion, a physical examination is required. Paragraph
(g)(3)(i)(A) requires that, before the time an employee is initially assigned
to a job with occupational exposure (or within 60 days from the effective
date of the standard for employees already assigned to jobs with occupational
exposure), the employee be provided with a medical history, TB skin testing,
and, if indicated, a physical examination and other related tests and
procedures. OSHA
requires the initial medical history to assist in assessing the employee's
health. This information will provide a baseline health status that can be
used to evaluate (1) whether the employee has a pre-existing condition that
may be exacerbated by occupational exposure to TB and (2) any future health
conditions that may arise that are relevant to occupational exposure to TB. OSHA
does not believe that an initial physical examination for all occupationally
exposed employees is necessarily warranted. However, the Agency does believe
that a physical examination, if determined to be indicated by the examiner
based on the medical history and TB skin test results, is useful and
effective. The
note to paragraph (g)(3)(i)(A) specifies that if an employee has had a
medical examination within the twelve (12) months preceding the effective
date of the standard and the employer has documentation of that examination,
only the medical surveillance provisions required by the standard that were
not included in the examination need to be provided. The Agency realizes that
employees may have received at least some of the elements of the required
medical surveillance provisions shortly before the effective date of the
standard. In these situations, a full TB examination would not need to be
repeated. In
addition, the proposed standard allows the baseline TB skin testing status of
an employee to be established by documentation of a TB skin test that was
administered within the previous 12 months. For example, if an employee has a
written record of a TB skin test within the last 12 months, that information
can be used to document the employee's baseline TB skin test status and
another TB skin test at the time of the initial medical examination is not
necessary. When utilizing results from a previous medical examination and
skin test to fulfill the initial medical surveillance requirements, the
employer must use the date(s) of the previous medical exam and skin test to
determine the date(s) of the employee's next medical examination and skin
test. In no case shall the interval between the previous examination and skin
test and the next examination and skin test exceed 12 months. These
provisions are designed to avoid unnecessary testing of employees and do not
compromise the quality of the medical surveillance. Information
(e.g., medical history) obtained from a medical examination in the
past 12 months is unlikely to change within this span of time. However, this
may not be the case with regard to previous skin testing results. While OSHA
is proposing to accept a skin test performed within the past 12 months as a
substitute for performing an initial baseline skin test, an employer
utilizing a new employee's negative skin testing result obtained more than 3
months prior to beginning the new job may be uncertain as to the source and
time of infection if the employee tests positive at his or her next skin
test. More specifically, conversion normally occurs within 3 months of
infection. Therefore, an employee would have been negative at his or her last
skin test, e.g., 7 months previously, and have been infected just
after the skin test and subsequently converted. In such a case, an employer
may rely on the previous negative skin test as the baseline does not need to
test the new employee until 5 months later (i.e., annual skin test
frequency), at which time the employee would test positive and be identified
as a converter. In this situation, the new employer would not be able to
determine if the employee's conversion had occurred as a result of exposure
occurring previous to hire or from exposure in his or her current work
setting. Regardless of the source of the conversions, the employer would be
required by the standard to initiate medical management and a follow-up
investigation, which might also entail skin testing other employees in the
worksite to determine if other conversions had taken place, a step that would
not be necessary if the employee had been correctly identified as positive
upon entry into the workplace. In view of this, employers may choose to
perform an initial baseline skin test on each new employee before the
employee enters the work setting. Once
an employee is on the job, paragraph (g)(3)(i)(A) requires employers to
periodically retest employees who have negative TB skin tests in order to
identify those employees whose skin test status changes, indicating that they
have been infected. Because the baseline TB skin test provides only a
"snapshot" of the TB skin test status of the employee and because
exposure and subsequent infection can occur at any time, periodic testing is
necessary. The American Thoracic Society recommends: *
* * follow-up skin-testing should be conducted on at least an annual basis
among the staffs of TB clinics, health care facilities caring for patients
with HIV infection, mycobacteriology laboratories, shelters for the homeless,
nursing homes, substance-abuse treatment centers, dialysis units, and
correctional institutions. (Ex. 5-80) When
TB exposure results in infection, early identification allows employees to
have options regarding prophylactic treatment, thereby reducing the
likelihood that the infection will progress to disease. OSHA
recognizes the importance of periodic testing to monitor the status of
employee's skin test results. In their 1994 Guidelines for Preventing the
Transmission of Tuberculosis in Health-Care Facilities, the CDC recommends
that the frequency of PPD skin testing of employees be based upon the
individual facility's risk assessment in conjunction with the criteria put
forth by the CDC (Ex. 4B). For situations that meet certain CDC criteria, CDC
recommends that employees receive a repeat TB skin test every 3 months, six
months or annually, depending upon the risk assessment. OSHA's
proposed standard does not require a risk assessment of the type described by
CDC and would extend coverage to worksites other than "health-care
facilities" as described in the CDC document (Ex. 4B). Consequently,
OSHA is proposing that repeat TB skin test be performed every 6 months or
annually, depending upon the exposure determination. This testing frequency
is expected to be both practical and effective in early identification of
skin test conversions in the various worksites described in the Scope. The
requirements for more frequent TB skin tests (e.g., 3 months after an
exposure incident, or if deemed necessary by a licensed health care
professional) ensures that employees' health is not compromised. An
exemption to this annual testing is permitted for an employer who can
demonstrate that his or her facility or work setting: (1) Does not admit or
provide medical services to individuals with suspected or confirmed
infectious TB, (2) has had no cases of confirmed infectious TB in the past 12
months, and (3) is located in a county that, in the past two years, has had 0
cases of confirmed infectious TB reported in one year and fewer than 6 cases
of confirmed infectious TB reported in the other year. In these settings only
a baseline TB skin test is required. This is discussed earlier under
paragraph b, application. Paragraph
(g)(3)(i)(B) requires that, when an employee has signs or symptoms of TB,
either observed or self-reported, the employee be provided a medical history,
physical examination, TB skin testing, medical management and follow-up, and
other related tests and procedures determined to be necessary. CDC states
that the presence of signs or symptoms of tuberculosis in the employee
requires prompt medical evaluation (Ex. 7-52, 7-93), and such evaluation
provides an opportunity for initiating drug therapy. Furthermore, identifying
those with infectious pulmonary TB disease enables the employer to remove
them from the workplace, preventing exposure of other employees. Paragraph
(g)(3)(i)(C) requires that when an employee incurs an exposure incident, a
medical history, TB skin testing, medical management and follow-up, and, if
indicated, a physical examination and other related tests and procedures be
provided. Evaluation and follow-up after each exposure incident help detect
any resultant infections, as well as prevent infection in other employees,
benefitting the health of all employees. Following
exposure, infected workers will usually develop a positive response to a TB
skin test (Exs. 7-50, 7-93, 5-4). In certain cases, workers may also display
signs or symptoms compatible with tuberculosis disease such as complaints of
persistent cough (over 3 weeks in duration), bloody sputum, night sweats,
weight loss, loss of appetite or fever. Use of the TB skin test has been
recognized as a tool in the early identification of infection and for disease
surveillance and follow-up. In paragraph (g)(3)(i)(C), the proposed standard
also requires employers to provide testing for employees as soon as feasible
after an exposure incident, unless a negative TB skin test has been
documented within the preceding 3 months. If this baseline skin test is
negative, another TB skin test shall be repeated 3 months after the exposure
incident. In
order to accurately determine if an exposure incident has resulted in
infection, the employer must first know the baseline skin test status of the
affected employee(s) at the time of the exposure incident. Typically, skin
test conversion can be documented approximately 2-10 weeks following
infection (Ex. 7-52). Consequently, it can be reasonably assumed that a
negative TB skin test within the three months prior to the incident is
sufficiently indicative of the employee's status at the time of the exposure
incident. For
those employees who do not have a documented negative skin test within the
past three months, the employer must determine their TB skin test status as
soon as feasible after the exposure incident. The requirement of "as
soon as feasible" in the provision puts the employer under the
obligation of performing the TB skin test quickly, i.e., before infection
resulting from the exposure would be manifested as a conversion. This assures
that a true indication of the employee's skin test status at the time of the
incident is obtained. The
purpose of the initial TB skin test following an exposure incident is to
establish the TB skin test status of the employee(s) at the time of the
incident. From this baseline, changes in TB skin test status can be
identified. This initial test would not detect infection resulting from the
exposure, since there would not have been sufficient time for conversion to
occur. Hence, the employer is required to provide a repeat TB skin test three
months after the exposure incident to determine if infection has occurred. This
requirement reflects current CDC recommendations (Ex. 4B). Paragraph
(g)(3)(i)(D) requires that when an employee has a TB skin test conversion,
the employee receive a medical history, a physical examination, medical
management and follow-up, and other tests and procedures determined to be
necessary. This provision assures that employees with skin test conversions
receive appropriate evaluation for preventive therapy and for infectious
tuberculosis. OSHA included the provision for early identification of disease
since, as the CDC has stated in their guidelines, infectious tuberculosis
disease can be prevented by the early treatment of tuberculosis infection. In
paragraph (g)(3)(i)(E), the proposed standard requires employers to provide
TB skin testing within 30 days prior to termination of employment. The
rationale for this requirement is two-fold. First, this requirement permits
employees whose employment is terminated after an unrecognized exposure
incident, but before their next regularly scheduled TB skin test, to
determine their current (exit) TB skin test status. OSHA recognizes that in
some instances employees may be in the process of converting from negative to
positive TB skin test results at the time of the exit testing and that some
of these cases will be missed. Also missed will be employees who decline
testing or who vacate their position immediately or without notice. While
such situations are possible, the Agency believes that these occurrences
would be rare. Secondly, by detecting recent conversions, appropriate steps
can be taken by the employer to investigate the cause of the exposure. This
helps prevent future exposures in those areas or situations where the exiting
employee's infection may have occurred. Paragraph
(g)(3)(i)(F) requires that a medical history, physical examination, TB skin
testing, determinations of the employee's ability to wear a respirator,
medical management and follow-up or other related tests and procedures be
conducted at any other time determined necessary by the physician or other
licensed health care professional, as appropriate. This allows the physician
or other licensed health care professional, as appropriate, to recognize the
individual differences in employees' medical status and response to TB
infection and increase the frequency or content of examination as needed. Some
workers who have certain health conditions may need more frequent evaluation
(Ex. 4B). For example, individuals who have a condition that may interfere
with an accurate interpretation of TB skin test results (e.g., the
development of test anergy in an employee who is on chemotherapy for cancer
treatment), may warrant more frequent evaluations because of the high risk
for rapid progression to TB disease if he or she becomes infected. (Ex. 4B) Paragraph
(g)(3)(ii) sets forth provisions regarding employees who wear respirators. Paragraph
(g)(3)(ii)(A) requires that a face-to-face determination of the employee's
ability to wear the respirator be accomplished before initial assignment to a
job with occupational exposure (or within 60 days of the effective date of
the standard) and at least annually thereafter. As discussed above under
explanation of terms, this is a verbal exchange to assess health factors that
could affect the employee's ability to wear a respirator. An initial
determination is made before assignment to a job requiring respirator use to
assure that the employee's health factors have been properly evaluated prior
to incurring exposure to M. tuberculosis. This determination must also
be made annually to assure that no health conditions have arisen that might
limit an employee's ability to wear a respirator. Such
conditions may arise and be noted prior to the annual determination. For
example, the employee may experience unusual difficulty while being fitted or
while using the respirator. In these situations, it is not appropriate to
wait until the annual determination. Therefore, paragraph (g)(3)(ii)(B)
requires that a face-to-face determination of the employee's ability to wear
a respirator, including relevant components of a medical history and, if
indicated, a physical examination and other related tests and procedures, be
provided whenever the employee experiences unusual difficulty while being
fitted or while using a respirator. Paragraph
(g)(3)(iii) requires employers to provide TB skin tests every 6 months for
each employee who enters AFB isolation rooms or areas, performs or is present
during the performance of high-hazard procedures, transports or is present
during the transport of an individual with suspected or confirmed infectious
TB in enclosed vehicles, or works in intake areas where early identification
is performed in facilities where 6 or more individuals with confirmed
infectious TB have been encountered within the past 12 months. OSHA believes
that employees who perform these activities are exposed more intensely and
frequently to individuals with suspected or confirmed infectious tuberculosis
and should, therefore, be tested more frequently. (4)
Additional Requirements Paragraph
(g)(4) (i) through (iv) contain the additional requirements an employer must
meet. Paragraph (g)(4)(i) requires that the physician or other licensed
health care professional, as appropriate, verbally notifies the employer and
the employee as soon as feasible if an employee is determined to have
suspected or confirmed infectious tuberculosis. In this way an infectious
employee can be removed from the workplace, thereby minimizing occupational
exposure for other workers. Paragraph (g)(7)(i), Written Opinion, allows 15
days before the employer must provide the employee with the written opinion
of medical evaluations from the physician or other licensed health care
professional, as appropriate. In situations where an employee is determined
to be potentially infectious, this time period leads to unnecessary delays in
removal from the workplace and disease treatment. Therefore, OSHA requires
the verbal notification to expedite treatment and prevent spread of disease
to other employees. The
proposed standard, in paragraph (g)(4)(ii), requires the employer to notify
each employee who has had an exposure incident when the employer identifies
an individual with confirmed infectious TB who was previously unidentified. For
example, if a newly admitted patient undergoes diagnostic and therapeutic
evaluation for suspected pulmonary malignancy, and the diagnosis of
infectious tuberculosis is not made until several days after hospitalization,
all hospital staff who have had exposure must be identified and provided TB
skin test and follow-up. OSHA intends to assure that employees are provided
with opportunities for early detection of tuberculosis infection. These
provisions are consistent with the general purpose of tuberculosis medical
surveillance as recommended by the CDC, and they are included to assist all
employees in receiving the full benefits provided by the standard. Determination
of the drug susceptibility of the M. tuberculosis isolate from the
source of an exposure incident resulting in a TB skin test conversion is
required by paragraph (g)(4)(iii) unless the employer can establish that such
a determination is infeasible. Information regarding drug susceptibility
assists the examiner in deciding the most effective treatment therapy for the
exposed employee, particularly if the source is a drug resistant strain of M.
tuberculosis. Drug susceptibility testing of the source isolate is
recommended by CDC (Ex. 4B). OSHA includes the provision regarding
infeasibility because certain TB skin test conversions may involve unknown
exposure sources. This can make identification of the isolate and therefore
drug susceptibility testing infeasible or even impossible. It is the
responsibility of the employer to establish that this is infeasible, if such
is the case. Employers must make a good faith effort to identify M.
tuberculosis isolates and obtain the drug susceptibility testing. Paragraph
(g)(4)(iv) requires the employer to investigate and document the
circumstances surrounding an exposure incident or TB skin test conversion and
to determine if changes can be instituted that will prevent similar
occurrences in the future. The
provision assures that employers obtain feedback regarding the circumstances
of employee exposures and use the information to eliminate or decrease
specific circumstances leading to exposure. For example, exposure incident
investigation shows that an employee was exposed to tuberculosis as a result
of recirculation of air containing infectious droplet nuclei. Further
investigation shows inadequate local or general ventilation in the workplace.
The employer can now repair the ventilation system and prevent future
exposure incidents. Another example of corrective measures may be including a
stronger training emphasis on certain procedures where proper work practices
might have decreased the likelihood of transmission of tuberculosis. Employers
can obtain further guidance regarding investigations for TB skin test
conversions and exposure incidents in <<health care workers by reading the 1994 CDC
guidelines. (5)
Medical Removal Protection Paragraph
(g)(5)(i) requires that employees with suspected or confirmed infectious
tuberculosis be removed from the workplace until determined to be
non-infectious according to current CDC recommendations. Infectious TB is
contagious and removal is essential for the protection of other workers. An
employee's "infectiousness" is determined by the physician or other
licensed health care professional, as appropriate, who informs the employer
as required in paragraphs (g)(4)(i) and (g)(7) of this section. Paragraph
(g)(5)(ii) states that for employees removed from the workplace under
paragraph (g)(5)(i), the employer shall maintain the total normal earnings,
seniority, and all other employee rights and benefits, including the right to
former job status, as if the employee had not been removed from the job or
otherwise been medically limited until the employee is determined to be
noninfectious or for a maximum of 18 months, whichever comes first. Paragraph
(g)(5)(iii) provides medical removal protection for employees removed from
the workplace under paragraph (f)(4)(viii) of Respiratory Protection. The
provision requires the employer to transfer the employee to comparable work
for which the employee is qualified or can be trained in a short period (up
to 6 months), where the use of respiratory protection is not required. OSHA
requires that if no such work is available, the employer shall maintain the
employee's total normal earnings, seniority, and all other employee rights
and benefits until such work becomes available or for 18 months, whichever
comes first. The
requirement referring to the employee's right to return to his or her former
job is not intended to expand upon or restrict any rights an employee has or
would have had, to a specific job classification or position under the terms
of a collective bargaining agreement. Where the employer removes an employee
from exposure to tuberculosis, the employee is entitled to full medical
removal protection benefits as provided for under the standard. The
medical removal requirement is an indispensable part of this standard. The
medical removal protection helps assure that affected employees participate
in medical surveillance and seek appropriate care. If employees fear losing
their jobs as a result of their medical condition they may attempt to hide
the illness, thereby infecting many more workers and other people and
jeopardizing their own health. The requirement for medical removal assures
that an infectious employee will not be terminated, laid off, or transferred
to another job (possibly at a lower pay grade) upon returning to work. Consequently,
this protection should reduce reluctance on the part of the employee to
participate in medical surveillance. The employee's health will be protected
and the health of co-workers and others who come into contact with that
employee will be protected, also. OSHA
believes that the cost of protecting worker health to the extent feasible is
an appropriate cost of doing business since employers are obligated by the
OSH Act to provide safe and healthful places of employment. Consequently, the
costs of medical removal, like the costs of respirators and engineering
controls, are borne by employers rather than individual workers. If
a removed employee files a claim for workers' compensation payments for a
tuberculosis-related disability, then the employer must continue to provide
medical removal protection benefits pending disposition of the claim. To the
extent that an award is made to the employee for earnings lost during the
period of removal, the employer's medical removal protection obligation may
be reduced by such amount. The employer's obligation to provide medical
removal protection benefits to a removed employee may be reduced to the
extent that the employee receives compensation for earnings lost during the
period of removal either from a publicly or employer-funded compensation
program, or receives income from employment with another employer which was
made possible by virtue of the employee's removal. Medical
removal should not be viewed as an alternative to primary control
(prevention) of workers' exposure to tuberculosis; rather, it should be used
as a secondary means of protection, where other methods of control have
failed to protect. The stipulation of an 18 month time period of protection
is consistent with other OSHA standards (e.g., Cadmium, 29 CFR
1910.1027; Lead in Construction, 29 CFR 1926.62). The provision of medical
removal and the costs associated with the program may indirectly provide
employers with economic incentives to comply with other provisions of the
standard. It can be expected that the costs of medical removal will decrease
as employer compliance with other provisions of the standard increases. (6)
Information Provided to Physician or Other Licensed Health Care Professionals Paragraph
(g)(6)(i) requires the employer to assure that the health care professionals
responsible for the medical surveillance receive a copy of this regulation. OSHA
believes it is the employer's responsibility to inform the health care
professionals responsible for medical surveillance of the requirements of
this standard. This will help assure that these individuals are aware of and
implement the requirements. This provision is included in other OSHA
standards (e.g., Benzene, 29 CFR 1910.1028; Bloodborne Pathogens, 29
CFR 1910.1030). Paragraph
(g)(6)(ii) requires the employer to assure that the physician or other
licensed health care professional, as appropriate, evaluating an employee
after an exposure incident receives: (A) A description of the exposed
employee's duties as they related to the exposure incident; (B) a description
of the circumstances under which the exposure incident occurred; (C) the
employee's diagnostic test results, including drug susceptibility pattern, or
other information relating to the source of exposure that could assist in the
medical management of the employee; and (D) all of the employee's medical
records relevant to the medical evaluation of the employee, including TB skin
test results. Since the individual responsible for medical surveillance may
not necessarily be the person evaluating an employee after an exposure
incident, it is necessary to also provide a copy of this standard to the
evaluating physician or other appropriate licensed health care professional,
as required by paragraph (g)(6)(i). In this way, the evaluator will also be
informed of and implement the standard's requirements. All of the above
information is essential to follow-up evaluation, and helps assure that an
accurate determination can be made regarding appropriate medical treatment of
the exposed employee. This provision is consistent with other OSHA standards
(e.g., Bloodborne Pathogens, 29 CFR 1910.1030, Benzene, 29 CFR
1910.1028). (7)
Written Opinion Paragraph
(g)(7)(i) states that the employer shall obtain and provide the employee with
a copy of the written opinion of the physician or other licensed health care
professional, as appropriate, within 15 days of the completion of all medical
evaluations required by this section. The purpose of requiring the employer
to obtain a written opinion is to assure that the employer is provided with
documentation that the medical evaluation of the employee (1) has taken place
and that the employee has been informed of the results; (2) has included an
evaluation of the employee's need for medical removal or work restriction;
(3) describes the employee's TB skin test status so that the employer can
assess action needed to prevent further exposure; and (4) informs the
employer of the employee's infectivity status so that the employer can take
action to prevent the employee from becoming a source of infection for other
employees. The
employer has a right to know the information contained in the written opinion
and may retain the original written opinion, but must provide a copy to the
employee. The 15 day provision assures that the employee is informed in a
timely manner regarding information received by the employer and is
consistent with other OSHA standards (e.g., Formaldehyde, 29 CFR
1910.1048; Benzene, 29 CFR 1910.1028; Bloodborne Pathogens, 29 CFR
1910.1030). In
addition, the written opinion is required to assure the employer that the
employee has been provided with information about any medical conditions
resulting from exposure to tuberculosis which require further evaluation or
treatment. OSHA
believes it is important that employers know if their employees have had
evaluations for tuberculosis infection or exposure incidents, and that
physicians or other appropriate licensed health care professionals, acting as
agents for the employer, have provided the employer with written
documentation that these evaluations occurred. However, paragraph (g)(7)(ii)
limits the information the employer is provided in order to protect the
privacy of the employee. The requirement for a written opinion after a
medical evaluation has been included in other OSHA standards (e.g.,
Occupational Exposures to Hazardous Chemicals in Laboratories, 29 CFR
1910.1450; Formaldehyde, 29 CFR 1910.1048; Bloodborne Pathogens, 29 CFR
1910.1030). Paragraph
(g)(7)(ii)(E) requires the written opinion to state any recommendations for
medical removal or work restrictions and the employee's ability to wear a
respirator. This recommendation must be in accordance with paragraphs
(g)(5)(i) and (f)(5)(viii) of this section. Including this information in the
written opinion assures that the employer is provided with written
documentation of the need for removal of an employee with infectious
tuberculosis from the workplace. The provision also assures that the employer
is aware of any work restrictions on the employee and the employee's ability
or inability to wear a respirator. This information enables the employer to
take appropriate steps in managing the employee's duties upon return to the
workplace. OSHA recognizes the need for this provision and has included it in
other standards (e.g., Lead in Construction, 29 CFR 1926.62). Paragraph
(g)(7)(iii) states that all other findings or diagnoses shall remain
confidential and shall not be included in the written report. OSHA believes that
all health care professionals have an obligation to view medical information
gathered or learned during tuberculosis medical surveillance or post-exposure
evaluation as confidential medical information. As stated previously, the
maintenance of confidentiality encourages participation in medical
surveillance by allaying employee concern that medical conditions unrelated
to tuberculosis exposure will be communicated to the employer. OSHA also
recognizes that successful medical surveillance and medical management and
follow-up programs must guarantee this confidentiality, the specific
requirements on confidentiality can be found in applicable state and federal
laws and regulations that cover medical privacy and confidentiality. Finally,
OSHA recognizes the need for this provision and has included it in other
standards (e.g., Bloodborne Pathogens, 29 CFR 1910.1030). Paragraph (h) Communication of Hazards and Training Paragraph
(h), Communication of Hazards and Training, addresses the issues of
transmitting information to employees about the hazards of tuberculosis
through the use of labels, signs, and information and training. These
provisions apply to all operations that come under the coverage of paragraph (a),
Scope, of this section. Although OSHA has an existing standard, Hazard
Communication (29 CFR 1910.1200), which requires an employer to inform
employees about the hazards of chemical substances they are exposed to
occupationally, that standard does not apply to biological hazards such as
TB. Consequently, it is OSHA's intent in this paragraph to assure that
employees will receive adequate warning through labels, signs, and training
so that the employee understands the hazard and can take steps to eliminate
or minimize his or her exposure to tuberculosis. Paragraphs
(h)(1) and (h)(2) of the proposed standard for tuberculosis provide the
specific labeling and sign requirements that are to be used to warn employees
of hazards to which they are exposed. The requirements for labels and signs
are consistent with section 6(b)(7) of the OSH Act, which prescribes the use
of labels or other appropriate forms of warning to apprise employees of
occupational hazards. As noted in paragraphs (c)(2)(v), (d)(3), and (d)(5)
above, settings where home health care and home-based hospice care are
provided are not required to have engineering controls and, therefore, the
signs and labeling would not be required in these cases. Labels Paragraph
(h)(1)(i) requires that air systems that may reasonably be anticipated to
contain aerosolized M. tuberculosis must be labeled at all points
where ducts are accessed prior to a HEPA filter and at duct access points,
fans, and discharge outlets of non-HEPA filtered direct discharge systems. The
label must state "Contaminated Air -- Respiratory Protection
Required." The provision for labeling of air ducts that may reasonably
be anticipated to contain aerosolized M. tuberculosis, with the
proposed hazard warning, is supported by the CDC in its discussion of HEPA
filter systems. This discussion states: Appropriate
respiratory protection should be worn while performing maintenance and
testing procedures. In addition, filter housing and ducts leading to the
housing should be labeled clearly with the words "Contaminated Air"
(or a similar warning). (Ex. 4B) The
intent of this provision is to assure that employees who may be accessing
these systems for the purposes of activities such as maintenance, replacement
of filters, and connection of additional ductwork are warned of the presence
of air that may contain aerosolized M. tuberculosis so that
appropriate precautions can be taken. Consequently, labels are to be placed
at all points where these systems are accessed. In
situations where air that may reasonably be anticipated to contain
aerosolized M. tuberculosis is discharged directly to the outside, the
exhaust outlets are also to be labeled. This is especially important since
these outlets will most likely be at a remote location from the contaminated
air source. Employees working in these locations would have no warning of the
hazard if these ducts were not labeled. In addition, a number of exhaust
outlets from a variety of sources may be present in an area (e.g., a
hospital roof). In such situations, labeling also serves to distinguish
contaminated air exhaust outlets from others in the vicinity. The
proposed provision does not require that a symbol (e.g.,
"STOP" sign) be included on the duct labels. OSHA believes that, in
many situations, the label will be stenciled onto the duct, similar to the
labeling used on other piping and duct labels currently being employed in
some of these facilities. In addition, the group of workers accessing ducts
will likely be a well-defined, skilled group that can be trained to recognize
the text's warning. However, OSHA seeks comment on whether a symbol on duct
labels is necessary and any information regarding the current use of such
symbols. Paragraph
(h)(1)(ii) requires that clinical and research laboratory wastes that are
contaminated with M. tuberculosis and are to be decontaminated outside
of the immediate laboratory must be labeled with the biohazard symbol or
placed in a red container(s). This provision is intended to assure that
employees are adequately warned that these containers require special
handling. In addition, the label or color-coding serves as notice that
certain precautions may be necessary should materials in the container be
released (e.g., a spill). This provision closely follows the
recommendations outlined in the CDC-NIH publication "Biosafety in
Microbiological and Biomedical Laboratories" (Ex. 7-72) and is in
accordance with the labeling requirements of paragraph (e)(2)(i)(D), Clinical
and Research Laboratories, of this section. Signs Paragraph
(h)(2) contains the provisions relative to the posting of warning signs in
areas where employees may be exposed to droplet nuclei or other aerosols of M.
tuberculosis. More specifically, paragraph (h)(2)(i)(A) requires that
signs be posted at the entrances to rooms or areas used to isolate an
individual with suspected or confirmed infectious TB. The term "rooms or
areas" is used in order to expand the requirement beyond the AFB
isolation room or area. Throughout the course of a day various employees may
enter such rooms or areas in order to carry out their duties. These employees
can include physicians, nurses, respiratory therapists, housekeepers, and
dietary workers. Posting a sign at the entrance of those rooms or areas where
an individual with suspected or confirmed infectious TB is isolated serves to
warn employees that entry into the room or area requires that certain
precautions be taken. In addition, the employer may have implemented a
program to minimize the number of employees who enter such rooms or areas. In
this case, the sign serves as notice that entry may not be permitted for a
particular employee or group of employees. As an additional public health
benefit, such signs will also provide warning to visitors or family members
who may be entering the area and are unaware of the hazard. Paragraph
(h)(2)(i)(B) requires that signs be posted at the entrances to areas where
procedures or services are being performed on an individual with suspected or
confirmed infectious TB. Although it is critically important to provide
appropriate warning to employees who may inadvertently enter an isolation
room, other areas of the facility are of concern as well. Special treatment
areas, such as bronchoscopy suites, respiratory therapy areas where
cough-inducing procedures are performed, or radiology examination rooms may,
at one time or another, be occupied by an individual with suspected or
confirmed infectious TB. When individuals with suspected or confirmed
tuberculosis are occupying these areas, the area must have signs placed at
the entrances in order to warn employees of the hazard. The
risk of exposure to aerosolized M. tuberculosis also exists in
clinical and research laboratories where specimens, cultures, and stocks
containing the bacilli are present. Therefore, paragraph (h)(2)(i)(C)
requires that a sign be posted at the entrance to laboratories where M.
tuberculosis is present. Posting of such a sign is consistent with the
recommendations of the CDC/NIH publication "Biosafety in Microbiological
and Biomedical Laboratories" (Ex. 7-72) and is in accordance with the
sign posting requirement of paragraph (e)(2)(ii)(E), Clinical and Research
Laboratories, of this section. Even
though a suspected or confirmed infectious individual is no longer present in
a room or area, the droplet nuclei generated by that individual may continue
to drift in the air. Consequently, the air in the room or area presents a
risk of TB infection until the droplet nuclei are removed. With this in mind,
paragraph (h)(2)(ii) requires that when an AFB isolation room or area is
vacated by an individual with suspected or confirmed infectious TB, unless
the individual has been medically determined to be noninfectious, the sign
shall remain posted at the entrance until the room or area has been
ventilated according to CDC recommendations for a removal efficiency of 99.9
%, to prevent entry without the use of respiratory protection [The rationale
for specifying this removal efficiency has been discussed previously under
paragraph (d), Work Practices and Engineering Controls]. This
provision is supported by the CDC's current recommendations for tuberculosis
control (Ex. 4B). The
CDC has published guidelines regarding the length of time for such sanitation
of the room air based upon the air exchanges per hour (see Appendix C of this
section). Requiring that the sign remain posted until the room or area is
adequately ventilated will assure that unprotected employees do not
inadvertently enter while an infection risk is still present. Until
such time as the room or area has been adequately ventilated, employees
entering the area must wear respiratory protection. This paragraph is
designed to address the situations where employees will be entering or using
a room or area previously occupied by an individual with suspected or
confirmed infectious TB before the room or area has been satisfactorily
ventilated. For example, when an infectious tuberculosis patient is
discharged from a facility and the room is needed for an incoming new
patient, certain housekeeping and maintenance functions need to be done between
patient occupancies. Employees who must perform the tasks required to prepare
the room for the next patient must wear respiratory protection until such
time as the room has been adequately ventilated, based upon the CDC criteria.
Obviously, if the room was previously occupied by an individual with
suspected infectious TB and that individual is medically determined to be
noninfectious, it would not be necessary to ventilate the room to remove M.
tuberculosis nor to continue to post a sign at the entrance to the room
since there would be no tuberculosis bacilli present. OSHA
has given much consideration to what sign should be required for posting
outside of isolation rooms or areas and for areas where procedures or
services are performed on individuals with suspected or confirmed infectious
TB. The purpose of the sign is to convey a uniform warning along with the
necessary precautions to be used for the particular situation. The
sign recommended by the CDC in 1983 in their "CDC Guidelines for
Isolation Precautions in Hospitals" (Ex. 7-112) read "AFB
Isolation" and then listed the requirements for entry. However, the
instructions on the CDC sign are different from OSHA's requirements. For
example, the sign instructed workers that "Masks are indicated only when
patient is coughing and does not reliably cover mouth", a recommendation
that is currently outdated and no longer recommended by CDC. The document
contained another sign for "Respiratory Isolation" but this sign
was designed for use with a number of respiratory hazards (rubella,
meningococcal meningitis, chickenpox) that are not addressed in OSHA's
proposed standard. Neither the 1990 CDC tuberculosis guidelines (Ex. 3-32)
nor the 1994 CDC tuberculosis guidelines (Ex. 4B) provided help with this
issue. OSHA also considered using a sign having the words "AFB
Isolation" however, there is some concern that "AFB Isolation"
could compromise patient confidentiality. For example, that sign outside of a
treatment area or isolation room would allow members of the public or
employees with no "need to know" to discern the potential diagnosis
of the individual being isolated. In
addition, OSHA was unable to find uniform recommendations about signs in
sources outside of the CDC. A number of facilities use signs to warn employees
of the hazard of TB, but these signs vary widely and often had been developed
for a particular facility. Thus, facilities that were using TB warning signs
did not appear to be universally applying a specific sign. The
Agency does not believe, however, that development of a sign should be left
to individual employers since this could lead to a variety of signs that may
not provide adequate warning of the hazard. In the work settings covered by
the proposal, there are many employees who move from facility to facility or
even from industry to industry. In fact, a substantial number, like contract
nurses, will work in several facilities at one time. A universal sign will
enable these employees to recognize the hazard wherever it occurs and then
take proper precautions. The issue of whether OSHA should specify colors that
must be included on the sign was raised at TB stakeholder meetings. OSHA
realizes there is a part of the population, perhaps as high as 10 % of all
men, that is color blind and that at some work sites some colors have been
employed that are different from the red that OSHA proposes be used. However,
stakeholders, particularly those whose jobs took them to several different
work sites, urged OSHA to require a standardized sign and, of those who
considered the issue, there was general agreement that the red on the
familiar "stop" sign was appropriate. OSHA has preliminarily
concluded that the colors required provide needed warning even though not all
employees (e.g., those who are color blind) may benefit from them, and
that the colors chosen are consistent with conventions on health signage. The
Agency has developed a sign that it believes will provide appropriate warning
and be easily recognizable. Failing to find either a guideline recommendation
or a generally accepted community standard regarding what sign should be
placed at the entrances to these areas, OSHA looked to generic, broad-based
sources for symbols which would be easily identifiable, understandable to
workers who were not able to read well or are non-English speaking, and
simple to construct. In
paragraph (h)(2)(iii), therefore, OSHA is proposing that a "STOP"
sign with the accompanying legend, "No Admittance Without Wearing A Type
N95 Or More Protective Respirator", meets these criteria. The sign is
easily recognizable, requires a simple color scheme, and should be
understandable to employees with minimal training. OSHA
is seeking information on the effectiveness of the proposed sign to warn
workers of the presence of a hazard, as well as information on other signs
that may be more effective. Please be specific when providing information,
keeping in mind the wide variety of work sites where signs will be needed. Where
an alternative is being proposed, please enclose a model or drawing as well
as the rationale for believing that it will be more effective than OSHA's
proposed sign. Paragraph
(h)(2)(iv) requires that signs at the entrances of clinical or research
laboratories and autopsy suites where procedures are being performed that may
generate aerosolized M. tuberculosis include the biohazard symbol,
name and telephone number of the laboratory director or other designated
responsible person, the infectious agent designation "Mycobacterium
tuberculosis", and special requirements for entering the laboratory
or autopsy suite. This provision has been taken directly from the CDC/NIH
publication "Biosafety in Microbiological and Biomedical
Laboratories" (Ex. 7-72). As previously discussed, the purpose for this
sign is to warn employees of the potential TB hazard and inform them of
precautions that must be taken to prevent exposure. Information
and Training It
is OSHA's position that employees must understand the nature of the hazards
in their workplace and the procedures to follow in order to eliminate or
minimize their risks of exposure to these hazards. (Exs. 4-B, 7-169, 7-170,
7-61, 7-64) In the case of M. tuberculosis, employee exposures may
result in a TB infection, which may ultimately result in disease and even
death. The provisions in paragraph (h)(3) of this proposed standard set forth
the training that each employer must provide to his or her employees. OSHA
believes that effective training is a critical element in any occupational
safety and health program. In this proposed standard, the employer would be
required to provide training for each employee covered by the scope of the
standard. Paragraph
(h)(3)(i) requires that employers assure that each employee with occupational
exposure participates in training, which must be provided at no cost to the
employee and be made available at a reasonable time and place. Since
appropriate training is considered to be critical in assuring employee
protection, the employer is responsible for making sure that each employee
with occupational exposure participates in the training program. Having the
employee pay in some manner for all or part of the training or requiring the
employee to attend training at an unreasonable time and place would be a
disincentive to participation. If training cannot feasibly be provided during
work hours, employees are to be paid for training scheduled outside of normal
working hours. In
view of the importance of training, OSHA is proposing that it be provided at
several particular points in time. (Exs. 7-169; 4-B) More specifically,
paragraph (h)(3)(ii) requires that training be provided: (A) before initial
assignment to tasks where occupational exposure may occur, for those
employees without previous occupational exposure; (B) within 60 days after
the effective date of the final standard, for those employees who have
occupational exposure at the time of the standard's promulgation; and (C) at
least annually thereafter, unless the employer can demonstrate that the
employee has the specific knowledge and skills required under paragraph
(h)(3)(vii). The employer must provide re-training to an employee in any of
the topic(s) in paragraph (h)(3)(vii) in which that employee cannot
demonstrate the necessary knowledge and/or skill. This approach to training
frequency assures that employees entering jobs with occupational exposure
will be fully trained before exposure occurs. In addition, employees who are
already working in jobs with occupational exposure at the time of the
standard's promulgation will receive training and must become knowledgeable
in all of the required aspects of the standard (e.g., employer's
exposure control plan, medical surveillance program, warning signs and
labels) within a short period of time. Annual
re-training reinforces the initial training and provides an opportunity to
present new information that was not available at the time of initial
training. The Agency recognizes that, as a result of training previously
provided by the employer, employees may possess some of the knowledge and
skills listed in the training topics in paragraph (h)(3)(vii). Consequently,
OSHA is proposing that re-training be provided annually unless the employer
can demonstrate that the employee has the specific knowledge and skills
required by this paragraph. The employer must provide re-training to an
employee in any topic(s) in paragraph (h)(3)(vii) in which the employee
cannot demonstrate specific knowledge and skills. An
employee with occupational exposure to TB who moves to a job with another
employer that also involves occupational exposure to TB would not need to
meet all of the initial training requirements. In such instances, the Agency
has determined that the employee's prior training in the general topics
required by the standard (e.g., the general epidemiology of tuberculosis,
the difference between tuberculosis infection and tuberculosis disease) would
remain relevant in the new work setting and that the new employer need not
re-train in these topics. However, the employee would not possess knowledge
of the topics required by the standard that are specific to the new
employer's particular work setting (e.g., the new employer's exposure
control plan and respiratory protection program and the means by which the
employee could access the written plans for review). OSHA is proposing to
permit limited "portability" of training, as noted in the standard.
This note states that training in the general topics listed in paragraph
(h)(3)(vii) that has been provided in the past 12 months by a previous
employer may be transferred to an employee's new employer. However, the new
employer must provide training in the site-specific topics listed in
paragraph (h)(3)(vii) in accordance with the requirements of paragraph (h) (e.g.,
at no cost to the employee and at a reasonable time and place). OSHA
is aware that some employers have already established training for their
occupationally exposed employees. (Ex. 7-169) In light of this, paragraph
(h)(3)(iii) of the proposed standard requires only that limited training be
conducted for those employees who already have received training on
tuberculosis in the year preceding the effective date of the standard. The
additional training would only have to address those provisions of the
standard not previously covered in the earlier training. The
requirement for annual training within one year of the employee's previous
training, in paragraph (h)(3)(iv), assures that each employee receives
training within 12 calendar months of his or her last training. Annual
training is not based on a calendar year; that is, training will not be
permitted to be provided to an employee in January of one year and in
December of the following year, essentially a 23-month span between training
sessions. Employers may establish schedules for training around this
requirement. Also,
paragraph (h)(3)(v) stipulates that the employer must provide additional
training whenever changes in the occupational environment, such as
modification of tasks or procedures or institution of new tasks or
procedures, affect the employee's occupational exposure to M. tuberculosis.
This provision will assure that employees remain apprised of any new exposure
hazards and the precautions necessary to protect themselves from exposure. This
additional training does not need to entail a complete reiteration of the
annual training, but may be limited to addressing the new sources of
potential exposure. The
proposed standard requires that training material be used that is appropriate
in content and vocabulary to the educational level, literacy and language of
employees. Employees must be able to comprehend the information being
conveyed in order for it to be useful. Therefore, the employer has the
responsibility for assuring that the training is provided in an
understandable manner to the audience being addressed. This provision would
assure that employees, regardless of their educational or cultural
background, will receive adequate training. Paragraph
(h)(3)(vii) of the proposed standard contains the specific elements that
would comprise a minimum training program. (Exs. 4-B; 7-169; 7-64) The
provisions for employee training are performance oriented, stating the
categories of information to be transmitted to employees and not the specific
ways that this is to be accomplished. This assures that important information
is communicated to employees about the nature of this occupational hazard
while allowing employers the most flexible approach to providing training. OSHA
has set forth the objectives to be met and the intent of training. The
specifics of how the employer assures that employees are made aware of the
hazards in their workplace and how they can help to protect themselves are
left up to the employer who is best qualified to tailor the training to the
TB hazards in his or her workplace. The
proposed standard would require the employer to explain a number of
particular topics in the training session(s). Paragraph (h)(3)(vii)(A)
requires the employer to provide an explanation of the contents of this
standard and the location of an accessible copy of the regulatory text and
appendices to this standard. This enables the employee to have access to the
standard and to become familiar with its provisions. It is not necessary for
the employer to provide each employee with a copy of the standard; it is
sufficient for the employer simply to make a copy accessible. For example, a
copy of the standard could be posted in a location where it could be readily
and easily viewed by employees. An
important element in the training involves an overview of the epidemiology of
tuberculosis, the pathogenesis of the disease and an explanation of various
aspects of risk to employees. (Ex. 4B) More specifically, paragraph
(h)(3)(vii)(B) requires that the training include an explanation of: the
general epidemiology of tuberculosis, including multidrug-resistant TB and
the potential for exposure in the facility; the signs and symptoms of TB,
including the difference between TB infection and TB disease; the modes of
transmission of tuberculosis, including the possibility of reinfection in
persons with a positive tuberculin skin test; and the personal health
conditions that increase an employee's risk of developing TB disease if
infected. Since
the employer can tailor the training to the needs of his or her employees,
the training program will likely be more technical for some audiences and
less technical for others. The general goal of this paragraph is to assure
that each employee being trained understands what tuberculosis is, how it is
spread, and possible risks that may affect the employee. Employees
need to be able to recognize symptoms associated with TB disease. (Ex. 4B)
The employee must understand that certain symptoms (e.g., a persistent
cough lasting 3 or more weeks, bloody sputum, night sweats, anorexia, weight
loss, fever) may be related to TB. In addition, information on
non-occupational risk factors that place employees at increased risk of
developing tuberculosis disease following an infection permits those
individuals at increased risk to make informed decisions about their
employment situations. Paragraph
(h)(3)(vii)(C) requires an explanation of the employer's exposure control
plan and respiratory protection program. Employees must also be informed
about what steps they need to take to review the written plans, if they so desire. Paragraph
(h)(3)(vii)(D) requires the employer to train employees regarding the tasks
and other activities that may involve occupational exposure to tuberculosis. Employees
must be made aware of those job duties which may expose them to tuberculosis.
For example, although certain health care professionals may easily recognize
the hazard involved in transporting a person with infectious TB, the staff of
a correctional facility may not. On the other hand, some health care
professionals may not immediately recognize that their mere presence in a
room where an individual with suspected or confirmed infectious TB is being
X-rayed presents an exposure risk and necessitates wearing a respirator. All
occupationally exposed employees need training that will enable them to
recognize those activities that put them at risk of exposure. Paragraph
(h)(3)(vii)(E) of this section requires employers to train employees
regarding both the uses and limitations of various control measures,
specifically those used at the employees' worksite. Exposed employees must be
familiar with the employer's tuberculosis policies and procedures in order
for them to be properly implemented. Control of exposure frequently involves
using a variety or combination of engineering controls, administrative
controls, work practice procedures and personal protective equipment. To
assure that employees will be able to identify and implement methods of
reducing occupational exposure to tuberculosis, they must understand how
these controls are applied in their work sites and the limitations thereof. With
this understanding, employees will be more likely to use the appropriate
control for the situation at hand and to use it correctly. For example,
employees must be able to recognize the labels and signs used to identify
rooms or areas where suspected or confirmed infectious individuals are
present so that they can take appropriate precautions before entering. Understanding
of the limitations of control measures will also enable employees to
recognize when inappropriate or inadequate control measures have been taken
and increases the likelihood that they will report such situations. Training
must be relevant to the specific site where the employee will be working. Each
employee must know, for example, the procedures used in his or her particular
facility to identify suspected infectious TB cases, where respiratory
protection is kept, and what engineering controls are in place within the
facility. This training is particularly important for workers who move
between several facilities in the course of their work, for example,
"leased" personnel, part-time employees, "moonlighters",
or contractors. The
provision covering the selection, types, proper use, location, removal and
handling of respiratory protection, paragraph (h)(3)(vii)(F), is particularly
important because many of the employees and employers proposed to be covered
by the tuberculosis standard may not be accustomed to the use, selection, and
upkeep of respiratory protection. Consequently, training on aspects such as
the necessity for respiratory protection, the appropriate type of respiratory
protection, where to obtain it, and its proper use, fit, and the general
upkeep is necessary to assure the effectiveness of respirator use. (Ex. 7-64) OSHA
believes that employees who have a clear understanding of the medical
surveillance program (its purpose, methodology, and the significance of the
results of examinations and tests), will be much more likely to participate
in that program. Therefore, paragraph (h)(3)(vii)(G) requires that the
training include an explanation of the employer's medical surveillance
program, including the purpose of tuberculin skin testing, the importance of
a positive or negative skin test result, anergy testing, and the importance
of participation in the program. This increased participation by trained
employees helps the employee to identify changes in his or her personal
health status and also aids the employer in assessing the effectiveness of
his or her TB control program. Each
employee must understand the actions to be taken if an occupational exposure
occurs as well as what is available to them regarding appropriate medical
treatment, prophylaxis, and post exposure follow-up in order for the employee
to lessen the chance of developing active disease. Therefore, paragraph
(h)(3)(vii)(H) would require an explanation of the procedures to follow if an
exposure incident occurs, including the method of reporting the incident, an
explanation of the medical management and follow-up that the employer is
required to provide, and the benefits and risks of drug prophylaxis. In
addition, the employee must be provided with an explanation of the procedures
to follow if the employee develops signs or symptoms of tuberculosis disease
[paragraph (h)(3)(vii)(I)]. In this way, an employee who notes the signs or
symptoms of personal disease development will be aware of the appropriate
steps to take, thereby speeding initiation of medical evaluation. Quick
evaluation protects the employee, co-workers, and the public. In
paragraph (h)(3)(viii), the proposed standard mandates that the person
conducting the training must be knowledgeable in the subject matter as it
relates to the specific workplace being addressed. OSHA believes that a
variety of persons are capable of providing effective training to employees. OSHA
has approached this section of the proposed standard in much the same way as
the trainer requirements were addressed in the standard for Occupational
Exposure to Bloodborne Pathogens. That is, a knowledgeable trainer is one who
is able to demonstrate expertise in the area of the occupational hazard of
tuberculosis and is familiar with the manner in which the elements of the
training program relate to the particular workplace. A
number of resources are available through the Centers for Disease Control and
Prevention and professional organizations such as the American Lung
Association and the American Thoracic Society that can be used to educate
trainers and prepare them for this task. In addition, specialized training
courses in the area of tuberculosis control can also assist in educating
trainers (Ex. 7-189). In
addition to general knowledge of the subject matter, it is important that the
trainer be able to instruct the participants in site-specific features of the
Exposure Control Plan that will reduce their risk in the particular facility.
This benefits not only employees within the facility but also provides
temporary employees with the information needed to protect themselves against
exposure while working in the facility. For example, workers who have
received general training by their employer (e.g., a personnel
staffing agency) will also receive training about the facility where they
will actually perform their duties (e.g., a specific hospital). An
important component of an effective learning experience is the opportunity
for the learner to interact with the trainer for the purposes of asking
questions and obtaining clarification. Paragraph (h)(3)(ix) would require
that the employer provide employees with this opportunity as part of the
training program. The trainer must be available at the time that the training
takes place. OSHA would expect that in most instances, the individual who
would provide answers to the employee's question would be physically present
when the employee is trained. The Agency does recognize, however, that there
may be some instances where this is not possible. In these cases, it would be
acceptable for the employee to ask questions by telephone. An
employer would not be expected to train employees in site-specific topics
that are not applicable to the employer's work setting. For example, if a
facility was not required by the standard to utilize engineering controls,
the employer would not be responsible for training his or her employees about
the various aspects of engineering controls. OSHA
believes that the information and training requirements incorporated into
this proposed standard are needed to inform employees about the hazard of
tuberculosis and to provide employees with an understanding of the degree to
which they can minimize the health hazard. Training is essential to an
effective overall hazard communication program and serves to explain and
reinforce the information presented to employees on signs and labels. These
forms of information and warning will be meaningful only when employees
understand the information presented and are aware of the actions to be taken
to avoid or minimize exposure. OSHA
seeks comment on the proposed content of the training program and requests
that model TB training programs be submitted to the docket, particularly
those designed for audiences whose participants may have language
difficulties or have no health care background, and those that have been
judged to be successful in communicating information to employees. It is
OSHA's intent, upon publication of the final standard, to include information
on training programs in compliance guides to be developed for small entities. Paragraph (i) Recordkeeping This
proposed standard requires employers to keep records related to TB, including
medical surveillance and training records for all employees with occupational
exposure and engineering control maintenance and monitoring records. OSHA has
made a preliminary determination that, in this context, medical and training
records are necessary to assure that employees receive appropriate
information on hazards and effective prevention and treatment measures, as
well as to aid in the general development of information on the occupational
transmission of TB. Specifically, OSHA believes that maintenance of medical
records is essential because documentation is necessary to ensure proper
evaluation of an employee's infection status and for prompt and proper
healthcare management following an exposure incident. OSHA has also
preliminarily determined that maintenance and monitoring records for
engineering controls are necessary for two reasons: to enable the employer to
know that the control methods remain in good working order so as to assure
their effectiveness and to aid the Agency in enforcement of the standard. In
paragraph (i)(1), OSHA proposes to require employers to establish and
maintain a medical record in accordance with 29 CFR 1910.1020 for each
employee with occupational exposure to TB. The record must include: (A) The
name, social security number, and job classification of the employee; (B) A
copy of all results of examinations, medical testing, including the
employee's tuberculin skin test status; and follow-up procedures required by
paragraph (g); (C) The employer's copy of the physician's or other licensed
health care professional's written opinion as required by paragraph (g)(7);
and (D) A copy of the information provided to the physician or other health
care professional required by paragraph (g)(6). The information that must be
included in the medical record is necessary for the proper evaluation of the
employee's infection status and management of occupational exposure
incidents. This record will aid OSHA in enforcing the standard and the
information therein, when analyzed, will further the development of health
data on the causes and prevention of occupational transmission of TB. Similar
provisions for collection and retention of such information have been
included in other OSHA health standards including, most recently, Bloodborne
Pathogens (29 CFR 1910.1030) and Cadmium (29 CFR 1910.1027). In
paragraph (i)(1)(iii), OSHA is proposing to require that the employee medical
records be kept confidential and not be disclosed or reported to anyone
without the employee's express written consent except as required by section
i or as may be required by law. In nearly every health standard rulemaking,
employees have told the Agency that keeping medical records confidential is
extremely important to them. Employees stated that, without assurance of
confidentiality, they would be reluctant to participate in medical
surveillance, a predicament that would be detrimental to their health and
could affect health and safety conditions in the workplace. During the
Bloodborne Pathogens rulemaking, confidentiality of medical records was a
major issue due to the nature of the diseases addressed. Of particular
concern was keeping the medical records from being disclosed to the employer.
It was explained in the Bloodborne Pathogens standard and is applicable here
that such confidentiality can be accomplished by having the records kept by
the physician or other licensed health care provider at the expense of the
employer. In those cases where the employer is the health care provider, the
records can be maintained separately from other employee records so that
disclosure can be strictly limited to the physician or other licensed health
care professional and his or her staff who are responsible for the medical
management of the employee. It was pointed out in the preamble to the
Bloodborne Pathogens standard, and bears repeating here, that the
confidentiality provisions in the proposed standard are reiterations of
existing standards of conduct in the health care professions and that the
OSHA requirements do not abridge, enlarge or alter existing ethical or
statutory codes (56 FR 64170). This section of the proposal requires that
medical records be disclosed to the Assistant Secretary or the Director (of
NIOSH) and as may be required by law, which means that this proposed standard
would not prevent employers from reporting TB cases to federal, state, or
municipal health departments where that reporting is required by law. Paragraph
(i)(1)(iv) proposes to require that medical records be maintained in
accordance with 29 CFR 1910.1020 for at least the duration of employment plus
30 years. The Access to Medical Records Standard contains an exception to the
30-year requirement that provides that the medical records of an employee who
has worked less than one year must be maintained throughout his or her
employment, but need not be retained afterwards as long as they are given to
the employee upon termination of employment. Maintaining the records for the
duration of employment serves several purposes: the records can provide
valuable information to the employee's healthcare provider; the records
enable the employer to know that employees are benefitting from regular
surveillance and timely intervention following occupational exposure to TB;
analysis and aggregation of the records can provide insight into the causes
and consequences of occupational exposure to TB; and, the records will aid in
the enforcement of the standard. Requiring the records to be kept 30 years
beyond employment is necessary because TB can have a long incubation period,
with disease often appearing only many years after initial infection. This
retention time is also consistent with other OSHA health standards (See for
example Benzene, 29 CFR 1910.1028; Bloodborne Pathogens, 29 CFR 1910.1030;
Ethylene Oxide, 29 CFR 1910.1047). In
paragraph (i)(2), OSHA proposes to require employers to record TB infection
and disease in accordance with 29 CFR 1904, Recording and Reporting
Occupational Injuries and Illnesses, and 29 CFR 1960, the equivalent
requirement for Federal Agency programs. This should not be an unfamiliar
requirement to employers because occupational TB infections and disease must
be reported in accordance with 29 CFR 1904 and 29 CFR 1960, as directed by current
OSHA enforcement policy (Ex. 7-1). In
paragraph (i)(3), OSHA proposes to require training records, which include:
(A) The dates of the training sessions; (B) The contents or a summary of the
training sessions; (C) The names and qualifications of persons conducting the
training; and (D) The name and job classification of all persons attending
the training sessions. This requirement is consistent with other OSHA
standards, particularly Bloodborne Pathogens, and it represents the minimum
amount of information an employer, an employee, or an OSHA compliance officer
would need in order to determine when and what training had been provided,
who administered it and who attended. Additionally, such a record is an
invaluable aid to the employer when evaluating his or her training program. OSHA
proposes, in paragraph (i)(3)(ii) to require that training records be
maintained for three years beyond the date the training occurred. The Agency
anticipates that employers will not have difficulty maintaining the records
for three years because the information to be included is not extensive and
many employers are already keeping training records three years as required
by other OSHA standards (e.g., Bloodborne Pathogens, 29 CFR
1910.1030). Moreover, these records are not required to be kept confidential
and so may become part of an employee's personnel file or part of a larger
file, at the discretion of the employer. In
paragraph (i)(4), OSHA proposes to require engineering control maintenance
and monitoring records be kept that include: (A) Date; (B) Equipment
identification; (C) Task performed; and (D) Sign-off. The performance
monitoring records must include: (A) Date and time; (B) Location; (C)
Parameter measured; (D) Results of Monitoring; and (E) Sign-off. Only two of
these items will require more than a few words or numbers to record; the two
items that require more extensive information are the maintenance task
performed and the results of the performance monitoring. Where the employer
has not already developed a method for recording the task performed, the
maintenance person can list the tasks or use a previously prepared
check-list. The results of performance monitoring can be recorded in the same
way or another way that meets the needs of the particular workplace so long
as it includes all of the information required by the paragraph. OSHA
believes that the information in these records is the usual data that are
generated by persons maintaining and servicing equipment so that the status
of the equipment and its effectiveness can be known for a given time. The
information is also useful in determining when further servicing is needed. Proposed
paragraph (i)(4)(iii) requires engineering control maintenance and monitoring
records to be maintained for three years. The three year period is a
reasonable period of time and it will enable the employer to develop and
sustain a proper maintenance program and to track the effectiveness of the
controls. Moreover, the records will aid the OSHA compliance officer in
enforcing the standard's requirements for engineering controls. Availability
of medical records is specified in section 8(c) of the Act. In paragraph
(i)(5) of this standard, OSHA proposes to restrict the availability of
employee medical records while making employee training records and
engineering control and monitoring records generally available upon request. Medical
records must be provided to the subject employee, to anyone having written
consent from the employee, to the Director and to the Assistant Secretary in accordance
with 29 CFR 1910.1020, which sets forth the procedures that will protect the
privacy concerns of the employees. This paragraph does not affect existing
legal and ethical obligations concerning maintenance and confidentiality of
employee medical records. An employer's access is governed by existing
federal, state and local laws and regulation. This standard, like Bloodborne
Pathogens (29 CFR 1910.1030) and other OSHA standards, limits employer access
to confidential information while allowing the employer access to the
information needed to make appropriate decisions relative to his or her
medical surveillance program. For example, paragraph (g)(7)(ii) limits the
information that can be included in the physician's or other licensed health
care professional's written opinion and paragraph (g)(7)(iii) requires that
other medical diagnoses or findings be kept confidential. There is no
language in this proposed standard that grants an employer access to the
confidential information in an employee's medical file. OSHA illness and
injury records are accessible under 29 CFR 1904 and 29 CFR 1960, as
appropriate, to the facility. In this proposal, as in OSHA's other health
standards, training records and engineering control maintenance and
monitoring records are to be provided upon request to the employees, their
representatives, the Director and the Assistant Secretary. Employers should
not have difficulty complying with this provision because most will have
experience with such recordkeeping from other standards. There are no
confidentiality issues raised by these records. In
paragraph (i)(6), an employer who goes out of business is required to
transfer medical records as set forth in 29 CFR 1910.1020(h) and 29 CFR 1904,
which address the transfer of medical records. Specifically, medical records
must be transferred to a successor employer who must accept them and keep
them in accordance with the requirements of 29 CFR 1910.1020. In the event
the employer ceases to do business and there is no successor employer, the
employer is required to notify the Director, at least three months prior to
disposal of the records, and transmit them to the Director if required by the
Director to do so. This is consistent with other health standards and ensures
that a successor employer (and the employees) can benefit from the
information contained in the records. The reason the records are transferred
(if requested) to the Director of NIOSH is that NIOSH has a vested interest
in maintaining records of occupational injuries and illnesses and is in an
excellent position to decide how the records can be best used to be of value
to the exposed employee, subsequent employees in the field and OSHA. At
NIOSH, the records remain confidential as required by 29 CFR 1910.1020(e). Thus,
only the employee or his or her representative with the permission of the
employee retains access to the medical records transferred to NIOSH. Paragraph (j) Definitions Acid-Fast Bacilli (AFB) means bacteria that retain certain dyes after being washed in an acid
solution. Most acid-fast organisms are mycobacteria. Smears of sputum samples
and other clinical specimens may be stained with dyes to detect acid-fast
mycobacteria such as M. tuberculosis. However, AFB smear tests cannot
distinguish one type of mycobacteria from another. Therefore, as noted by
CDC, when AFB are seen on a stained smear of sputum or other clinical
specimens, a diagnosis of TB should be suspected; however, the diagnosis of
TB is not confirmed until a culture is grown and identified as M. tuberculosis
(Ex. 4B). Accredited Laboratory for purposes of this standard means a laboratory that has
participated in a quality assurance program leading to a certification of
competence administered by a governmental or private organization that tests
and certifies laboratories. Under the medical surveillance provisions of the
proposed standard, paragraph (g)(1)(iv) requires that all laboratory tests
required by the standard be conducted by an accredited laboratory. This
definition makes clear OSHA's intent about the type of laboratory that would
be required to conduct these types of tests. The
term AFB Isolation Room or Area refers specifically to the rooms or
areas where individuals with suspected or confirmed infectious TB are
isolated. For purposes of this standard this term includes, but is not
limited to, rooms, areas, booths, tents or other enclosures that are
maintained at negative pressure relative to adjacent areas in order to
control the spread of aerosolized M. tuberculosis. Such rooms or areas
are able to contain droplet nuclei through unidirectional airflow into the
room (i.e., negative pressure). A definition of negative pressure is
presented below and a more detailed explanation can be found in the Summary
and Explanation of paragraph (d), Work Practices and Engineering Controls. Anergy
means the inability of a person to react to skin test antigens (even if the
person is infected with the organism(s) tested because of immunosuppression. More
specifically, an anergic individual's immune system has become so compromised
that it is unable to mount a sufficient reaction to the test organism. Because
of their inability to respond immunologically, persons with anergy will have
a negative tuberculin skin test even if they are infected with M.
tuberculosis. Therefore, as noted by the CDC, it may be necessary to
consider other epidemiologic factors (e.g., the proportion of other
persons with the same level of exposure who have positive tuberculin skin
test results and the intensity or duration of exposure to infectious TB
patients that the anergic person experienced) when making a determination as
to whether that anergic individual has been infected with M. tuberculosis
(Ex. 4B). As discussed under paragraph (g)(2)(iii), Medical Surveillance,
tuberculin skin testing is to include anergy testing when the physician or
other licensed health care professional, as appropriate, determines such
testing is necessary. Knowing which individuals are anergic will help to
determine those situations where information other than skin test status will
need to be ascertained and considered in order to assess the likelihood of
infection for exposed employees. Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and
Health, or designated representative, and is a definition consistent across
all OSHA standards. BCG (Bacille Calmette-Guerin) vaccine means a tuberculosis vaccine used in many
parts of the world. Because of its variable efficacy and its impact upon
tuberculin skin tests (i.e., making skin test interpretation more difficult),
routine BCG vaccination is not currently recommended in the United States
(Ex. 7-50). However, many foreign countries still use BCG as part of their
tuberculosis control programs, especially for infants (Ex. 7-72). Since
individuals vaccinated with BCG may have a tuberculin skin test that cannot
be distinguished reliably from a reaction caused by infection with M.
tuberculosis, it is helpful to know whether an individual has been
vaccinated with BCG and when such vaccination occurred. Thus, under the
medical surveillance provisions of the proposed standard, the medical history
is to include a history of BCG vaccination. Cartridge or canister means a container with a filter, sorbent, or catalyst, or a
combination of these items, that removes specific air contaminants from the
air drawn through the container. With respect to this standard, respirators
would be equipped with cartridges or canisters containing particulate
filters. Clinical laboratory has been defined for purposes of this standard as a facility or an
area of a facility that conducts routine and repetitive operations for the
diagnosis of TB, such as preparing acid-fast smears and culturing sputa or
other clinical specimens for identification, typing or susceptibility
testing. This definition is meant to apply to laboratories where routine
diagnostic tests for TB are conducted as compared to research laboratories
where M. tuberculosis may be cultured in large volumes or concentrated
for research or commercial production. Clinical laboratories may be located
within facilities such as hospitals or clinics, or they may be freestanding
facilities. Confirmed infectious tuberculosis (TB) means a disease state that has been
diagnosed by positive identification of M. tuberculosis from body
fluid or tissue through positive culture, positive gene probe, or positive
polymerase chain reaction (PCR); and the individual is capable of transmitting
the disease to another person. The disease state may be manifested as
pulmonary or laryngeal TB or extrapulmonary TB if the infected tissue is
exposed and could generate droplet nuclei. As
discussed under the definition for AFB, a positive AFB smear indicates only
that an individual has an identifiable mycobacterium. The three methods
listed here provide positive confirmation of M. tuberculosis. In
addition, the definition states that the disease state must be capable of
being transmitted to another person (i.e., infectious). This provision of the
definition is to differentiate this state of the disease from other active
forms of TB disease where the individual is not infectious. For example, an
individual may contract active TB disease and become infectious. After
adequate drug therapy has been initiated the individual may become
noninfectious, at which point he or she cannot transmit the disease to other
individuals. However, the individual, while no longer infectious, still has
active disease and must continue treatment for several months because living
bacilli are still in his or her body. The definition also states that the
disease may be manifested as pulmonary or laryngeal TB or extrapulmonary TB
if the infected tissue is exposed and could generate droplet nuclei. In most
cases, it is the pulmonary or laryngeal forms of infectious TB that present a
risk of infection for other individuals. This is due to the fact that
tuberculosis bacilli in the pulmonary or laryngeal tracts may be easily
dispelled when infectious individuals cough or speak. Other body sites
infected with the bacilli, i.e., extrapulmonary TB, do not present an
infection hazard in most cases because the bacilli are not capable of being
dispelled outside the body. However, in some situations, such as a lesion or
an abscess where the infected tissue is exposed, there may be a risk of
transmission of disease when certain procedures are performed (e.g.,
tissue irrigation) that could generate droplet nuclei containing the bacilli. Conversion
means a change in tuberculin skin test results from negative to positive,
based upon current Centers for Disease Control and Prevention (CDC)
guidelines. Under paragraph (g), the employer is required to provide medical
management and follow-up to employees who have converted to positive
tuberculin skin test status (e.g., providing preventive therapy, if
appropriate, and conducting follow-up investigations of circumstances
surrounding the conversion). Since a number of specific actions are required
of the employer as a result of a conversion, it is necessary that conversions
be correctly identified. An important part of this identification is the
interpretation as to whether an employee has a positive skin test response. As
such, this definition states that the interpretation of the positive reaction
should be based upon current CDC guidelines (Ex. 4B). It is not OSHA's intent
to define what should constitute a positive reaction, but rather to assure
that such determinations are made using currently accepted public health
guidelines. Director
means the Director of the National Institute for Occupational Safety and
Health, U.S. Department of Health and Human Services, or designated
representative. Similar to the definition for Assistant Secretary, the
definition for Director is consistent across OSHA standards. Disposable respirator means a respiratory protective device that cannot be resupplied with
an unused filter or cartridge and that is to be discarded in its entirety
after its useful service life has been reached. In general, the facepiece of
these respirators is constructed from the particular filter media of interest
(e.g., particulate filter). Exposure incident for purposes of this standard means an event in which an employee has
been exposed to an individual with confirmed infectious TB or to air
containing aerosolized M. tuberculosis without the benefit of all of
the applicable exposure control measures required by this section. This
definition is limited to those situations involving exposure to an individual
with confirmed infectious TB or air originating from an area where a source
of aerosolized M. tuberculosis is present; it does not include
exposure to individuals with suspected infectious TB. OSHA has limited the
definition in this way because several provisions in the proposed standard
are triggered by the occurrence of an exposure incident. For example, under
paragraph (g), Medical Surveillance, the employer is required to
provide additional tuberculin skin testing to each affected employee and to
investigate and document the circumstances surrounding each exposure incident
to determine if changes can be instituted to prevent similar occurrences in
the future. OSHA believes that it would be burdensome and unnecessary for the
employer to conduct follow-up investigations for those occurrences where an
employee's exposure is to an individual suspected of having infectious TB but
for whom infectious disease is subsequently ruled out. An
example of an exposure incident is an employee entering an AFB isolation room
or area occupied by an individual with confirmed infectious TB without the
employee wearing appropriate personal respiratory protection equipment. This
occurrence would not be defined under the standard as an exposure incident if
the individual in the AFB isolation room had only suspected infectious TB. If
the individual in AFB isolation room was later confirmed to have infectious
TB, the employee entering the isolation room without appropriate respiratory
equipment would then be considered to have had an exposure incident and the
required medical management and follow-up provisions for an exposure incident
under paragraph (g), Medical Surveillance, would be required. Another
example of an exposure incident is a failure of engineering controls, e.g.,
the ventilation system in an AFB isolation room housing an individual with
confirmed infectious TB malfunctioned, negative pressure was lost, and air
containing M. tuberculosis was dispelled into the hall corridor,
exposing unprotected employees. Although OSHA would consider this type of
loss of negative pressure in an AFB isolation room to be an exposure
incident, the Agency does not intend that each opening of the door to an AFB
isolation room be considered an exposure incident, even though some loss of
negative pressure may result when the door to an AFB isolation room is
opened. As a practical matter, OSHA believes it would be infeasible to
consider every instance that a door to an isolation was opened as an exposure
incident. In addition, these losses of negative pressure are generally small,
if doors are kept open only briefly for purposes of entry and exit and are
kept closed at all other times while the room is in operation for TB
isolation as required under the Work Practices and Engineering Controls
paragraph (d)(5)(vi). There
is a significant difference in the meaning of the terms "exposure
incident" and "occupational exposure" as they are used in this
standard. This difference is discussed further under the definition of
"occupational exposure". Filter
means a component used in respirators to remove solid or liquid aerosols from
the inspired air. The filter is the medium that captures the aerosol,
preventing it from passing through to the respirator wearer. Fit factor
is a quantitative measure of the fit of a particular respirator on a
particular individual. Fit factor is derived from the ratio of the
concentration of a challenge agent (or air pressure) outside of the
respirator to the concentration of the test agent (or air pressure) inside the
respirator. High Efficiency Particulate Air (HEPA) Filter means a specialized filter that
is capable of removing 99.97 percent of particles greater than or equal to
0.3 micrometer in diameter. High-hazard procedures are those procedures performed on an individual with suspected or
confirmed infectious tuberculosis in which the potential for being exposed to
M. tuberculosis is increased due to the induction of coughing or the
generation of aerosolized M. tuberculosis. Such procedures include, but are
not limited to, sputum induction, bronchoscopy, endotracheal intubation or
suctioning, aerosolized administration of pentamidine or other medications,
and pulmonary function testing. They also include autopsy, clinical, surgical
and laboratory procedures that may aerosolize M. tuberculosis. The
procedures listed above present a high hazard because they are performed on
individuals with suspected or confirmed infectious TB or on specimens or
deceased individuals where M. tuberculosis may be present. For
example, some of the procedures listed above, such as bronchoscopies and
pentamidine administration, cause people to cough. For individuals with
pulmonary TB, coughing will increase the likelihood that they will generate
aerosols with a high concentration of droplet nuclei. In addition, certain
autopsy procedures, such as cutting into a lung containing M. tuberculosis,
and certain laboratory procedures, such as processing infected tissue samples
with pressurized freezants, can generate aerosols containing droplet nuclei. In
the absence of M. tuberculosis, these procedures would not be
high-hazard. For example, endotracheal intubation on an individual who does
not have suspected or confirmed infectious TB would not be considered a
high-hazard procedure. M. tuberculosis means Mycobacterium tuberculosis, the scientific name of the
bacillus that causes tuberculosis. Negative Pressure means the relative air pressure difference between two areas. A room
that is under negative pressure has lower pressure than adjacent areas, which
keeps air from flowing out of the room and into adjacent rooms or areas. Paragraph
(d)(5)(i) of Work Practices and Engineering Controls requires that negative
pressure be maintained in all AFB isolation rooms or areas, and paragraph
(d)(4) requires that all high-hazard procedures be performed in such rooms or
areas. Maintaining negative pressure in such rooms or areas helps to assure
that droplet nuclei are contained and not spread to other areas of the
facility where unprotected employees may be exposed. A further discussion of
this principle can be found in the Summary and Explanation of paragraph (d),
Work Practices and Engineering Controls. Negative pressure respirator means a respirator in which the air pressure
inside the facepiece is negative during inhalation with respect to the
ambient air pressure outside the respirator. In a negative pressure
respirator, the wearer's inhalation creates a drop in pressure inside the
facepiece, consequently drawing outside air through the filter and into the respirator. Occupational exposure is one of the key terms upon which the proposed standard rests. It
contains the criteria that trigger application of the standard for employees
in work settings covered under the scope of the standard as listed in
paragraphs (a)(1) through (a)(8) and for employees providing the care and
services listed in paragraphs (a)(9) and (a)(10). Although a variety of work
settings and several specific types of work are covered within the scope of
the standard, it is only employees who have "occupational exposure"
in those work settings and who are providing the particular services that
must be given the protection mandated by the standard. The exception to this
is that an employer covered under paragraph (a), scope, must provide
medical management and follow-up to other employees who have an exposure
incident. For
purposes of this standard, occupational exposure means reasonably anticipated
contact, which results from the performance of an employee's duties, with an
individual with suspected or confirmed infectious TB or air that may contain
aerosolized M. tuberculosis. An example of reasonably anticipated
contact between an employee and an individual with suspected or confirmed
infectious TB would be an admissions clerk working in a homeless shelter. In
view of the high incidence of TB among the homeless, it can reasonably be
anticipated that an employee screening people for admission into the shelter
would have contact with a person with infectious TB during the performance of
his or her job duties. Another, more obvious, example would be a
bronchoscopist in a hospital that provides care for individuals with
suspected or confirmed infectious TB. Others could include some physicians,
nurses, paramedics and emergency medical technicians, health aides, prison
guards, and intake workers in the facilities listed in paragraph (a) of this
section. An example of an employee who would not be reasonably anticipated to
have occupational exposure is an worker, in a covered facility, whose duties
were limited to working in an area where suspected or confirmed TB patients
or clients do not go and where the air would not contain aerosolized Mycobacterium
tuberculosis. The risk of exposure for this employee is comparable to the
exposure potential by the general population. The
term occupational exposure is used differently than the term exposure
incident in the proposed standard. Occupational exposure is used to
define a condition of the employee's work and to identify which employees are
affected in a way that can reasonably be anticipated, due to their job
duties, to involve potential exposure to aerosolized M. tuberculosis,
i.e., contact with an individual with suspected or confirmed infectious TB or
with air that may contain aerosolized M. tuberculosis. The intent of
the standard is to prevent exposure to aerosolized M. tuberculosis;
therefore, certain proactive measures are required by the standard, e.g.,
training and medical surveillance, when occupational exposure is present. In
order to provide these measures, it is necessary to identify which employees
may be exposed before exposure occurs. The definition of
"occupational exposure" is the basis for making this
identification. An
exposure incident, on the other hand, is a discrete event in which it
is known that an employee has had contact with aerosolized M. tuberculosis,
i.e., with an individual with confirmed infectious TB or air containing
aerosolized M. tuberculosis. The term "exposure incident" is
used to define those occasions when certain reactive measures are required by
the standard, such as medical management and follow-up. It is exposure to an
individual with confirmed infectious TB that matters, since it is not
necessary to take reactive measures after being exposed to an individual with
suspected infectious TB if that individual has subsequently been determined
not to have infectious TB. Physician or Other Licensed Health Care Professional means an individual whose legally
permitted scope of practice (i.e., license, registration, or certification)
allows her or him to independently perform or be delegated to perform some or
all of the health care services required by paragraph (g) of this section. Paragraph
(g) requires that all medical evaluations and procedures and medical
management and follow-up be performed by or under the supervision of a
physician or other licensed health care professional, as appropriate. OSHA is
aware that a variety of health care professionals are licensed by their
respective states to legally perform different medical provisions required
under this proposed standard. This definition clarifies that it is not OSHA's
intent to dictate the specific type of health care professional to perform
the activities required by the medical surveillance paragraph. OSHA's intent
is merely that these activities be performed by persons who are legally
permitted to independently perform or be delegated to perform some or all of
the health care services required under the medical surveillance provisions
of the standard. Employers wishing to use the services of a variety of health
care providers must be familiar with the licensing laws of their state to
ensure that the activities being performed are within the scope of that
health care provider's licensure. Powered air-purifying respirator (PAPR) means an air-purifying respirator
that uses a blower to deliver air through the air-purifying element to the
wearer's breathing zone. A PAPR uses a blower to draw ambient air through a
filter and provide this filtered air, under pressure, to the facepiece of the
wearer. Qualitative fit test means a pass/fail fit test to assess the adequacy of respirator fit
that relies on the respirator wearer's response. Generally, this assessment
of adequacy of respirator fit is made by determining whether an individual
wearing the respirator can detect the odor, taste, or irritation of a
challenge agent introduced into the vicinity of the wearer's breathing zone. Quantitative fit test means an assessment of the adequacy of respirator fit by numerically
measuring the amount of leakage into the respirator. Leakage can be assessed
through means such as measuring the concentration of a challenge agent (or
air pressure) outside of the respirator versus the concentration of the agent
(or air pressure) inside the respirator. The ratio of the two measurements is
an index of the leakage of the seal between the respirator facepiece and the
wearer's face. Research laboratory is defined as a laboratory that propagates and manipulates cultures
of M. tuberculosis in large volumes or high concentrations that are in
excess of those used for identification and typing activities common to
clinical laboratories. The purpose of this definition is to distinguish
research laboratories from clinical laboratories. Under paragraph (e) of the
proposed standard, research laboratories are required to meet additional
provisions beyond those required for clinical laboratories (e.g., use
of a hazard warning sign incorporating the biohazard symbol when materials
containing M. tuberculosis are present in the laboratory and use of
two sets of self-closing doors for entry into the work area from access
corridors). These additional requirements are proposed due to the higher
degree of hazard that may be present in research laboratories as a result of
the presence of research materials that may contain M. tuberculosis in
larger volumes and higher concentrations than would normally be found in
diagnostic specimens or cultures in clinical laboratories. Respirator
means a device worn by an individual and intended to provide the wearer with
respiratory protection against inhalation of airborne contaminants. While the
term "respirator" may be used in medical situations to refer to a
device that provides breathing assistance to an individual who is
experiencing breathing difficulty, this section utilizes this term only in
reference to the type of protective device defined above. Suspected infectious tuberculosis means a potential disease state in which an
individual is known, or with reasonable diligence should be known, by the
employer to have one or more of the following conditions, unless the
individual's condition has been medically determined to result from a cause
other than TB: (1) to be infected with M. tuberculosis and to have the
signs or symptoms of TB; (2) to have a positive acid-fast bacilli (AFB)
smear; or (3) to have a persistent cough lasting 3 or more weeks and two or
more symptoms of active TB (e.g., bloody sputum, night sweats, weight
loss, fever, anorexia). An individual with suspected infectious TB has
neither confirmed infectious TB nor has he or she been medically determined
to be noninfectious. Suspected infectious TB is another key term in the proposed standard. The presence of a person
with suspected infectious TB triggers and is associated with a number of the
provisions required of employers. Applying the criteria associated with
suspected infectious TB is the first step in the early identification of
individuals with infectious TB and is therefore a key factor in the
elimination and minimization of occupational transmission of TB. Therefore,
for purposes of implementing the standard it is important that what
constitutes "suspected infectious TB" is clear. The
first criterion in identifying an individual as having suspected infectious
TB is the presence of TB infection and the signs and symptoms of active TB. Under
the second criterion, an individual would be suspected of having infectious
TB if that individual had a positive AFB smear. The third criterion is based
primarily on observation of an individual. The CDC states that: *
* * A diagnosis of TB may be considered for any patient who has a persistent
cough (i.e., a cough lasting for ?
3 weeks) or other signs or symptoms compatible with active TB (e.g.,
bloody sputum, night sweats, weight loss, anorexia or fever). * * *
Diagnostic measures for identifying TB should be conducted for patients in
whom active TB is being considered. These measures include obtaining a
medical history and performing a physical examination, PPD skin test, chest
radiograph, and microscopic examination and culture of sputum or other
appropriate specimens. (Ex. 4B) OSHA
has relied on the CDC's list of symptoms, but does not agree that employers
need only "consider" a TB diagnosis when any of the symptoms
appear. The Agency believes that requiring employers merely to consider a TB
diagnosis under these circumstances may allow too many individuals with
infectious TB to slip through this screen and remain unidentified. In
addition, the CDC recommendations do not identify the minimum number of signs
or symptoms that should trigger employer concern. The problem with the CDC's
approach is that the signs and symptoms are so general that they would be
difficult to apply in many of the occupational exposure circumstances covered
by the standard. For example, if OSHA required employers to identify each
individual with even one of the signs or symptoms of TB as having suspected
infectious TB, too many individuals would be likely to be identified, thereby
wasting valuable health care resources. For these reasons, OSHA has proposed
that employers be required to determine that an individual has suspected
infectious TB when the individual has a prolonged cough and at least two of
the other signs or symptoms of infectious TB. The Agency believes that
requiring the employer to identify individuals as suspect cases when they
have only a prolonged cough, which is the primary mode of transmission, and
at least 2 other signs or symptoms strikes the appropriate balance between
over inclusion and under inclusion, i.e., between considering almost every
individual in poor health as a suspect case and missing individuals who
should be suspected of having infectious TB. OSHA believes that setting forth
these more definitive criteria will meet the needs of the many employers
covered by this standard who will not have skilled medical persons making
initial determinations about whether or not an individual has suspected
infectious TB. Employer who are in a position to make medical determinations
are permitted by the standard to rule out infectious TB by determining that a
given individual's signs and symptoms are the result of a cause other than
TB. That
an employer knows or with reasonable diligence should know that an individual
meets one or more of these criteria means that an employer must utilize the
means at his or her disposal to gather relevant information about the
individual. For example, the employer may have access to the medical records
of the individual or may question an individual who has signs or symptoms of
TB in order to obtain information about the individual, such as skin test
status, AFB smear status, and so forth. How much questioning the employer
might do depends on the work setting. For example, a hospital will have
intake procedures that include asking questions, as will most homeless
shelters and other fixed work sites. In other work settings, such as the many
places in which emergency medical services and home health care are provided
to unidentified individuals with infectious TB, the employer's obligation
will be to respond when an employee notices signs or symptoms compatible with
TB. In many of these instances, it is the training employees receive in
identifying individuals with suspected TB that will be the most important
factor. In
addition, as noted above, an individual who meets one or more of the above
criteria but whose condition has been medically determined to result from a
cause other than TB need not be considered to have suspected infectious TB. For
example, a physician or other licensed health care professional, as
appropriate, could determine that the signs and symptoms exhibited by the
individual were the result, for example, of pneumonia and not TB. Tight-fitting respirator means a respiratory inlet covering that is designed to form a
complete seal with the face. A half-facepiece covers the nose and mouth while
a full facepiece covers the nose, mouth, and eyes. Tuberculosis (TB) means a disease caused by M. tuberculosis. Tuberculosis infection means a condition in which living M. tuberculosis bacilli are
present in the body, without producing clinically active disease. Although
the infected individual has a positive tuberculin skin test reaction, the
individual may have no symptoms related to the infection and may not be
capable of transmitting the disease. Tuberculosis disease is a condition in which living M. tuberculosis bacilli are
present in the body, producing clinical illness. The individual may or may
not be infectious. Tuberculin skin test means a method used to evaluate the likelihood that a person is
infected with M. tuberculosis. The method utilizes an intradermal
injection of tuberculin antigen with subsequent measurement of reaction
induration. It is also referred to as a PPD skin test. Two-step testing is a baseline skin testing procedure used to differentiate between a
boosted skin test reaction and a skin test reaction that signifies a new
infection. If the initial skin test is negative, a second skin test is
administered 1 to 3 weeks later. If the second skin test is positive, the
reaction is probably due to boosting. If the second skin test is negative,
the individual is considered to be not infected. A subsequent positive skin
test in this individual would thus indicate a new infection. Boosting is
discussed in more detail in connection with the Medical Surveillance
paragraph. Paragraph (k) Dates As
proposed, the final rule would become effective ninety (90) days after
publication in the Federal Register. This will allow time for public
distribution and give employers time to familiarize themselves with the
standard. The various provisions have phased-in effective dates. The
employer's initial duty under the standard is the exposure determination and
establishment of the written Exposure Control Plan required by paragraph (c)
of this section. The plan would need to be completed 30 days after the
effective date. Thirty
days later, 60 days after the effective date, paragraphs (h)(3), Information
and Training, (g) Medical Surveillance, and (i) Recordkeeping would take
effect. Ninety
(90) days after the effective date, the work practice procedures and
engineering controls required by paragraph (d) (in work settings other than
those noted below), the respiratory protection required by paragraph (f), and
the labels and signs required by paragraphs (h) (1) and (2) would take
effect. The work practices that are directly related to the engineering
controls would have to be implemented as soon as the engineering controls
were functional. Finally, the requirements for clinical and research
laboratories contained in paragraph (e) would also take effect 90 days after
the effective date. For
businesses with fewer than 20 employees, the engineering controls required by
paragraph (d) of this section would take effect 270 days after the effective
date. As noted above, the work practices directly related to the engineering
controls being installed in accordance with paragraph (d) of this section
must be implemented as soon as the engineering controls are implemented. Since
engineering controls may necessitate more extensive planning than is required
to comply with other provisions of the standard, OSHA is proposing an extended
phase-in for the smallest employers. Since
many employers have many of these provisions already in effect through
current infection control plans, OSHA believes that these dates provide
adequate time for compliance. Nevertheless, OSHA seeks comment on the
appropriateness of the dates for compliance with the various provisions of
the standard. XI. Public Participation -- Notice of Hearing Interested
persons are invited to submit written data, views, and arguments with respect
to this proposed standard. These comments must be postmarked on or before
December 16, 1997, and submitted in quadruplicate to the Docket Officer,
Docket No. H-371, Room N2625, U.S. Department of Labor, 200 Constitution
Avenue NW., Washington, DC 20210. Comments limited to 10 pages or less also
may be transmitted by facsimile to (202) 219-5046, provided the original and
three copies are sent to the Docket Officer thereafter. Written
submissions must clearly identify the provisions of the proposal that are
being addressed and the position taken with respect to each issue. The data,
views, and arguments that are submitted will be available for public
inspection and copying at the above address. All timely written submissions
will be made a part of the record of the proceeding. Pursuant
to section 6(b)(3) of the Act, an opportunity to submit oral testimony
concerning the issues raised by the proposed standard will be provided at an
informal public hearing scheduled to begin at 10:00 A.M. on February 3, 1998,
in Washington, DC in the Auditorium of the Frances Perkins Building, U.S.
Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210. Notice of Intention to Appear All
persons desiring to participate at the hearings must file in quadruplicate a
notice of intention to appear postmarked on or before December 16, 1997
addressed to the Docket Officer, Docket No. H-371, Room N-2625, U.S.
Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210;
telephone (202) 219-7894. The Notice of Intention to Appear also may be
transmitted by facsimile to (202) 219-5046, provided the original and 3
copies of the notice are sent to the above address thereafter. The
Notices of Intention to Appear, which will be available for inspection and
copying at the OSHA Docket Office, must contain the following information: (1)
The name, address, and telephone number of each person to appear; (2)
The hearing site that the party is requesting to attend; (3)
The capacity in which the person will appear; (4)
The approximate amount of time requested for the presentation; (5)
The specific issues that will be addressed; (6)
A detailed statement of the position that will be taken with respect to each
issue addressed; (7)
Whether the party intends to submit documentary evidence, and if so, a brief
summary of that evidence; and (8)
Whether the party wishes to testify on the days set aside to focus on
homeless shelters. Filing of Testimony and Evidence Before Hearings Any
party requesting more than 10 minutes for a presentation at the hearing, or
who will submit documentary evidence, must provide in quadruplicate the
complete text of the testimony, including any documentary evidence to be
presented at the hearing to the Docket Officer at the above address. This
material must be postmarked by December 31, 1997 and will be available for
inspection and copying at the OSHA Docket Office. Each such submission will
be reviewed in light of the amount of time requested in the Notice of
Intention to Appear. In those instances where the information contained in the
submission does not justify the amount of time requested, a more appropriate
amount of time will be allocated and the participant will be notified of that
fact. Any
party who has not substantially complied with this requirement may be limited
to a 10-minute presentation. Any party who has not filed a Notice of
Intention to Appear may be allowed to testify, as time permits, at the
discretion of the Administrative Law Judge. OSHA
emphasizes that the hearing is open to the public, and that interested
persons are welcome to attend. However, only persons who have filed proper
notices of intention to appear will be entitled to ask questions and
otherwise participate fully in the proceeding. Conduct and Nature of Hearings The
hearings will commence at 10:00 a.m. on February 3, 1998. At that time any
procedural matters relating to the proceeding will be resolved. The
nature of an informal hearing is established in the legislative history of
section 6 of the Act and is reflected by the OSHA hearing regulations (see 29
CFR 1911.15 (a)). Although the presiding officer is an Administrative Law
Judge and questioning by interested persons is allowed on crucial issues, the
proceeding shall remain informal and legislative in type. The essential
intent is to provide an opportunity for effective oral presentations that can
proceed expeditiously in the absence of rigid procedures that would impede or
protract the rulemaking process. Additionally,
since the hearing is primarily for information gathering and clarification,
it is an informal administrative proceeding, rather than an adjudicative one.
The technical rules of evidence, for example, do not apply. The regulations
that govern hearings and the pre-hearing guidelines to be issued for this
hearing will ensure fairness and due process and also facilitate the
development of a clear, accurate and complete record. Those rules and
guidelines will be interpreted in a manner that furthers that development. Thus,
questions of relevance, procedure and participation generally will be decided
so as to favor development of the record. The
hearing will be conducted in accordance with 29 CFR Part 1911. The hearing
will be presided over by an Administrative Law Judge who makes no
recommendation on the merits of OSHA's proposal. The responsibility of the
Administrative Law Judge is to ensure that the hearing proceeds at a
reasonable pace and in an orderly manner. The Administrative Law Judge,
therefore, will have all the powers necessary and appropriate to conduct a
full and fair informal hearing as provided in 29 CFR Part 1911 and the
prehearing guidelines, including the powers: (1)
To regulate the course of the proceedings; (2)
To dispose of procedural requests, objections, and comparable matters; (3)
To confine the presentation to the matters pertinent to the issues raised; (4)
To regulate the conduct of those present at the hearing by appropriate means; (5)
At the Judge's discretion, to question and permit the questioning of any
witness and to limit the time for questioning; and (6)
At the Judges's discretion, to keep the record open for a reasonable, stated
time to written information and additional data, views and arguments from any
person who has participated in the oral proceeding. Information on Homeless Shelter Issues for the Public Hearing OSHA
seeks to gather additional information related to homeless shelters during
the written comment period and the public hearing. OSHA recognizes the unique
service provided by homeless shelters, yet is also aware that shelters serve
a client population that has been identified as possessing a high prevalence
of active TB. OSHA is seeking information on all aspects of TB and employee
protection against occupational transmission of TB in homeless shelters (e.g.,
means successfully being used by shelters to achieve early identification of
shelter clients with suspected or confirmed infectious TB; successful
programs currently being used to protect employees against occupational
transmission of TB). The
Agency intends to designate a special session during the Washington, D.C.
hearing to focus on the issues surrounding homeless shelters. We encourage
hearing participants whose primary testimony will involve homeless shelters
to indicate this in their Notice of Intention to Appear; OSHA will attempt to
schedule these participants on the day(s) of the hearing set aside to focus
on homeless shelters. Other participants whose testimony will not be
primarily on homeless shelter issues but who wish to address the topic of
homeless shelters will be scheduled another day, but they may enter a
separate statement in the record during this period. In any case,
participants are free to discuss homeless shelters or any other issue related
to this proposed standard whenever they present their testimony. Certification of Record and Final Determination After Hearing Following
the close of the posthearing comment period, the presiding Administrative Law
Judge will certify the record to the Assistant Secretary of Labor for
Occupational Safety and Health. The Administrative Law Judge does not make or
recommend any decisions as to the content of the final standard. The
proposed standard will be reviewed in light of all testimony and written
submissions received as part of the record, and a standard will be issued
based on the entire record of the proceeding, including the written comments
and data received from the public. List of Subjects Health
professionals, Occupational safety and health, Reporting and recordkeeping
requirements, Tuberculosis. XII. Authority and Signature This
document was prepared under the direction of Greg Watchman, Acting Assistant
Secretary of Labor, 200 Constitution Avenue, N.W., Washington, D.C., 20210. It
is issued under sections 4, 6, and 8 of the Occupational Safety and Health
Act of 1970 (29 U.S.C. 653, 655, 657), Secretary of Labor's Order 1-90 (55 FR
9033) and 29 CFR Part 1911. Signed
at Washington, DC, this 15th day of September, 1997. Greg Watchman, XIII. The Proposed
Standard Part
1910 of Title 29 of the Code of Federal Regulations is proposed to be amended
as follows: PART 1910 -- [AMENDED] Subpart Z -- [Amended] 1.
The general authority citation for Subpart Z of 29 CFR Part 1910 continues to
read as follows and a new citation for § 1910.1035 is added: Authority:
Secs. 6 and 8, Occupational Safety and Health Act, 29 U.S.C. 655, 657,
Secretary of Labor's Orders Nos. 12-71 (36 FR 8754), 8-76 (41 FR 25059), or
9-83 (48 FR 35736), as applicable; and 29 CFR Part 1911. *
* * * * Section
1910.1035 also issued under 29 U.S.C. 653. *
* * * * 2.
Section 1910.1035 is added to read as follows: 1910.1035 Tuberculosis (1)
In hospitals; (2)
In long term care facilities for the elderly; (3)
In correctional facilities and other facilities that house inmates or
detainees; (4)
In hospices; (5)
In shelters for the homeless; (6)
In facilities that offer treatment for drug abuse; (7)
In facilities where high-hazard procedures (as defined by this section) are
performed; (8)
In laboratories that handle specimens that may contain M. tuberculosis,
or process or maintain the resulting cultures, or perform related activity
that may result in the aerosolization of M. tuberculosis; Note to paragraph (a)(8): Occupational exposure incurred in any of the work settings listed in
paragraphs (a)(1) through (a)(8) of this section by temporary or contract
employees or by personnel who service or repair air systems or equipment or who
renovate, repair, or maintain areas of buildings that may reasonably be
anticipated to contain aerosolized M. tuberculosis is covered by this
section. (9)
During the provision of social work, social welfare services, teaching, law
enforcement or legal services if the services are provided in any of the work
settings listed in paragraphs (a)(1) through (a)(8) of this section, or in
residences, to individuals who are in AFB isolation or are segregated or
otherwise confined due to having suspected or confirmed infectious TB. (10)
During the provision of emergency medical services, home health care and
home-based hospice care. (b) Application. An employer covered under paragraph (a) of this section, Scope
(other than the operator of a laboratory), may choose to comply only with the
provisions of appendix A to this section if the Exposure Control Plan
demonstrates that his or her facility or work setting: (1) Does not admit or
provide medical services to individuals with suspected or confirmed
infectious TB; and (2)
Has had no case of confirmed infectious TB in the past 12 months; and (3)
Is located in a county that, in the past 2 years, has had 0 cases of
confirmed infectious TB reported in one year and fewer than 6 cases of
confirmed infectious TB reported in the other year. (c)
Exposure control -- (1)
Exposure determination. (i) Each employer who has any employee with occupational exposure
shall prepare an exposure determination that contains the following: (A)
A list of the job classifications in which all employees have occupational
exposure; and (B)
A list of the job classifications in which some employees have occupational
exposure, and a list of all tasks and procedures (or groups of closely
related tasks and procedures) that these employees perform and that involve
occupational exposure. (ii)
The exposure determination shall be made without regard to the use of
respiratory protection. (2)
Exposure Control Plan. (i) Each employer who has any employee with
occupational exposure shall establish a written Exposure Control Plan that
must include: (A)
The exposure determination required by paragraph (c)(1) of this section; (B)
Procedures for providing information about individuals with suspected or
confirmed infectious TB or about air that may reasonably be anticipated to
contain aerosolized M. tuberculosis to occupationally exposed
employees who need this information in order to take proper precautions; and (C)
Procedures for reporting an exposure incident, including procedures
specifying the individual to whom the incident is to be reported, and
procedures for evaluating the circumstances surrounding the exposure
incident. (ii)
Each employer who transfers individuals with suspected or confirmed
infectious TB to a facility with AFB isolation capabilities shall include in
the Exposure Control Plan procedures for prompt identification, masking or
segregation, and transfer of such individuals. Note to paragraph (c)(2)(ii): An employer's duties regarding transfer
will vary with the type of facility the employer operates and the work
performed by his or her employees. For example, the transfer responsibilities
of hospitals, long-term care facilities for the elderly, correctional
facilities, and hospices may include contacting the receiving facility,
providing transport, and taking other steps to ensure that the individual
with suspected or confirmed infectious TB reaches the receiving facility. By
contrast, the responsibilities of facilities that do not maintain custody
over individuals, such as homeless shelters or facilities that offer
treatment for drug abuse, might only include providing information about the
receiving facility, contacting the facility, and providing directions to the
facility. (iii)
Each employer in whose facility individuals with suspected or confirmed
infectious TB are admitted or provided medical services shall include each of
the following provisions in the Exposure Control Plan: (A)
Procedures for prompt identification of individuals with suspected or
confirmed infectious TB; (B)
Procedures for isolating and managing the care of individuals with suspected
or confirmed infectious TB, including: (1)
Minimizing the time an individual with suspected or confirmed infectious TB
remains outside of an AFB isolation room or area (e.g., in an
emergency room); (2)
Minimizing employee exposure in AFB isolation rooms or areas by combining
tasks to limit the number of entries into the room or area and by minimizing
the number of employees who must enter and minimizing the time they spend in
the room or area; (3)
Delaying elective transport or relocation within the facility of an
individual with suspected or confirmed infectious TB. Procedures are to be
established to assure that, to the extent feasible, services and procedures
for individuals with suspected or confirmed infectious TB are brought into or
conducted in an AFB isolation room or area; (4)
Using properly-fitted masks (e.g., surgical masks, valveless
respirators) on individuals with suspected or confirmed infectious TB or
transporting such individuals in portable containment engineering controls
when relocation or transport outside of AFB isolation rooms or areas is
unavoidable. Procedures are to be established to assure that the individual
is returned to an AFB isolation room or area as soon as is practical after
completion of the service or procedure; (5)
Delaying elective high-hazard procedures or surgery until an individual with
suspected or confirmed infectious TB is determined to be noninfectious; (C)
A list of all high-hazard procedures, if any, performed in the work setting;
and (D)
A schedule for inspection, maintenance, and performance monitoring of
engineering controls (see appendix E to this section). (iv)
Each employer who operates a laboratory shall include in the Exposure Control
Plan a determination from the director of the laboratory as to whether the
facility should operate at Biosafety Level 2 or 3 containment according to
current CDC recommendations (CDC/NIH Biosafety in Microbiological and
Biomedical Laboratories). The laboratory director shall determine and
document the need for: (A)
Controlled access; (B)
Anterooms; (C)
Sealed windows; (D)
Directional airflow; (E)
Measures to prevent recirculation of laboratory exhaust air; (F)
Filtration of exhaust air before discharge outside; and (G)
Thimble exhaust connections for biological safety cabinets. (v)
Each employer who provides home health care or home-based care shall include
in the Exposure Control Plan procedures for prompt identification of
individuals with suspected or confirmed infectious TB and procedures for
minimizing employee exposure to such individuals; a list of the high-hazard
procedures, if any, performed in the work setting; and procedures for
delaying elective high-hazard procedures or surgery until the individual is
noninfectious. (vi)
Each employer who claims reduced responsibilities related to paragraph (b),
Application, or paragraph (g)(3)(iii)(D), Medical Surveillance, of this
section shall document in the Exposure Control Plan the number of individuals
with confirmed infectious tuberculosis encountered in the work setting in the
past 12 months. (vii)
The Exposure Control Plan shall be: (A)
Accessible to employees in accordance with 29 CFR 1910.20(e); (B)
Reviewed at least annually and updated whenever necessary to reflect new or
modified tasks, procedures, or engineering controls that affect occupational
exposure and to reflect new or revised employee job classifications with
occupational exposure; and (C)
Made available for examination and copying to the Assistant Secretary and/or
the Director upon request. (d) Work Practices and Engineering Controls. (1) Work practices and
engineering controls shall be used to eliminate or minimize employee
exposures to M. tuberculosis. (2)
The work practices in the Exposure Control Plan shall be implemented. (3)
Individuals with suspected or confirmed infectious TB shall be identified,
and except in settings where home health care or home-based hospice care is
being provided, shall be: (i)
Masked or segregated in such a manner that contact with employees who are not
wearing respiratory protection is eliminated or minimized until transfer or
placement in an AFB isolation room or area can be accomplished; and (ii)
Placed in an AFB isolation room or area or transferred to a facility with AFB
isolation rooms or areas within 5 hours from the time of identification, or
temporarily placed in AFB isolation within 5 hours until placement or
transfer can be accomplished as soon as possible thereafter. (4)
High-hazard procedures shall be conducted in an AFB isolation room or area. (5)
Engineering controls shall be used in facilities that admit or provide
medical services or AFB isolation to individuals with suspected or confirmed
infectious TB except in settings where home health care or home-based hospice
care is being provided. (i)
Negative pressure shall be maintained in AFB isolation rooms or areas. (ii)
Negative pressure shall be qualitatively demonstrated (e.g., by smoke
trails) daily while a room or area is in use for TB isolation (see appendix G
to this section). (iii)
Engineering controls shall be maintained, and inspected and performance
monitored for filter loading and leakage every 6 months, whenever filters are
changed, and more often if necessary to maintain effectiveness (see appendix
E to this section). (iv)
Air from AFB isolation rooms or areas shall be exhausted directly outside,
away from intake vents, employees, and the general public. Air that cannot be
exhausted in such a manner or must be recirculated must pass through HEPA
filters before discharge or recirculation. (v)
Ducts carrying air that may reasonably be anticipated to contain aerosolized M.
tuberculosis shall be maintained under negative pressure for their entire
length before in-duct HEPA filtration or until the ducts exit the building
for discharge. (vi)
Doors and windows of AFB isolation rooms or areas shall be kept closed while
in use for TB isolation, except when doors are opened for entering or exiting
and when windows are part of the ventilation system being used to achieve
negative pressure. (vii)
When an AFB isolation room or area is vacated by an individual with suspected
or confirmed infectious TB, the room or area shall be ventilated according to
current CDC recommendations for a removal efficiency of 99.9 % before
permitting employees to enter without respiratory protection (see appendix C
to this section). (6)
The employer shall provide information about the TB hazard to any contractor
who provides temporary or contract employees who may incur occupational
exposure so that the contractor can institute precautions to protect his or
her employees. (e) Clinical and Research Laboratories. (1) This paragraph applies to clinical and
research laboratories that engage in the culture, production, concentration,
experimentation, or manipulation of M. tuberculosis. The requirements
in this paragraph apply in addition to the other requirements of the
standard. (2)
Clinical and research laboratories shall meet the following criteria: (i)
Standard microbiological practices. (A)
Procedures shall be performed in a manner that minimizes the creation of
aerosols. (B)
Mouth pipetting shall be prohibited. (C)
Work surfaces and laboratory equipment shall be decontaminated at the end of
each shift and after any spill of viable material. (D)
Cultures, stocks and other wastes contaminated with M. tuberculosis
shall be decontaminated before disposal by a decontamination method, such as
autoclaving, known to effectively destroy M. tuberculosis. Materials
to be decontaminated outside of the immediate laboratory shall be placed in a
durable, leakproof container, closed and sealed for transport from the
laboratory and labeled or color-coded in accordance with paragraph (h)(1)(ii)
of this section. (ii)
Special practices. (A) Access to the laboratory shall be limited by the
laboratory director when work with M. tuberculosis is in progress. (B)
A biosafety manual that includes procedures for spill management shall be
adopted. The employer shall review the manual as necessary and at least
annually. The employer shall update the biosafety manual as necessary to
reflect changes in the work setting. Employees shall be advised of potential
hazards, shall be required to read instructions on practices and procedures,
and shall be required to follow them. (C)
Cultures, tissues, or specimens of body fluids contaminated with M.
tuberculosis shall be placed in a container that prevents leakage during
collection, handling, processing, storage, transport, or shipping. (D)
All spills shall be immediately contained and cleaned up by employees who are
properly trained and equipped to work with potentially concentrated M.
tuberculosis. A spill or accident that results in an exposure incident
shall be reported immediately to the laboratory director or other designated
person. (E)
When materials containing or animals infected with M. tuberculosis are
present in the laboratory or containment module, a hazard warning sign, in
accordance with paragraph (h)(2)(iv), incorporating the universal biohazard
symbol, shall be posted on all laboratory and animal room access doors. (iii)
Containment equipment. (A) Certified biological safety cabinets (Class
2) shall be used whenever procedures with a potential for generating aerosols
of M. tuberculosis are conducted or whenever high concentrations or
large volumes of M. tuberculosis are used. Such materials may be
centrifuged in the open laboratory if sealed rotor heads or centrifuge safety
cups are used, and if these rotors or safety cups are opened in a biological
safety cabinet. (B)
Biological safety cabinets shall be certified when installed, annually
thereafter, whenever they are moved, and whenever filters are changed. (iv)
Laboratory facilities. A method for decontamination of wastes contaminated
with M. tuberculosis (e.g., autoclave, chemical disinfection,
incinerator, or other decontamination system known to effectively destroy M.
tuberculosis) shall be available within or as near as feasible to the
work area. (3)
Research laboratories shall meet the following additional criteria: (i)
Special practices. (A) Laboratory doors shall be kept closed when work
involving M. tuberculosis is in progress. (B)
Access to the work area shall be limited to authorized persons. Written
policies and procedures shall be established so that only persons who have
been advised of the potential biohazard, who meet any specific entry
requirements, and who comply with all entry and exit procedures shall be
allowed to enter the work areas and animal rooms. (C)
Respiratory protection shall be worn when aerosols cannot be safely contained
(e.g., when aerosols are generated outside of a biological safety
cabinet). (ii)
Containment equipment. Certified biological safety cabinets (Class 2 or
3) or appropriate combinations of personal protection or physical containment
devices, such as respirators, centrifuge safety cups, sealed centrifuge
rotors, and containment caging for animals, shall be used for manipulations
of cultures and those clinical or environmental materials that may be a
source of aerosols containing M. tuberculosis; aerosol challenge of
animals with M. tuberculosis; harvesting of tissues or fluids from
animals infected with M. tuberculosis; or the necropsy of animals
infected with M. tuberculosis. (iii)
Laboratory facilities. (A) The laboratory shall be separated from
areas that are open to unrestricted traffic flow within the building. Passage
through two sets of self-closing doors shall be required for entry into the
work area from access corridors or other contiguous areas. (B)
Windows in the laboratory shall be closed and sealed. (C)
A ducted exhaust air ventilation system shall be provided. This system shall
create directional airflow that draws air from "clean" areas into
the laboratory toward "contaminated" areas. The employer shall
verify the proper direction of the airflow (i.e., into the work area) at
least every six months. The exhaust air shall not be recirculated to any
other area of the building, shall be discharged to the outside, and shall be
dispersed away from occupied areas and air intakes. (D)
The high efficiency particulate air (HEPA)-filtered exhaust air from Class 2
or Class 3 biological safety cabinets shall be discharged directly to the
outside or through the building exhaust system. If the HEPA-filtered exhaust
air from Class 2 or 3 biological safety cabinets is to be discharged to the
outside through the building exhaust air system, it shall be connected to
this system in a manner (e.g., thimble units) that avoids any
interference with the air balance of the cabinets or building exhaust system. (E)
Continuous flow centrifuges or other equipment that may produce aerosols
shall be contained in devices that exhaust air through HEPA filters before
discharge into the laboratory. (f) Respiratory Protection -- (1) General. (i) Each employer shall
provide a respirator to each employee who: (A)
Enters an AFB isolation room or area in use for TB isolation; (B)
Is present during the performance of procedures or services for an individual
with suspected or confirmed infectious TB who is not masked; (C)
Transports an individual with suspected or confirmed infectious TB in an
enclosed vehicle (e.g., ambulance, helicopter) or who transports an
individual with suspected or confirmed infectious TB within the facility when
that individual is not masked; (D)
Repairs, replaces, or maintains air systems or equipment that may reasonably
be anticipated to contain aerosolized M. tuberculosis; (E)
Is working in an area where an unmasked individual with suspected or
confirmed infectious TB has been segregated or otherwise confined (e.g.,
while awaiting transfer); or (F)
Is working in a residence where an individual with suspected or confirmed
infectious TB is known to be present. (ii)
Each employer who operates a research laboratory shall provide a respirator to
each employee who is present when aerosols of M. tuberculosis cannot
be safely contained (e.g., when aerosols are generated outside of a
biological safety cabinet). (iii)
The employer shall provide the respirator at no cost to the employee and
shall assure that the employee uses the respirator in accordance with the
requirements of this section. (iv)
The employer shall assure that the employee dons the respirator before
entering any of the work settings or performing any of the tasks set forth in
paragraphs (f)(1)(i) and (f)(1)(ii) of this section and uses it until leaving
the work setting or completing the task, regardless of other control measures
in place. (2)
Respiratory Protection Program. (i) Each employer who has any employer
whose occupational exposure is based on entering any of the work settings or
performing any of the tasks described in paragraph (f)(1) of this section
shall establish and implement a written respiratory protection program that
assures respirators are properly selected, fitted, used, and maintained. The
program shall include the following elements: (A)
Procedures for selecting the appropriate respirators for use in the work
setting; (B)
A determination of each employee's ability to wear a respirator, as required
under paragraph (g)(3)(ii) of this section, Medical Surveillance, for each
employee required to wear a respirator; (C)
Procedures for the proper use of respirators; (D)
Fit testing procedures for tight-fitting respirators; (E)
Procedures and schedules for cleaning, disinfecting, storing, inspecting,
repairing, or otherwise maintaining respirators; (F)
Training of employees to assure the proper use and maintenance of the
respirator, as required under paragraph (h) of this section, Communication of
Hazards and Training; and (G)
Procedures for periodically evaluating the effectiveness of the program. (ii)
The employer shall designate a person qualified by appropriate training or
experience to be responsible for the administration of the respiratory
protection program and for conducting the periodic evaluations of its
effectiveness. (iii)
The employer shall review and update the written program as necessary to
reflect current workplace conditions and respirator use. (iv)
The employer shall, upon request, make the written respiratory protection
program available to affected employees, their designated representatives,
the Assistant Secretary, and the Director. A copy of the program shall be
submitted to the Assistant Secretary and/or the Director, if requested. (3)
Respirator Selection. (i) The employer shall select and provide
properly fitted negative pressure or more protective respirators. Negative
pressure respirators shall be capable of being: (A)
Qualitatively or quantitatively fit tested in a reliable way to verify a
face-seal leakage of no more than 10 %; and (B)
Fit checked by the employee each time the respirator is donned. (ii)
The employer shall select a respirator that will function effectively in the
conditions of the work setting. In addition to meeting the criteria in paragraph
(f)(3)(i) of this section, the respirator shall be, at a minimum, either a
HEPA respirator selected from among those jointly approved as acceptable by
the Mine Safety and Health Administration and by the National Institute for
Occupational Safety and Health (NIOSH) under the provisions of 30 CFR part
11, or an N95 respirator certified by NIOSH under the provisions of 42 CFR
part 84. (4)
Respirator Use. (i) The employer shall not permit any respirator that
depends on a tight face-to-facepiece seal for effectiveness to be worn by
employees having any condition that prevents such a seal. Examples of these
conditions include, but are not limited to, facial hair that comes between
the sealing surface of the facepiece and the face or if facial hair interferes
with valve function, absence of normally worn dentures, facial scars, or
headgear that projects under the facepiece seal. (ii)
The employer shall assure that each employee who wears corrective glasses or
goggles wears them in a manner that does not interfere with the seal of the
facepiece to the face of the wearer. (iii)
Disposable respirators shall be discarded when excessive resistance, physical
damage, or any other condition renders the respirator unsuitable for use. (iv)
The employer shall assure that each employee, upon donning a tight-fitting
respirator, performs a facepiece fit check prior to entering a work area
where respirators are required. The procedures in appendix B to this section
or other procedures recommended by the respirator manufacturer that provide
protection equivalent to that provided by the procedures in appendix B shall
be used. (v)
Respirators shall be immediately repaired, or discarded and replaced, when
they are no longer in proper working condition. (vi)
The employer shall permit each employee to leave the respirator use area as
soon as practical to: (A)
Change the filter elements or replace the respirator whenever the ability of
the respirator to function effectively is compromised or the employee detects
a change in breathing resistance; or (B)
Wash his or her face and respirator facepiece as necessary to prevent skin
irritation associated with respirator use. (vii)
Each employee required to wear a respirator under this section shall be
evaluated in accordance with paragraph (g), Medical Surveillance, of this
section. (viii)
No employee shall be assigned a task requiring the use of a respirator if,
based upon the employee's most recent evaluation, the physician or other
licensed health care professional, as appropriate, determines that the
employee will be unable to function adequately while wearing a respirator. If
the physician or other licensed health care professional, as appropriate,
determines that the employee's job activities must be limited, or that the
employee must be removed from the employee's current job because of the
employee's inability to wear a respirator, the limitation or removal shall be
performed in accordance with paragraph (g)(5)(iii) of this section. (5)
Fit Testing. (i) The employer shall perform either quantitative or
qualitative face fit tests in accordance with the procedures outlined in
appendix B to this section. (ii)
The employer shall assure that each employee who must wear a tight-fitting
respirator passes a fit test: (A)
At the time of initial fitting; (B)
Whenever changes occur in the employee's facial characteristics which affect
the fit of the respirator; (C)
Whenever a different size or make of respirator is used; and (D)
At least annually thereafter unless the annual determination required under
paragraph (g)(3)(ii)(A), Medical Surveillance, of this section indicates that
the annual fit test is not necessary. (iii)
When quantitative fit testing is performed, the employer shall not permit an
employee to wear a tight-fitting half-mask respirator unless a minimum fit
factor of one hundred (100) is obtained in the test chamber. (6)
Maintenance and care of reusable and powered air purifying respirators.
(i) Respirators shall be cleaned and disinfected using the cleaning
procedures recommended by the manufacturer at the following intervals: (A)
As necessary for respirators issued for the exclusive use of an employee; and (B)
After each use for respirators issued to more than one employee. (ii)
Respirators shall be inspected before each use and during cleaning after each
use; (iii)
Respirator inspections shall include: (A)
A check of respirator function, tightness of connections and the condition of
the facepiece, head straps, valves, connecting tube, and cartridges,
canisters, or filters; and (B)
A check of the rubber or elastomer parts for pliability and signs of
deterioration. (iv)
Respirators that fail to pass inspection shall be removed from service and
shall be repaired or adjusted in accordance with the following: (A)
Repairs or adjustments to respirators are only to be made with NIOSH-approved
parts designed for the respirator by the respirator manufacturer, and
conducted by persons appropriately trained to perform such operations; (B)
Only repairs of the type and extent covered by the manufacturer's
recommendations may be performed; and (C)
Reducing or admission valves or regulators shall be returned to the
manufacturer or given to an appropriately trained technician for adjustment
or repair. (v)
Respirators shall be stored in a manner that protects them from
contamination, damage, dust, sunlight, extreme temperatures, excessive
moisture, and damaging chemicals and prevents deformation of the facepiece or
exhalation valve. (7)
Identification of filters, cartridges, and canisters. (i) Filters, cartridges,
and canisters used in the workplace shall be properly labeled and color-coded
with the NIOSH approval label as required by 30 CFR part 11 or 42 CFR part
84, whichever is applicable, before they are placed into service. (ii)
The NIOSH approval label on a filter, cartridge, or canister shall not be
intentionally removed, obscured, or defaced while it is in service in the
workplace. (8)
Respiratory protection program evaluation. The employer shall review
the overall respiratory protection program at least annually, and shall
conduct inspections of the workplace as necessary to assure that the
provisions of the program are being properly implemented for all affected
employees. The review of the program shall include an assessment of each
element required under paragraph (f)(2) of this section. (g)
Medical Surveillance -- (1) General. (i) Each employer who has
any employee with occupational exposure shall provide the employee with
medical surveillance as described in this paragraph. (ii)
Each employer covered under paragraph (a), Scope, of this section
shall provide information about the signs and symptoms of pulmonary TB, a
medical history, a physical examination, TB skin testing, medical management
and follow-up and, if indicated, other related tests and procedures, and
medical removal protection if the employee develops infectious TB, to any of
his or her employees who have an exposure incident while working in a covered
work setting, even if such employee is not categorized as having occupational
exposure. (iii)
Medical surveillance provisions, including examinations, evaluations,
determinations, procedures, and medical management and follow-up, shall be: (A)
Provided at no cost to the employee; (B)
Provided at a reasonable time and place for the employee; (C)
Performed by or under the supervision of a physician or other licensed health
care professional, as appropriate; and (D)
Provided according to recommendations of CDC current at the time these
evaluations and procedures take place, except as specified by this paragraph
(g). (iv)
Laboratory tests shall be conducted by an accredited laboratory. (2)
Explanation of Terms. This paragraph explains the terms used in
paragraph (g). (i)
Medical history emphasizes the pulmonary system, and includes previous
exposure to M. tuberculosis, BCG vaccination, TB skin test results, TB
disease, prior and current preventive or therapeutic treatment, current signs
or symptoms of active TB disease, and factors affecting immunocompetence; (ii)
Physical examination emphasizes the pulmonary system, signs and
symptoms of active TB disease, and factors affecting immunocompetence; (iii)
TB skin testing, includes anergy testing if indicated, and is only for
employees whose TB skin test status is not known to be positive. An initial
2-step protocol is to be used for each employee who has not been previously
skin tested and/or for whom a negative test cannot be documented within the
past 12 months. If the employer has documentation that the employee has had a
negative TB skin test within the past 12 months, that test may be utilized to
fulfill the skin testing portion of this requirement. Periodic retesting
shall be performed in accordance with paragraph (g)(3) of this section. (iv)
"Determination of the employee's ability to wear a respirator" is a
face-to-face assessment of the health factors affecting respirator use and
the need for the annual fit test. Note to paragraph (g)(2)(iv): A determination of the need for the annual
fit test may only be performed after the required initial fit test of the
employee and cannot be used in lieu of any other required fit tests, for
example, when a different size or make of respirator is used. (v)
"Medical management and follow-up" include diagnosis, and, where
appropriate, prophylaxis and treatment related to TB infection and disease. (vi)
Other related tests and procedures include those associated with TB
infection and disease and determined to be necessary by the physician or
other licensed health care professional, as appropriate. (vii)
Medical Removal Protection is the maintenance of earnings, seniority and
other benefits specified in paragraph (g)(5) of this section for an employee
who has confirmed or suspected infectious TB or is unable to wear a
respirator. (3)
Application. (i) Each employee with occupational exposure shall be
provided with the following at the times specified: (A)
Before initial assignment to a job with occupational exposure or within 60
days of the effective date of this standard and at least annually thereafter:
A medical history and TB skin testing, and, if indicated, a physical
examination and other related tests and procedures; Note to paragraph (g)(3)(i)(A): If an employee has had a medical
examination within the twelve (12) months preceding the effective date of the
standard and the employer has the documented results of that examination,
only the medical surveillance provisions required by the standard that were
not included in the examination need to be provided. The date(s) of the
previous medical examination and skin test shall be used to determine the
date(s) of the employee's next medical examination and skin test but in no
case shall the interval between the previous examination and skin test and
the next examination and skin test exceed 12 months. (B)
When the employee has signs or symptoms of TB, either observed or
self-reported: A medical history, a physical examination, TB skin testing,
medical management and follow-up, and, if indicated, other related tests and
procedures; (C)
When an employee undergoes an exposure incident: A medical history, TB skin
testing as soon as feasible (unless there is documented negative TB skin
testing within the past 3 months), and if the result is negative, another
skin test 3 months later, medical management and follow-up and, if indicated,
a physical examination and other related tests and procedures; (D)
When the employee has a TB skin test conversion: A medical history, a
physical examination, medical management and follow-up, and, if indicated,
other related tests; (E)
Within 30 days of the termination of employment: A TB skin test; and (F)
At any other time the physician or other licensed health care professional,
as appropriate, deems it necessary: Any or all the provisions of paragraph
(g). (ii)
Each employee who must wear a respirator shall be provided with the following
at the times specified: (A)
Before initial assignment to a job with occupational exposure or within 60
days of the effective date of this standard and at least annually thereafter:
A determination of the employee's ability to wear a respirator; and (B)
When the wearer experiences unusual difficulty while being fitted or while
using a respirator: A determination of the employee's ability to wear a
respirator, including relevant components of a medical history, and, if
indicated, a physical examination and other related tests and procedures. (iii)
An employee with negative TB skin test status shall be provided with a TB
skin test every 6 months if the employee in the course of his or her duties: (A)
Enters an AFB isolation room or area; (B)
Performs or is present during the performance of high-hazard procedures; (C)
Transports or is present during the transport of an individual with suspected
or confirmed infectious TB in an enclosed vehicle; or (D)
Works in an intake area where early identification procedures are performed (e.g.,
emergency departments, admitting areas) in facilities where six (6) or more
individuals with confirmed infectious TB have been encountered in the past
twelve months. (4)
Additional Requirements. (i) The employer shall assure that when the
physician or other licensed health care professional, as appropriate,
determines that an employee has suspected or confirmed infectious TB, the
physician or other licensed health care professional, as appropriate, shall
notify the employer and the employee as soon as feasible. (ii)
When the employer first identifies an individual with confirmed infectious
TB, the employer shall notify each employee who has had an exposure incident
involving that individual of his or her exposure to confirmed TB; and (iii)
When an exposure incident results in a TB skin test conversion, the employer
shall assure that a determination is made of the drug susceptibility of the M.
tuberculosis isolate from the source, unless the employer can demonstrate
that such a determination is not feasible. (iv)
When an exposure incident or a TB skin test conversion occurs, the employer
shall investigate and document the circumstances surrounding the exposure
incident or conversion (e.g. failure of engineering controls or work
practices and events leading to the exposure incident) to determine if
changes can be instituted to prevent similar occurrences in the future. (5)
Medical Removal Protection. (i) Each employee with suspected or confirmed
infectious TB shall be removed from the workplace until determined to be
noninfectious. (ii)
For each employee who is removed from the workplace under paragraph (g)(5)(i)
of this section, the employer shall maintain the total normal earnings,
seniority, and all other employee rights and benefits, including the
employee's right to his or her former job status, as if the employee had not
been removed from the employee's job or otherwise medically limited until the
employee is determined to be noninfectious or for a maximum of 18 months,
whichever comes first. (iii)
For each employee who is removed from his or her job under paragraph
(f)(4)(viii), Respiratory Protection, of this section the employer shall
transfer the employee to comparable work for which the employee is qualified
or can be trained in a short period (up to 6 months), where the use of
respiratory protection is not required. The employer shall maintain the total
normal earnings, seniority, and all other employee rights and benefits. If
there is no such work available, the employer shall maintain the employee's
total normal earnings, seniority, and all other employee rights and benefits
until such work becomes available or for a maximum of 18 months, whichever
comes first. (iv)
An employer's obligation to provide earnings, seniority and other benefits to
a removed employee may be reduced to the extent that the employee receives
compensation for earnings lost during the period of removal either from a
publicly or employer-funded compensation program or from employment with
another employer made possible by virtue of the employee's removal. (6)
Information Provided to Physician or Other Licensed Health Care
Professionals. (i) Each employer shall assure that all physicians or
other licensed health care professionals responsible for making
determinations and performing procedures as part of the medical surveillance
program are provided a copy of this regulation and, for those employees
required to wear respirators under this section, information regarding the
type of respiratory protection used, a description of the work effort
required, any special environmental conditions (e.g., heat, confined
space entry), additional requirements for protective clothing and equipment,
and the duration and frequency of usage of the respirator. (ii)
Each employer shall assure that the physician or other licensed health care
professional, as appropriate, who evaluates an employee after an exposure
incident is provided the following information: (A)
A description of the exposed employee's duties as they relate to the exposure
incident; (B)
Circumstances under which the exposure incident occurred; (C)
Any diagnostic test results, including drug susceptibility pattern or other
information relating to the source of exposure which could assist in the
medical management of the employee; and (D)
All of the employee's medical records relevant to the management of the
employee, including tuberculin skin testing results. (7)
Written Opinion. (i) Each employer shall obtain and provide the
employee with a copy of the written opinion of the physician or other
licensed health care professional, as appropriate, within 15 days of the
completion of all medical evaluations required by this section. (ii)
The written opinion shall be limited to the following information: (A)
The employee's TB skin test status; (B)
The employee's infectivity status; (C)
A statement that the employee has been informed of the results of the medical
evaluation; (D)
A statement that the employee has been told about any medical conditions
resulting from exposure to TB that require further evaluation or treatment; (E)
Recommendations for medical removal or work restrictions and the physician's
or other licensed health care professional's opinion regarding the employee's
ability to wear a respirator. (iii)
All other findings or diagnoses shall remain confidential and shall not be
included in the written report. (h)
Communication of Hazards and Training -- (1) Labels. (i) Air
systems that may reasonably be anticipated to contain aerosolized M.
tuberculosis shall be labeled "Contaminated Air -- Respiratory
Protection Required." The label shall be placed at all points where
ducts are accessed prior to a HEPA filter and at duct access points, fans,
and discharge outlets of non-HEPA filtered direct discharge systems. (ii)
Clinical and research laboratory wastes that are contaminated with M.
tuberculosis and are to be decontaminated outside of the immediate
laboratory shall be labeled with the biohazard symbol or placed in a red
container(s). (2)
Signs. (i) Signs shall be posted at the entrances to: (A)
Rooms or areas used to isolate an individual with suspected or confirmed
infectious TB; (B)
Areas where procedures or services are being performed on an individual with
suspected or confirmed infectious TB; and (C)
Clinical and research laboratories where M. tuberculosis is present. (ii)
When an AFB isolation room or area is vacated by an individual with suspected
or confirmed infectious TB, unless the individual has been medically
determined to be noninfectious, the sign shall remain posted at the entrance
until the room or area has been ventilated according to CDC recommendations
for a removal efficiency of 99.9 % (see Appendix C to this section). (iii)
Signs for AFB isolation rooms or areas, except as required in paragraph
(h)(2)(iv) of this section, shall be readily observable and shall bear the
following legend with symbol and text in white on a red background:
No Admittance Without Wearing a Type N95 or More Protective Respirator Note to paragraph (h)(2)(ii): Employers may include additional
information on signs provided it does not interfere with conveyance of this
message. (iv)
Signs at the entrances of clinical or research laboratories and autopsy
suites where procedures are being performed that may generate aerosolized M.
tuberculosis shall include the biohazard symbol, name and telephone
number of the laboratory director or other designated responsible person, the
infectious agent designation Mycobacterium tuberculosis, and special
requirements for entering the laboratory or autopsy room. (3)
Information and Training. (i) Each employer shall assure that each
employee with occupational exposure participates in a training program, which
must be provided at no cost to the employee and be made available at a
reasonable time and place. (ii)
Training shall be provided as follows: (A)
Before initial assignment to tasks where occupational exposure may occur; (B)
Within 60 days after the effective date of the standard; and (C)
At least annually thereafter, unless the employer can demonstrate that the
employee has the specific knowledge and skills required under paragraph
(h)(3)(vii) of this section. The employer must provide re-training to the
employee in any topic(s) in which specific knowledge and skills cannot be
demonstrated. Note to paragraph (h)(3)(ii): Training in the general topics under
paragraph (h)(3)(vii) of this section which has been provided in the past 12
months by a previous employer may be transferred to an employee's new
employer. However, the new employer must provide training in the
site-specific topics under paragraph (h)(3)(vii) in accordance with the
requirements of paragraph (h). (iii)
For employees who have received training on TB in the year preceding the
effective date of the standard, only training with respect to the provisions
of the standard that were not included in such training need be provided. The
annual retraining shall be conducted within one year from the date of the
training that occurred before the effective date of the standard. (iv)
Annual training for each employee shall be provided within one calendar year
of the employee's previous training. (v)
The employer shall provide additional training when changes such as
modification of tasks or procedures or institution of new tasks or procedures
affect the employee's occupational exposure. The additional training may be
limited to addressing the new or modified exposures. (vi)
Material appropriate in content and vocabulary to the educational level,
literacy, and language of employees shall be used. (vii)
The training program shall include an explanation of: (A)
The contents of this standard and the location of an accessible copy of the
regulatory text of this standard; (B)
The general epidemiology of TB, including Multidrug-Resistant TB (MDR-TB),
and the potential for exposure within the facility; the signs and symptoms of
TB, including the difference between tuberculosis infection and tuberculosis
disease; the modes of transmission of tuberculosis, including the possibility
of reinfection in persons with a positive tuberculin skin test; and the
personal health conditions that increase the employee's risk of developing TB
disease if infected (e.g., HIV infection, prolonged corticosteroid
therapy, other immunocompromising conditions); (C)
The employer's exposure control plan and respiratory protection program and
the means by which the employee can review the written plans; (D)
The tasks and other activities that may involve exposure to M.
tuberculosis; (E)
The use and limitations of methods that will prevent or reduce exposure,
including appropriate engineering controls, work practices, respiratory
protection, and site-specific control measures; (F)
Why a respirator is necessary, and the basis of selection of the respirators
used, the types of respirators used, upkeep and storage of the respirators
used, and their location and proper use, including procedures for inspection,
donning and removal, checking the fit and seals, and wearing the respirator. This
instruction shall allow sufficient practice to enable the employee to become
thoroughly familiar with and effective in performing these tasks; (G)
The employer's medical surveillance program, including the purpose of
tuberculin skin testing, the importance of a positive or negative skin test
result, anergy testing, and the importance of participation in the program; (H)
The procedures to follow if an exposure incident occurs, including the method
of reporting the incident and the medical management and follow-up that the
employer is required to provide, and the benefits and risks of prophylaxis;
and (I)
The procedures to follow if the employee develops signs or symptoms of TB
disease. (viii)
The person(s) conducting the training shall be knowledgeable in the subject
matter covered by the elements contained in the training program as it
relates to the workplace that the training will address. (ix)
The employer shall provide employees with an opportunity for interactive
questions and answers with the person conducting the training session. (i)
Recordkeeping -- (1) Medical Records. (i) Each employer shall
establish and maintain an accurate record for each employee with occupational
exposure, in accordance with 29 CFR 1910.1020. (ii)
This record shall include: (A)
The name, social security number, and job classification of the employee; (B)
A copy of all results of examinations; medical testing, including the
employee's tuberculin skin test status; and follow-up procedures; (C)
The employer's copy of the physician's or other licensed health care
professional's written opinion; and (D)
A copy of the information provided to the physician or other licensed health
care professional. (iii)
Confidentiality. The employer shall assure that employee medical records
required by paragraph (i) are: (A)
Kept confidential; and (B)
Not disclosed or reported without the employee's express written consent to
any person within or outside the workplace, except as required by this
section or as may be required by law. (iv)
The employer shall maintain the records required by paragraph (i)(1) for at
least the duration of employment plus 30 years, in accordance with 29 CFR
1910.1020. The medical records of employees who have worked for less than one
year for the employer need not be retained beyond the term of employment if
they are provided to the employee upon termination of employment. (2)
OSHA Illness and Injury Records. The employer shall record TB infection
or disease in accordance with 29 CFR 1904 and 29 CFR 1960, as applicable. (3)
Training Records. (i) Training records shall include the following
information: (A)
The dates of the training sessions; (B)
The contents or a summary of the training sessions; (C)
The names and qualifications of persons conducting the training; and (D)
The name and job classification of all persons attending the training
sessions. (ii)
Training records shall be maintained for 3 years from the date on which the
training occurred. (4)
Engineering Control Maintenance and Monitoring Records. (i)
Engineering control maintenance records shall include the following
information: (A)
Date; (B)
Equipment identification; (C)
Task performed; and (D)
Sign-off. (ii)
Performance monitoring records shall include the following information: (A)
Date and time; (B)
Location; (C)
Parameter measured, including units when appropriate; (D)
Results of monitoring; and (E)
Sign-off. (iii)
Engineering control maintenance and monitoring records shall be maintained
for three years. (5)
Availability. (i) Employee medical records required by paragraph
(i)(1), Recordkeeping, of this section shall be provided upon request for the
examination and copying to the subject employee, to anyone having the written
consent of the subject employee, to the Director, and to the Assistant
Secretary in accordance with 29 CFR 1910.1020. OSHA Illness and Injury
Records shall be accessible under the provisions of 29 CFR 1904 and 29 CFR
1960, as applicable. (ii)
Employee training records required by paragraph (i)(3), Recordkeeping, of
this section shall be provided upon request for examination and copying to
employees, to their representatives, to the Director, and to the Assistant
Secretary. (iii)
Engineering control maintenance and monitoring records required by paragraph
(i)(4), Recordkeeping, of this section shall be provided upon request for
examination and copying to employees, their representatives, to the Director,
and to the Assistant Secretary. (6)
Transfer of Records. (i) The employer shall comply with the
requirements involving transfer of records set forth in 29 CFR 1910.1020(h)
and 29 CFR 1904 and 29 CFR 1960, as applicable. (ii)
If the employer ceases to do business and there is no successor employer to
receive and retain the records for the prescribed period, the employer shall
notify the Director at least three months before their disposal and transmit
them to the Director, if required by the Director to do so, within the three
month period. (j)
Definitions. For the purposes of this section, the following shall
apply: Acid-fast bacilli (AFB) means bacteria that retain certain dyes after being washed in an acid
solution. Most acid-fast organisms are mycobacteria. Accredited laboratory means a laboratory that has participated in a quality assurance
program leading to a certification of competence administered by a
governmental or private organization that tests and certifies laboratories. Air-purifying respirator means a respirator that is designed to remove air contaminants from
the ambient air or air surrounding the respirator. AFB isolation room or area includes, but is not limited to, rooms,
areas, booths, tents, or other enclosures that are maintained at negative
pressure to adjacent areas in order to control the spread of aerosolized M.
tuberculosis. Anergy
means the inability of a person to react to skin test antigens (even if the
person is infected with the organisms tested) because of immunosuppression. Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and
Health, or designated representative. BCG (Bacille Calmette-Guerin) vaccine is a tuberculosis vaccine. Canister
or cartridge means a container with a filter, sorbent, or catalyst, or
a combination of these items, that removes specific air contaminants from the
air drawn through the container. Clinical laboratory is a laboratory or area of a facility that conducts routine and
repetitive operations for the diagnosis of TB such as preparing acid-fast
smears and culturing sputa or other clinical specimens for identification,
typing or susceptibility testing. Confirmed infectious tuberculosis is a disease state that has been diagnosed
by positive identification of M. tuberculosis from body fluid or
tissue through positive culture, positive gene probe, or positive polymerase
chain reaction (PCR). The disease state must be capable of being transmitted
to another individual (e.g., pulmonary or laryngeal TB or
extrapulmonary TB where the infected tissue is exposed and could generate
droplet nuclei). Conversion
means a change in tuberculin skin test results from negative to positive,
based upon current Centers for Disease Control and Prevention (CDC)
guidelines. Director
means the Director of the National Institute for Occupational Safety and
Health, U.S. Department of Health and Human Services, or designated
representative. Disposable respirator means a respiratory protective device that cannot be resupplied with
an unused filter or cartridge and that is to be discarded in its entirety
after its useful service life has been reached. Exposure incident means an event in which an employee has been exposed to an individual
with confirmed infectious TB or to air containing aerosolized M.
tuberculosis without the benefit of applicable exposure control measures
required by this section. Filter
means a component used in respirators to remove solid or liquid aerosols from
the inspired air. Fit factor
means a quantitative measure of the fit of a particular respirator on a
particular individual. High efficiency particulate air (HEPA) filter means a specialized filter that
is capable of removing 99.97 % of particles greater than or equal to 0.3
micrometer in diameter. High hazard procedures are procedures performed on an individual with suspected or confirmed
infectious tuberculosis in which the potential for being exposed to M.
tuberculosis is increased due to the reasonably anticipated generation of
aerosolized M. tuberculosis. Such procedures include, but are not
limited to, sputum induction, bronchoscopy, endotracheal intubation or
suctioning, aerosolized administration of pentamidine or other medications,
and pulmonary function testing. They also include autopsy, clinical, surgical
and laboratory procedures that may aerosolize M. tuberculosis. M. tuberculosis means Mycobacterium tuberculosis, the scientific name of the
bacillus that causes tuberculosis. Negative pressure means the relative air pressure difference between two areas. A room
that is under negative pressure has lower pressure than adjacent areas, which
keeps air from flowing out of the room and into adjacent rooms or areas. Negative pressure respirator means a respirator in which the air pressure
inside the facepiece is negative during inhalation with respect to the
ambient air pressure outside the respirator. Occupational exposure means reasonably anticipated contact, that results from the
performance of an employee's duties, with an individual with suspected or
confirmed infectious TB or air that may contain aerosolized M.
tuberculosis. Physician or other licensed health care professional means an individual whose legally
permitted scope of practice (i.e., license, registration, or certification)
allows him or her to independently provide or be delegated the responsibility
to provide some or all of the health care services required by paragraph (g)
of this section. Powered air-purifying respirator (PAPR) means an air-purifying respirator
that uses a blower to deliver air through the air-purifying element to the
wearer's breathing zone. Qualitative fit test means a pass/fail fit test to assess the adequacy of respirator fit
that relies on the respirator wearer's response to a challenge agent. Quantitative fit test means an assessment of the adequacy of respirator fit by numerically
measuring the amount of leakage into the respirator. Research laboratory is a laboratory that propagates and manipulates cultures of M.
tuberculosis in large volumes or high concentrations that are in excess
of those used for identification and typing activities common to clinical
laboratories. Respirator
means a device worn by an individual and intended to provide the wearer with
respiratory protection against inhalation of airborne contaminants. Suspected infectious tuberculosis means a potential disease state in which an
individual is known, or with reasonable diligence should be known, by the
employer to have one or more of the following conditions, unless the
individual's condition has been medically determined to result from a cause
other than TB: (1)
To be infected with M. tuberculosis and to have the signs or symptoms
of TB; (2)
To have a positive acid-fast bacilli (AFB) smear; or (3)
To have a persistent cough lasting 3 or more weeks and two or more symptoms
of active TB (e.g., bloody sputum, night sweats, weight loss, fever,
anorexia). An individual with suspected infectious TB has neither confirmed
infectious TB nor has he or she been medically determined to be
noninfectious. Tight-fitting facepiece means a respiratory inlet covering that is designed to form a complete
seal with the face. A half-facepiece covers the nose and mouth; a full
facepiece covers the nose, mouth, and eyes. Tuberculosis (TB) means a disease caused by M. tuberculosis. Tuberculosis infection means a condition in which living M. tuberculosis bacilli are
present in the body without producing clinically active disease. Although the
infected individual has a positive tuberculin skin test reaction, he or she
may have no symptoms related to the infection and may not be capable of
transmitting the disease. Tuberculosis disease is a condition in which living M. tuberculosis bacilli are
present in the body, producing clinical illness. The individual may or may
not be infectious. Tuberculin skin test means a method used to evaluate the likelihood that a person is
infected with M. tuberculosis. The method utilizes an intradermal
injection of tuberculin antigen with subsequent measurement of the reaction
induration. It is also referred to as a PPD skin test. Two-step testing is a baseline skin testing procedure used to identify a boosted skin
test reaction from that of a new infection. The procedure involves placing a
second skin test 1 to 3 weeks after an initial negative test. A positive
reaction on the second test indicates a boosted reaction. (k) Dates.
-- (1) Effective Date. The standard shall become effective on [insert
date 90 days after publication of final rule in the Federal Register]. (2)
Start-up dates. (i) Exposure control. The exposure control
provisions required by paragraph (c) of this section shall take effect on
[insert date 30 days after effective date of final rule]. (ii)
The Information and Training provisions required under paragraph
(h)(3), the Medical surveillance provisions required by paragraph (g),
and the Recordkeeping provisions required by paragraph (i) of this
section shall take effect on [insert date 60 days after effective date of
final rule]. (iii)
Work practices and Engineering controls. The work practice and
engineering control provisions required by paragraph (d) of this section
shall take effect on [insert date 90 days after effective date of final
rule]. For businesses with fewer than 20 employees, engineering controls
required by paragraph (d) of this section shall take effect [insert 270 days
after effective date of final rule]. Work practice controls that are directly
related to engineering controls being installed in accordance with this
paragraph shall be implemented as soon as those engineering controls are
implemented. (iv)
Respiratory protection. Respiratory protection provisions required by
paragraph (f) of this section shall take effect on [insert date 90 days after
effective date of final rule]. (v)
Labels and signs. The labels and signs provisions required by
paragraphs (h)(1) and (h)(2) of this section shall take effect on [insert
date 90 days after effective date of final rule]. (vi)
Clinical and research laboratories. The additional requirements for
Clinical and Research Laboratories contained in paragraphs (e)(1) through
(e)(3) shall take effect on [insert date 90 days after effective date of
final rule]. Appendix A to 1910.1035 -- Provisions for Employers Claiming Reduced
Responsibilities Under Paragraph (b), Application (Mandatory) (c) Exposure Control Paragraph
(c)(1)(i & ii) Exposure Determination (c)(2)(i)
Written Exposure Control Plan with the following elements: (c)(2)(i)(A)
The exposure determination (c)(2)(i)(B)
Procedures for providing information to employees about individuals
identified with suspected or confirmed infectious TB or air that may reasonably
be anticipated to contain aerosolized M. tuberculosis (c)(2)(i)(C)
Procedures for reporting an exposure incident (c)(2)(ii)
Procedures for identifying, masking or segregating and transferring
individuals with suspected or confirmed infectious TB (c)(2)(vi)
Documentation of the number of individuals with confirmed infectious TB
encountered in the past 12 months (c)(2)(vii)
(A-C) Accessible exposure control plan, reviewed annually and updated as
necessary, and made available to the Assistant Secretary and Director (d) Work Practice Procedures and Engineering Controls (d)(1)
Use of work practices to eliminate or minimize employee exposure (d)(2)
Implementation of the work practice procedures in the exposure control plan (d)(3)(i)
Identification and masking or segregating of individuals with suspected or
confirmed infectious TB (d)(3)(ii)
Temporary isolation of individuals who cannot be transferred within 5 hours (d)(5)(i-vii)
Engineering controls if temporary isolation is used (d)(6)
Provide information about TB hazards to temporary or personnel who may incur
occupational exposure (g) Medical Surveillance (g)(1)(i-iv)
Medical surveillance program for each employee with occupational exposure or
who has an exposure incident in one of the covered work settings, at no cost,
at a reasonable time, by a physician or other licensed health care
professional, according to current recommendations of the CDC and with
laboratory tests conducted by an accredited laboratory (g)(2)(i,
ii, iii, v, vi & vii) Explanation of terms: Medical history, Physical
examination, tuberculin skin testing, medical management and follow-up,
medical removal protection, and other related tests and procedures (g)(3)(i)(A)
Initial TB skin testing and medical history (NOTE: Annual skin testing and
medical histories are not required) (g)(3)(i)(B)
Medical history, TB skin testing and follow-up for employees who develop
signs or symptoms of TB (g)(3)(i)(C)
Medical history, TB skin testing and medical management and follow-up of
employees after an exposure incident (g)(4)(i)
Notification of employee and employer as soon as feasible about infectious TB
disease status of the employee (g)(4)(ii)
Notification of employees about previously unidentified individuals with
infectious TB (g)(4)(iii)
Determination of drug susceptibility of M. tuberculosis source after
an exposure incident (g)(4)(iv)
Investigations of exposure incidents and TB skin test conversions (g)(5)(i,
ii & iv) Medical removal and protection of benefits for individuals with
infectious TB (g)(6)(i
& ii) Information provided to the physician or other licensed health care
professional (g)(7)(i-iii)
Physician or other licensed health care professional's written opinion (h) Communication of Hazards and Training (h)(1)(i)
If temporary isolation is used, label air systems that may reasonably be
anticipated to contain aerosolized M. tuberculosis (h)(2)(i)(A)
If temporary isolation is used, post signs at entrance to temporary isolation (h)(2)(ii)
When temporary isolation room or area is vacated by an individual with
suspected or confirmed infectious TB, ventilate for an appropriate period (h)(2)(iii)
Signs for temporary isolation rooms or areas must have a stop sign with the
legend "No Admittance Without Wearing a Type N95 or More Protective
Respirator" (h)(3)(i-viii)
Annual training with specified elements for employees with occupational
exposure (i) Recordkeeping (i)(1)(i-iv)
Medical Records (i)(2)
OSHA Illness and Injury Records (i)(3)(i
& ii) Training Records (i)(4)(i-iii)
If temporary isolation is used, engineering control maintenance records (i)(5)(i
& ii) Availability of medical and training records (i)(6)(i
& ii) Transfer of records (k) Dates (k)(1)
Effective date (k)(2)(i,
ii & iii) Start up dates for exposure control, medical surveillance,
information and training, recordkeeping, and work practices and engineering
controls Appendix B to 1910.1035 -- Fit Testing Procedures (Mandatory) Part I. Approved Fit
Test Protocols The
employer shall conduct fit testing using the following procedures. These
provisions apply to both QLFT and QNFT. 1.
The test subject shall be allowed to pick the most acceptable respirator from
a selection of respirators of various sizes and models. 2.
Prior to the selection process, the test subject shall be shown how to put on
a respirator, how it should be positioned on the face, how to set strap
tension and how to determine an acceptable fit. A mirror shall be available
to assist the subject in evaluating the fit and positioning the respirator. This
instruction may not constitute the subject's formal training on respirator
use, as it is only a review. 3.
The test subject shall be informed that he or she is being asked to select
the respirator that provides the most acceptable fit. Each respirator represents
a different size and shape, and if fitted and used properly, will provide
adequate protection. 4.
The test subject shall be instructed to hold each chosen facepiece up to the
face and eliminate those that obviously do not give an acceptable fit. 5.
The more acceptable facepieces are noted; the most acceptable mask is donned
and worn at least five minutes to assess acceptability. Assistance in
assessing acceptability can be given by discussing the points in item 6
below. If the test subject is not familiar with using a particular
respirator, the test subject shall be directed to don the mask several times
and to adjust the straps each time to become adept at setting proper tension
on the straps. 6.
Assessment of acceptability shall include reviewing the following points with
the test subject and allowing the test subject adequate time to determine the
acceptability of the respirator: (a)
Position of the mask on the nose, (b)
Room for eye protection, (c)
Room to talk; (d)
Position of mask on face and cheeks. 7.
The following criteria shall be used to help determine the adequacy of the
respirator fit: (a)
Chin properly placed; (b)
Adequate strap tension, not overly tightened; (c)
Fit across nose bridge; (d)
Respirator of proper size to span distance from nose to chin; (e)
Tendency of respirator to slip; (f)
Self-observation in mirror to evaluate fit and respirator position. 8.
The test subject shall conduct the negative and positive pressure fit checks
as described in this appendix or other fit check procedures recommended by
the respirator manufacturer providing equivalent protection to the procedures
in this appendix. Before conducting the negative or positive pressure fit
checks, the subject shall be told to seat the mask on the face by moving the
head from side-to-side and up and down slowly while taking in a few slow deep
breaths. Another facepiece shall be selected and retested if the test subject
fails the fit check tests. 9.
The test shall not be conducted if there is any hair growth between the skin and
the facepiece sealing surface, such as stubble beard growth, beard, mustache
or sideburns that cross the respirator sealing surface. Any type of apparel
which interferes with a satisfactory fit shall be altered or removed. 10.
If a test subject exhibits difficulty in breathing during the tests, she or
he shall be referred to a physician or other licensed health care
professional, as appropriate, to determine whether the test subject can wear
a respirator while performing her or his duties. 11.
If the employee finds the fit of the respirator unacceptable, the test
subject shall be given the opportunity to select a different respirator and
to be retested. 12.
Exercise regimen. Prior to the commencement of the fit test, the test
subject shall be given a description of the fit test and the test subject's
responsibilities during the test procedure. The description of the process
shall include a description of the test exercises that the subject will be
performing. The respirator to be tested shall be worn for at least 5 minutes
before the start of the fit test. 13.
Test Exercises. The test subject shall perform exercises, in the test
environment, while wearing any applicable safety equipment that may be worn
during actual respirator use which could interfere with fit, in the manner
described below: (a)Normal
breathing. In a normal standing position, without talking, the subject
shall breathe normally. (b)
Deep breathing. In a normal standing position, the subject shall breathe
slowly and deeply, taking caution so as to not hyperventilate. (c)
Turning head side to side. Standing in place, the subject shall slowly
turn his or her head from side to side between the extreme positions on each
side. The head shall be held at each extreme momentarily so the subject can inhale
at each side. (d)
Moving head up and down. Standing in place, the subject shall slowly move
his/her head up and down. The subject shall be instructed to inhale in the up
position (i.e., when looking toward the ceiling). (e)
Talking. The subject shall talk out loud slowly and loud enough so as to
be heard clearly by the test conductor. The subject can read from a prepared
text such as the Rainbow Passage, count backward from 100, or recite a
memorized poem or song. Rainbow Passage When
the sunlight strikes raindrops in the air, they act like a prism and form a
rainbow. The rainbow is a division of white light into many beautiful colors.
These take the shape of a long round arch, with its path high above, and its
two ends apparently beyond the horizon. There is, according to legend, a
boiling pot of gold at one end. People look, but no one ever finds it. When a
man looks for something beyond reach, his friends say he is looking for the
pot of gold at the end of the rainbow. (f)
Grimace. The test subject shall grimace by smiling or frowning. (Only for
QNFT testing, not performed for QLFT) (g)
Bending over. The test subject shall bend at the waist as if he/she were
to touch his/her toes. Jogging in place shall be substituted for this
exercise in those test environments such as shroud type QNFT units which
prohibit bending at the waist. (h)
Normal breathing. Same as exercise (a). Each test exercise shall be
performed for one minute except for the grimace exercise which shall be
performed for 15 seconds. The
test subject shall be questioned by the test conductor regarding the
acceptability of the respirator upon completion of the protocol. If it has
become unacceptable, another model of respirator shall be tried. B. Qualitative Fit Test (QLFT) Protocols 1.
General (a)
The employer shall assign specific individuals who shall assume full
responsibility for implementing the respirator qualitative fit test program. (b)
The employer shall ensure that persons administering QLFT are able to prepare
test solutions, calibrate equipment and perform tests properly, recognize
invalid tests, and assure that test equipment is in proper working order. (c)
The employer shall assure that QLFT equipment is kept clean and well
maintained so as to operate within the parameters for which it was designed. 2.
Isoamyl Acetate Protocol Note: This
protocol is not appropriate, by itself, for fit testing particulate
respirators. If chosen for use in fit testing particulate respirators, the
respirator must be equipped with an organic vapor cartridge, provided the
employee will be using the same facepiece in the work setting except that it
will be equipped with particulate filters. (a)
Odor threshold screening. The odor threshold screening test, performed
without wearing a respirator, is intended to determine if the individual
tested can detect the odor of isoamyl acetate. (1)
Three 1 liter glass jars with metal lids are required. (2)
Odor free water (e.g. distilled or spring water) at approximately 25
degrees C shall be used for the solutions. (3)
The isoamyl acetate (IAA) (also known at isopentyl acetate) stock solution is
prepared by adding 1 cc of pure IAA to 800 cc of odor free water in a 1 liter
jar and shaking for 30 seconds. A new solution shall be prepared at least
weekly. (4)
The screening test shall be conducted in a room separate from the room used
for actual fit testing. The two rooms shall be well ventilated to prevent the
odor of IAA from becoming evident in the general room air where testing takes
place. (5)
The odor test solution is prepared in a second jar by placing 0.4 cc of the
stock solution into 500 cc of odor free water using a clean dropper or
pipette. The solution shall be shaken for 30 seconds and allowed to stand for
two to three minutes so that the IAA concentration above the liquid may reach
equilibrium. This solution shall be used for only one day. (6)
A test blank shall be prepared in a third jar by adding 500 cc of odor free
water. (7)
The odor test and test blank jars shall be labeled 1 and 2 for jar
identification. Labels shall be placed on the lids so they can be
periodically peeled off and switched to maintain the integrity of the test. (8)
The following instruction shall be typed on a card and placed on the table in
front of the two test jars (i.e., 1 and 2): The purpose of this test is to
determine if you can smell banana oil at a low concentration. The two bottles
in front of you contain water. One of these bottles also contains a small
amount of banana oil. Be sure the covers are on tight, then shake each bottle
for two seconds. Unscrew the lid of each bottle, one at a time, and sniff at
the mouth of the bottle. Indicate to the test conductor which bottle contains
banana oil. (9)
The mixtures used in the IAA odor detection test shall be prepared in an area
separate from where the test is performed, in order to prevent olfactory
fatigue in the subject. (10)
If the test subject is unable to correctly identify the jar containing the
odor test solution, the IAA qualitative fit test shall not be performed. (11)
If the test subject correctly identifies the jar containing the odor test
solution, the test subject may proceed to respirator selection and fit
testing. (b)
Isoamyl acetate fit test. (1) The fit test chamber shall be similar to
a clear 55-gallon drum liner suspended inverted over a 2-foot diameter frame
so that the top of the chamber is about 6 inches above the test subject's
head. The inside top center of the chamber shall have a small hook attached. (2)
Each respirator used for the fitting and fit testing shall be equipped with
organic vapor cartridges or offer protection against organic vapors. (3)
After selecting, donning, and properly adjusting a respirator, the test
subject shall wear it to the fit testing room. This room shall be separate
from the room used for odor threshold screening and respirator selection, and
shall be well ventilated, as by an exhaust fan or lab hood, to prevent the
test medium that is not contained will be removed from the general room air. (4)
A copy of the test exercises and any prepared text from which the subject is
to read shall be taped to the inside of the test chamber. (5)
Upon entering the test chamber, the test subject shall be given a 6-inch by
5-inch piece of paper towel, or other porous, absorbent, single-ply material,
folded in half and wetted with 0.75 cc of pure IAA. The test subject shall
hang the wet towel on the hook at the top of the chamber. (6)
Allow two minutes for the IAA test concentration to stabilize before starting
the fit test exercises. This would be an appropriate time to talk with the
test subject; to explain the fit test, the importance of his/her cooperation,
and the purpose for the test exercises; or to demonstrate some of the
exercises. (7)
If at any time during the test, the subject detects the banana like odor of
IAA, the test is failed. The subject shall quickly exit from the test chamber
and leave the test area to avoid olfactory fatigue. (8)
If the test is failed, the subject shall return to the selection room and
remove the respirator. The test subject shall repeat the odor sensitivity
test, select and put on another respirator, return to the test area and again
begin the fit test procedure described in (1) through (7) above. The process
continues until a respirator that fits well has been found. Should the odor
sensitivity test be failed, the subject shall wait about 5 minutes before
retesting. Odor sensitivity will usually have returned by this time. (9)
When the subject wearing the respirator passes the test, its efficiency shall
be demonstrated for the subject by having the subject break the face seal and
take a breath before exiting the chamber. (10)
When the test subject leaves the chamber, the subject shall remove the
saturated towel and return it to the person conducting the test, so there is
no significant IAA concentration buildup in the chamber during subsequent
tests. The used towels shall be kept in a self sealing bag to keep the test
area from being contaminated. 3. Saccharin Solution Aerosol Protocol The
entire screening and testing procedure shall be explained to the test subject
prior to the conduct of the screening test. (a)
Taste threshold screening. The saccharin taste threshold screening, performed
without wearing a respirator, is intended to determine whether the individual
being tested can detect the taste of saccharin. (1)
During threshold screening as well as during fit testing, subjects shall wear
an enclosure about the head and shoulders that is approximately 12 inches in
diameter by 14 inches tall with at least the front portion clear and that
allows free movements of the head when a respirator is worn. An enclosure
substantially similar to the 3M hood assembly, parts # FT 14 and # FT 15
combined, is adequate. (2)
The test enclosure shall have a 3/4-inch hole in front of the test subject's
nose and mouth area to accommodate the nebulizer nozzle. (3)
The test subject shall don the test enclosure. Throughout the threshold
screening test, the test subject shall breathe through his/her slightly open
mouth with tongue extended. (4)
Using a nebulizer device such as the DeVilbiss Model 40 Inhalation Medication
Nebulizer or equivalent, the test conductor shall spray the threshold
check solution into the enclosure. This nebulizer shall be clearly marked
to distinguish it from the fit test solution nebulizer. (5)
The threshold check solution consists of 0.83 grams of sodium
saccharin USP in 100 ml of warm water. It can be prepared by putting 1 ml of
the fit test solution (see (b)(5) below) in 100 ml of distilled water. (6)
To produce the aerosol, the nebulizer bulb is firmly squeezed so that it
collapses completely, and is then released and allowed to fully expand. (7)
Ten squeezes are repeated rapidly and then the test subject is asked whether
the saccharin can be tasted. (8)
If the first response is negative, ten more squeezes are repeated rapidly and
the test subject is again asked whether the saccharin is tasted. (9)
If the second response is negative, ten more squeezes are repeated rapidly
and the test subject is again asked whether the saccharin is tasted. (10)
The test conductor will take note of the number of squeezes required to
solicit a taste response. (11)
If the saccharin is not tasted after 30 squeezes (step 10), the test subject
may not perform the saccharin fit test. (12)
If a taste response is elicited, the test subject shall be asked to take note
of the taste for reference in the fit test. (13)
Correct use of the nebulizer means that approximately 1 ml of liquid is used
at a time in the nebulizer body. (14)
The nebulizer shall be thoroughly rinsed in water, shaken dry, and refilled
at least each morning and afternoon or at least every four hours. (b)
Saccharin solution aerosol fit test procedure. (1)
The test subject may not eat, drink (except plain water), smoke, or chew gum
for 15 minutes before the test. (2)
The fit test uses the same enclosure described in (a) above. (3)
The test subject shall don the enclosure while wearing the respirator
selected in section I.A. above. The respirator shall be properly adjusted and
equipped with a particulate filter(s). (4)
A second nebulizer device such as the DeVilbiss Model 40 Inhalation
Medication Nebulizer or equivalent is used to spray the fit test solution
into the enclosure. This nebulizer shall be clearly marked to distinguish it from
the screening test solution nebulizer. (5)
The fit test solution is prepared by adding 83 grams of sodium saccharin to
100 ml of warm water. (6)
As before, the test subject shall breathe through the slightly open mouth
with tongue extended. (7)
The nebulizer is inserted into the hole in the front of the enclosure and the
fit test solution is sprayed into the enclosure using the same number of
squeezes required to elicit a taste response in the screening test. A minimum
of 10 squeezes is required. (8)
After generating the aerosol the test subject shall be instructed to perform
the exercises in section I. A. 13 above. (9)
Every 30 seconds the aerosol concentration shall be replenished using one
half the number of squeezes as initially. (10)
The test subject shall indicate to the test conductor if at any time during
the fit test the taste of saccharin is detected. (11)
If the taste of saccharin is detected, the fit is deemed unsatisfactory and a
different respirator shall be tried. 4.
Bitrex (Denatonium benzoate) Solution Aerosol Qualitative Fit Test Protocol The
Bitrex (Denatonium benzoate) solution aerosol QLFT protocol uses the
published saccharin test protocol because of its current acceptance and past
validation. Bitrex is routinely used as a taste aversion agent in household
liquids which children should not be drinking and is endorsed by the American
Medical Association, the National Safety Council, and the American
Association of Poison Control Centers. The entire screening and testing
procedure shall be explained to the test subject prior to the conduct of the
screening test. (a)
Taste Threshold Screening. The Bitrex taste threshold screening, performed
without wearing a respirator, is intended to determine whether the individual
being tested can detect the taste of Bitrex. (1)
During threshold screening as well as during fit testing, subjects shall wear
an enclosure about the head and shoulders that is approximately 12 inches
(30.5 cm) in diameter by 14 inches (35.6 cm) tall. The front portion of the enclosure
shall be clear from the respirator and allow free movement of the head when a
respirator is worn. An enclosure substantially similar to the 3M hood
assembly, parts # 14 and # 15 combined, is adequate. (2)
The test enclosure shall have a 3/4 inch (1.9 cm) hole in front of the test
subject's nose and mouth area to accommodate the nebulizer nozzle. (3)
The test subject shall don the test enclosure. Throughout the threshold
screening test, the test subject shall breathe through his or her slightly
open mouth with tongue extended. (4)
Using a nebulizer device such as a DeVilbiss Model 40 Inhalation Medication
Nebulizer or equivalent, the test conductor shall spray the threshold
check solution into the enclosure. This nebulizer shall be clearly marked
to distinguish it from the fit test solution nebulizer. (5)
The threshold check solution consists of 13.5 milligrams of Bitrex in
100 ml of 5 % NaCl solution in distilled water. (6)
To produce the aerosol, the nebulizer bulb is firmly squeezed so that the bulb
collapses completely, and is then released and allowed to fully expand. (7)
Ten squeezes are repeated rapidly and then the test subject is asked whether
the Bitrex can be tasted. (8)
If the first response is negative, ten more squeezes are repeated rapidly and
the test subject is again asked whether the Bitrex is tasted. (9)
If the second response is negative, ten more squeezes are repeated rapidly
and the test subject is again asked whether the Bitrex is tasted. (10)
The test conductor will take note of the number of squeezes required to
solicit a taste response. (11)
If the Bitrex is not tasted after 30 squeezes (step 10), the test subject may
not perform the Bitrex fit test. (12)
If a taste response is elicited, the test subject shall be asked to take note
of the taste for reference in the fit test. (13)
Correct use of the nebulizer means that approximately 1 ml of liquid is used
at a time in the nebulizer body. (14)
The nebulizer shall be thoroughly rinsed in water, shaken to dry, and
refilled at least each morning and afternoon or at least every four hours. (b)
Bitrex solution aerosol fit test procedure. (1)
The test subject may not eat, drink (except plain water), smoke, or chew gum
for 15 minutes before the test. (2)
The fit test uses the same enclosure described in (a) above. (3)
The test subject shall don the enclosure while wearing the respirator
selected in section I.A. of this appendix. The respirator shall be properly
adjusted and equipped with a particulate filter(s). (4)
A second nebulizer device such as a DeVilbiss Model 40 Inhalation Medication
Nebulizer or equivalent is used to spray the fit test solution into the
enclosure. This nebulizer shall be clearly marked to distinguish it from the
screening test solution nebulizer. (5)
The fit test solution is prepared by adding 337.5 mg of Bitrex in 200 ml of a
5 % solution of NaCl in warm water. (6)
As before, the test subject shall breathe through his or her slightly open
mouth with tongue extended. (7)
The nebulizer is inserted into the hole in the front of the enclosure and the
fit test solution is sprayed into the enclosure using the same number of
squeezes required to elicit a taste response in the screening test. (8)
After generating the aerosol the test subject shall be instructed to perform the
exercises in section I.A.13 of this appendix. (9)
Every 30 seconds the aerosol concentration shall be replenished using half
the number of squeezes as initially. (10)
The test subject shall indicate to the test conductor if at any time during
the fit test the taste of Bitrex is detected. (11)
If the taste of Bitrex is detected, the fit is deemed unsatisfactory and a
different respirator shall be tried. 5.
Irritant Fume Protocol (a)
The respirator to be tested shall be equipped with high-efficiency particulate
filters (i.e., HEPA, N100, R100, or P100) . (b)
No form of test enclosure or hood for the test subject shall be used. (c)
The test subject shall be allowed to smell a weak concentration of the
irritant smoke before the respirator is donned to become familiar with its
irritating properties. (d)
Break both ends of a ventilation smoke tube containing stannic chloride. Attach
one end of the smoke tube to an aspirator squeeze bulb and cover the other
end with a short piece of tubing to prevent potential injury from the jagged
end of the smoke tube. (e)
Advise the test subject that the smoke can be irritating to the eyes and
instruct the subject to keep his or her eyes closed while the test is
performed. (f)
The test conductor shall direct the stream of irritant smoke from the smoke
tube towards the face seal area of the test subject beginning at least 12
inches from the facepiece and gradually moving to within one inch, moving
around the whole perimeter of the mask. (g)
The exercises identified in section I.A. 13 above shall be performed by the
test subject while the respirator seal is being challenged by the smoke. (h)
Each test subject passing the smoke test without evidence of a response
(involuntary cough) shall be given a sensitivity check of the smoke from the
same tube once the respirator has been removed to determine whether he or she
reacts to the smoke. Failure to evoke a response shall void the fit test. (i)
The fit test shall be performed in a location with exhaust ventilation
sufficient to prevent general contamination of the testing area by the test
agent. C. Quantitative Fit Test (QNFT) Protocols The
following quantitative fit testing procedures have been demonstrated to be
acceptable: (1)
Quantitative fit testing using a non-hazardous challenge aerosol (such as
corn oil or sodium chloride) generated in a test chamber, and employing
instrumentation to quantify the fit of the respirator. (2)
Quantitative fit testing using ambient aerosol as the challenge agent and
appropriate instrumentation (condensation nuclei counter) to quantify the
respirator fit. (3)
Quantitative fit testing using controlled negative pressure and appropriate
instrumentation to measure the volumetric leak rate of a facepiece to
quantify the respirator fit. 1.
General (a)
The employer shall assign specific individuals who shall assume full
responsibility for implementing the respirator quantitative fit test program. (b)
The employer shall ensure that persons administering QNFT are able to
calibrate equipment and perform tests properly, recognize invalid tests,
calculate fit factors properly and assure that test equipment is in proper
working order. (c)
The employer shall assure that QNFT equipment is kept clean, maintained and
calibrated according to the manufacturer's instructions so as to operate at
the parameters for which it was designed. 2. Generated Aerosol Protocol (a) Apparatus. (1) Instrumentation. Aerosol generation,
dilution, and measurement systems using particulates (corn oil or sodium
chloride) or gases or vapors as test aerosols shall be used for quantitative
fit testing. (2)
Test chamber. The test chamber shall be large enough to permit all
test subjects to perform freely all required exercises without disturbing the
challenge agent concentration or the measurement apparatus. The test chamber
shall be equipped and constructed so that the challenge agent is effectively
isolated from the ambient air, yet uniform in concentration throughout the
chamber. (3)
When testing air-purifying respirators, the normal filter or cartridge
element shall be replaced with a high-efficiency particulate filter (i.e.,
HEPA, N100, R100, P100) supplied by the same manufacturer in the case of
particulate QNFT aerosols or a sorbent offering contaminant penetration
protection equivalent to high-efficiency filters where the QNFT test agent is
a gas or vapor. (4)
The sampling instrument shall be selected so that a computer record or strip
chart record may be made of the test showing the rise and fall of the
challenge agent concentration with each inspiration and expiration at fit
factors of at least 2,000. Integrators or computers that integrate the amount
of test agent penetration leakage into the respirator for each exercise may
be used, provided a record of the readings is made. (5)
The combination of substitute air-purifying elements, challenge agent and
challenge agent concentration shall be such that the test subject is not
exposed in excess of an established exposure limit for the challenge agent at
any time during the testing process based upon the length of the exposure and
the exposure limit duration. (6)
The sampling port on the test specimen respirator shall be placed and
constructed so that no leakage occurs around the port (e.g. where the
respirator is probed), a free air flow is allowed into the sampling line at
all times and so that there is no interference with the fit or performance of
the respirator. The in-mask sampling device (probe) shall be designed and
used so that the air sample is drawn from the breathing zone of the test subject,
midway between the nose and mouth and with the probe extending into the
facepiece cavity at least 1/4 inch. (7)
The test set-up shall permit the person administering the test to observe the
test subject inside the chamber during the test. (8)
The equipment generating the challenge atmosphere shall maintain the
concentration of challenge agent constant to within a 10 percent variation
for the duration of the test. (9)
The time lag (interval between an event and the recording of the event on the
strip chart or computer or integrator) shall be kept to a minimum. There
shall be a clear association between the occurrence of an event and its being
recorded. (10)
The sampling line tubing for the test chamber atmosphere and for the
respirator sampling port shall be of equal diameter and of the same material.
The length of the two lines shall be equal. (11)
The exhaust flow from the test chamber shall pass through an appropriate
filter (i.e., high efficiency or sorbent) before release. (12)
When sodium chloride aerosol is used, the relative humidity inside the test
chamber shall not exceed 50 percent. (13)
The limitations of instrument detection shall be taken into account when
determining the fit factor. (14)
Test respirators shall be maintained in proper working order and inspected
for deficiencies such as cracks, missing valves and gaskets, etc. (b)
Procedural Requirements. (1) When performing the initial positive or
negative pressure fit check, the sampling line shall be crimped closed in
order to avoid air pressure leakage during either of these fit checks. (2)
An abbreviated screening QLFT test may be utilized in order to quickly
identify poor fitting respirators which passed the positive and/or negative
pressure test and thus reduce the amount of QNFT time. The use of the CNC
QNFT instrument in the count mode is another method that can be used to
obtain a quick estimate of fit and eliminate poor fitting respirators before
going on to perform a full QNFT. (3)
A reasonably stable challenge agent concentration shall be measured in the
test chamber prior to testing. For canopy or shower curtain type of test
units the determination of the challenge agent stability may be established
after the test subject has entered the test environment. (4)
Immediately after the subject enters the test chamber, the challenge agent
concentration inside the respirator shall be measured to ensure that the peak
penetration does not exceed 5 percent for a half mask or 1 percent for a full
facepiece respirator. (5)
A stable challenge concentration shall be obtained prior to the actual start
of testing. (6)
Respirator restraining straps shall not be over tightened for testing. The
straps shall be adjusted by the wearer without assistance from other persons
to give a reasonable fit typical of normal use. (7)
The test shall be terminated whenever any single peak penetration exceeds 5
percent for half masks and 1 percent for full facepiece respirators. The test
subject shall be refitted and retested. (c)
Calculation of fit factors. (1) The fit factor shall be determined for
the quantitative fit test by taking the ratio of the average chamber
concentration to the concentration measured inside the respirator for each
test exercise except the grimace exercise. (2)
The average test chamber concentration shall be calculated as the arithmetic
average of the concentration measured before and after each test (i.e., 8
exercises) or the arithmetic average of the concentration measured before and
after each exercise or the true average measured continuously during the
respirator sample. (3)
The concentration of the challenge agent inside the respirator shall be
determined by one of the following methods: (i)
Average peak penetration method, which is the method of determining test
agent penetration into the respirator utilizing a strip chart recorder,
integrator, or computer. The agent penetration is determined by an average of
the peak heights on the graph or by computer integration, for each exercise
except the grimace exercise. Integrators or computers that calculate the
actual test agent penetration into the respirator for each exercise also meet
the requirements of the average peak penetration method. (ii)
Maximum peak penetration method means the method of determining test agent
penetration in the respirator as determined by strip chart recordings of the
test. The highest peak penetration for a given exercise is taken to be
representative of average penetration into the respirator for that exercise. (iii)
Integration by calculation of the area under the individual peak for each
exercise except the grimace exercise is another method. This includes
computerized integration. (iv)
The calculation of the overall fit factor using individual exercise fit
factors involves first converting the exercise fit factors to penetration
values, determining the average, and then converting that result back to a
fit factor is also appropriate. This procedure is described in the following
equation:
Where
ff1, ff2, ff3, etc. are the fit factors for
exercise 1,2,3, etc. (4)
The test subject shall not be permitted to wear a half mask or quarter
facepiece respirator unless a minimum fit factor of 100 is obtained, or a
full facepiece respirator unless a minimum fit factor of 500 is obtained. (5)
Filters used for quantitative fit testing shall be replaced whenever
increased breathing resistance is encountered, or when the test agent has
altered the integrity of the filter media. Organic vapor cartridges/canisters
shall be replaced if there is any indication of breakthrough by a test agent. 3. Ambient Aerosol Condensation Nuclei Counter (CNC) Protocol The
ambient aerosol condensation nuclei counter (CNC) quantitative fit testing
(PortacountTM) protocol quantitatively fit tests respirators with
the use of a probe. The probed respirator is only used for quantitative fit
tests. A probed respirator has a special sampling device, installed on the
respirator, that allows the probe to sample the air from inside the mask. A
probed respirator is required for each make, model, and size that is intended
to be used and can be obtained from the respirator manufacturer or
distributor. The CNC instrument manufacturer TSI also provides probe
attachments (TSI sampling adapters) that permit fit testing in an employee's
own respirator. A minimum fit factor pass level of 100 is necessary for a
half-mask respirator and a minimum fit factor of at least 500 is required for
a full facepiece respirator. The Agency does not recommend the use of
homemade sampling adapters. The entire screening and testing procedure shall
be explained to the test subject prior to the conduct of the screening test. (a)
Portacount Fit Test Requirements. (1)
Check the respirator to make sure the respirator is fitted with a high
efficiency filter (i.e., HEPA, N100, R100, P100) and that the sampling probe
and line are properly attached to the facepiece. (2)
Instruct the person to be tested to don the respirator several minutes before
the fit test starts. This purges the particles inside the respirator and
permits the wearer to make certain the respirator is comfortable. This
individual should have already been trained on how to wear the respirator
properly. (3)
Check the following conditions for the adequacy of the respirator fit: Chin
properly placed; Adequate strap tension, not overly tightened; Fit across
nose bridge; Respirator of proper size to span distance from nose to chin;
Tendencies for the respirator to slip; Self-observation in a mirror to
evaluate fit; and respirator position. (4)
Have the person wearing the respirator do a fit check. If leakage is
detected, determine the cause. If leakage is from a poorly fitting facepiece,
try another size of the same type of respirator. (5)
Follow the instructions for operating the Portacount and proceed with the
test. (b)
Portacount Test Exercises -- (1) Normal breathing. In a normal
standing position, without talking, the subject shall breathe normally for 1
minute. (2)
Deep breathing. In a normal standing position, the subject shall
breathe slowly and deeply for 1 minute, taking caution so as not to
hyperventilate. (3)
Turning head side to side. Standing in place, the subject shall slowly
turn his or her head from side to side between the extreme positions on each
side for 1 minute. The head shall be held at each extreme momentarily so the
subject can inhale at each side. (4)
Moving head up and down. Standing in place, the subject shall slowly
move his or her head up and down for 1 minute. The subject shall be
instructed to inhale in the up position (i.e., when looking toward the
ceiling). (5)
Talking. The subject shall talk out loud slowly and loud enough so as
to be heard clearly by the test conductor. The subject can read from a
prepared text such as the Rainbow Passage, count backward from 100, or recite
a memorized poem or song for 1 minute. (6)
Grimace. The test subject shall grimace by smiling or frowning for 15
seconds. (7)
Bending Over. The test subject shall bend at the waist as if he or she
were to touch his or her toes for 1 minute. Jogging in place shall be
substituted for this exercise in those test environments such as shroud type
QNFT units that prohibit bending at the waist. (8)
Normal Breathing. Remove and re-don the respirator within a one-minute
period. Then, in a normal standing position, without talking, the subject
shall breathe normally for 1 minute. After
the test exercises, the test subject shall be questioned by the test
conductor regarding the acceptability of the respirator upon completion of
the protocol. If it has become unacceptable, another model of respirator
shall be tried. (c)
Portacount Test Instrument. (1) The Portacount will automatically stop
and calculate the overall fit factor for the entire set of exercises. The
overall fit factor is what counts. The Pass or Fail message will indicate
whether or not the test was successful. If the test was a Pass, the fit test
is over. (2)
A record of the test needs to be kept on file assuming the fit test was
successful. The record must contain the test subject's name; overall fit
factor; make, model and size of respirator used, and date tested. 4. Controlled Negative Pressure (CNP) Protocol The
CNP protocol provides an alternative to aerosol fit test methods. The CNP fit
test method technology is based on exhausting air from a temporarily sealed
respirator facepiece to generate and then maintain a constant negative
pressure inside the facepiece. The rate of air exhaust is controlled so that
a constant negative pressure is maintained in the respirator during the fit
test. The level of pressure is selected to replicate the mean inspiratory
pressure that causes leakage into the respirator under normal use conditions.
With pressure held constant, air flow out of the respirator is equal to air
flow into the respirator. Therefore, measurement of the exhaust stream that
is required to hold the pressure in the temporarily sealed respirator
constant yields a direct measure of leakage air flow into the respirator. The
CNP fit test method measures leak rates through the facepiece as a method for
determining the facepiece fit for negative pressure respirators. The CNP
instrument manufacturer Dynatech Nevada also provides attachments (sampling
manifolds) that replace the filter cartridges to permit fit testing in an
employee's own respirator. To perform the test, the test subject closes his
or her mouth and holds his or her breath, then an air pump removes air from
the respirator facepiece at a pre-selected constant pressure. The facepiece
fit is expressed as the leak rate through the facepiece, expressed as
milliliters per minute. The quality and validity of the CNP fit tests are
determined by the degree to which the in-mask pressure tracks the challenge
pressure during the system measurement time of approximately five seconds. Instantaneous
feedback in the form of a real-time pressure trace of the in-mask pressure is
provided and used to determine test validity and quality. A minimum fit
factor pass level of 100 is necessary for a half-mask respirator and a
minimum fit factor of at least 500 is required for a full facepiece
respirator. The
entire screening and testing procedure shall be explained to the test subject
prior to the conduct of the screening test. (a)
CNP Fit Test Requirements -- (1) The instrument shall have a
non-adjustable challenge pressure of 15.0 mm water pressure. (2)
The CNP system defaults for challenge pressure shall be tested at -0.58
inches of water and the modeled inspiratory flow rate shall be 53.8 liters
per minute. Note: CNP
systems have built-in capability to conduct fit testing that is specific to
unique work rate, mask, and gender situations that might apply in a specific
workplace. Use of system default values, which were selected to represent
respirator wear with medium cartridge resistance at a low-moderate work rate,
will allow inter-test comparison of the respirator fit. (3)
The individual who conducts the CNP fit testing shall be thoroughly trained
to perform the test. (4)
The respirator filter or cartridge needs to be replaced with the CNP test
manifold. The inhalation valve downstream from the manifold either needs to
be temporarily removed or propped open. (5)
The test subject shall be trained to hold his or her breath for at least 20
seconds. (6)
The test subject shall don the test respirator without any assistance from
the individual who conducts the CNP fit test. (7)
The QNFT protocol shall be followed according to section I.C.1 except that
the CNP test exercises shall be used. (b)
CNP Test Exercises -- (1) Normal breathing. In a normal
standing position, without talking, the subject shall breathe normally for 1
minute. After the normal breathing exercise, the subject needs to hold head
straight ahead and hold his or her breath for 10 seconds during the test measurement. (2)
Deep breathing. In a normal standing position, the subject shall
breathe slowly and deeply for 1 minute, taking caution not to hyperventilate.
After the deep breathing exercise, the subject needs to hold head straight
ahead and hold his or her breath for 10 seconds during test measurement. (3)
Turning head side to side. Standing in place, the subject shall slowly
turn his or her head from side to side between the extreme positions on each
side for 1 minute. The head shall be held at each extreme momentarily so the
subject can inhale at each side. After the turning head side to side
exercise, the subject needs to hold head full left and hold his or her breath
for 10 seconds during test measurement. Next, the subject needs to hold head
full right and hold his or her breath for 10 seconds during test measurement. (4)
Moving head up and down. Standing in place, the subject shall slowly
move his or her head up and down for 1 minute. The subject shall be
instructed to inhale in the up position (i.e., when looking toward the
ceiling). After the moving head up and down exercise, the subject needs to
hold head full up and hold his or her breath for 10 seconds during test
measurement. Next, the subject needs to hold head full down and hold his or
her breath for 10 seconds during test measurement. (5)
Talking. The subject shall talk out loud slowly and loud enough so as
to be heard clearly by the test conductor. The subject can read from a
prepared text such as the Rainbow Passage, count backward from 100, or recite
a memorized poem or song for 1 minute. After the talking exercise, the
subject needs to hold his or her head straight ahead and hold his or her
breath for 10 seconds during the test measurement. (6)
Grimace. The test subject shall grimace by smiling or frowning for 15
seconds. After the grimace exercise, the subject needs to hold his or her
head straight ahead and hold his or her breath for 10 seconds during the test
measurement. (7)
Bending Over. The test subject shall bend at the waist as if he or she
were to touch his or her toes for 1 minute. Jogging in place shall be
substituted for this exercise in those test environments such as shroud type
QNFT units that prohibit bending at the waist. After the bending over
exercise, the subject needs to hold his or her head straight ahead and hold
his or her breath for 10 seconds during the test measurement. (8)
Normal Breathing. Remove and re-don the respirator within a one-minute
period. Then, in a normal standing position, without talking, the subject shall
breathe normally for 1 minute. After the normal breathing exercise, the
subject needs to hold his or her head straight ahead and hold his or her
breath for 10 seconds during the test measurement. After
the test exercises, the test subject shall be questioned by the test
conductor regarding the acceptability of the respirator upon completion of
the protocol. If it has become unacceptable, another model of a respirator
shall be tried. (c)
CNP Test Instrument. -- (1) The test instrument shall have an effective
audio warning device when the test subject fails to hold his or her breath
during the test. The test shall be terminated whenever the test subject
failed to hold his or her breath. The test subject may be refitted and
retested. (2)
A record of the test needs to be kept on file, assuming the fit test was
successful. The record must contain the test subject's name; overall fit
factor; make, model and size of respirator used, and date tested. Part II. Facepiece Fit Checks (Nonmandatory) A.
Positive pressure check. Close off the exhalation valve and exhale
gently into the facepiece. The face fit is considered satisfactory if a
slight positive pressure can be built up inside the facepiece without any
evidence of outward leakage of air at the seal. For most respirators this
method of leak testing requires the wearer to first remove the exhalation
valve cover before closing off the exhalation valve and then carefully
replacing it after the test. B.
Negative pressure check. Close off the inlet opening of the canister
or cartridge(s) by covering with the palm of the hand(s) or by replacing the
filter seal(s), inhale gently so that the facepiece collapses slightly, and
hold the breath for ten seconds. If the facepiece remains in its slightly
collapsed condition and no inward leakage of air is detected, the tightness
of the respirator is considered satisfactory. Appendix C to 1910.1035 -- Ventilation Chart for Isolation Rooms or
Areas (Mandatory) Under
paragraph(d)(5)(vii), the proposed standard requires that when an AFB
isolation room or area is vacated by an individual with suspected or
confirmed infectious TB, the room or area shall be ventilated according to
current CDC recommendations for a removal efficiency of 99.9 % before
permitting employees to enter without respiratory protection. The following
appendix is an excerpt of the CDC recommendations of the air changes per hour
(ACH) and time in minutes required for removal efficiencies of 90 %, 99 % and
99.9 % of airborne contaminants (Ex.4B). This table specifies the time
necessary to ventilate an isolation room or area, for a given air change per
hour, before allowing employees to enter without respiratory protection. Minutes required for a removal efficiency of:
This
table has been adapted from the formula for the rate of purging airborne
contaminants. (Ex. 5-100) Values have been derived from the formula t1
= [In (C2 + C2) + (Q + V)] x 60, with t1 = 0
and C1 + C2 -- (removal efficiency + 100), and where: t1
= initial timepoint C1
= initial concentration of contaminants C2
= final concentration of contaminants Q=
air flow rate (cubic feet per hour) V
= room volume (cubic feet) Q
+ V = ACH The
times given assume perfect mixing of air within the space (i.e., mixing
factor = 1). However, perfect mixing usually does not occur, and the mixing
factor could be as high as 10 if air distribution is very poor (Ex. 5-99). The
required time is derived by multiplying the appropriate time for the table by
the mixing factor that has been determined for the booth or room. The factor
and required time should be included in the operating instructions provided
by the manufacturer of the booth or enclosure, and these instructions should
be followed. Appendix D to 1910.1035 -- Ultraviolet Radiation Safety and Health
Provisions (Nonmandatory) This
appendix sets forth non-mandatory guidelines on safety and health provisions
concerning the use of ultraviolet germicidal irradiation (UVGI). Because the
effectiveness of UVGI systems will vary, and the interaction of factors such
as humidity, UV intensity, duration of exposure, lamp placement, and air
mixing have not been adequately evaluated, employers may choose to use UVGI
systems as supplements to the administrative, engineering, and work practice
controls required by this standard. OSHA does not consider UVGI as a
substitute or replacement for: (1)
Negative pressure; (2)
Exhaust of contaminated air directly to the outside away from intake vents
and employees; (3)
High efficiency particulate air (HEPA) filtration of contaminated air before
being recirculated to the general facility or exhausted directly outside
(permitted only when it cannot be safely discharged). UVGI
Systems The
intent of UVGI systems is to kill or inactivate airborne microorganisms,
including M. tuberculosis. Two types of systems are generally employed
for this purpose: duct irradiation systems, and upper room air irradiation
systems. (Floor level UVGI systems are used in some laboratory facilities,
but are not specifically discussed in this appendix.) UVGI systems utilize
low-pressure mercury vapor lamps that emit radiant energy predominantly at a
wavelength of 254 nanometers (nm). In duct irradiation systems, one or more
UV tubes are positioned within a duct to irradiate air being exhausted from a
room or facility. In upper room air irradiation systems, UV lamps are suspended
from a ceiling or mounted on a wall. The lamps are positioned such that air
in the upper part of the room is irradiated. The intent is to minimize the
levels of UV radiation in the lower part of the room where the occupants are
located. These systems rely on air mixing to move the air from the lower
portion of the room to the upper portion of the room where it can be
irradiated. Safety
and Health Considerations UV
radiation at 254 nm is absorbed by the outer surfaces of the eyes and skin. Overexposure
to UVGI can result in photokeratitis (inflammation of the cornea) and/or
conjunctivitis (inflammation of the conjunctiva). Keratoconjunctivitis is a
reversible condition but can be debilitating while it runs its course. Because
there is a latency period before health effects are observed, workers may not
recognize this as an occupational injury. Symptoms may include a feeling of
sand in the eyes, tearing, and sensitivity to light. Overexposure of the skin
to UVGI also can result in erythema (reddening). This effect is also
reversible, with recovery occurring within 2 to 3 days. In
1992, the International Agency for Research on Cancer (IARC) classified UV-C
radiation as "probably carcinogenic to humans (Group 2A)". This
classification was based on studies suggesting that UV-C radiation can induce
skin cancers in animals, DNA and chromosome damage in human cells in vitro,
and DNA damage in mammalian skin cells in vivo. In the animal studies,
exposure to UV-B could not be excluded; however, the observed effects were
greater than expected for UV-B alone. Laboratory studies have shown that UV
radiation can activate human immunodeficiency virus (HIV) gene promoters in
human cells (genes in HIV that prompt replication of the virus); however, the
implications of these findings for humans exposed to UVGI are unknown. Occupational
Exposure Criteria for Ultraviolet Radiation In
1972, the National Institute for Occupational Safety and Health (NIOSH)
published a recommended exposure limit (REL) for UV radiation to prevent
adverse effects on the eyes and skin. The NIOSH REL for UV radiation is
wavelength dependent because different wavelengths of ultraviolet radiation
have differing abilities to cause skin and eye effects. The American
Conference of Governmental Industrial Hygienists (ACGIH) also has a Threshold
Limit Value for UV radiation that is identical to the REL in this spectral
region. It should be noted that photosensitive individuals and those
concomitantly exposed to photosensitizing agents (including certain
medications) may not be protected by these occupational exposure limits. The
term relative spectral effectiveness is used to compare UV sources with a
source producing UV radiation only at 270 nm, the wavelength of maximum
sensitivity for corneal injury. For example, the relative spectral
effectiveness (Sl) at 254 nm is 0.5; therefore,
twice as much energy is required at 254 nm to produce the same biological
effect at 270 nm. Thus, at 254 nm, the NIOSH REL is 0.006 joules per square
centimeter (J/cm2), and at 270 nm it is 0.003 J/cm2. For
germicidal lamps, proper use of the REL (or TLV) requires that the measured irradiance
level (E) in microwatts per square centimeter (µW/cm2) be
multiplied by the relative spectral effectiveness at 254 nm (0.5) to obtain
the effective irradiance (Eeff). The maximum permissible exposure
time (t) for workers with unprotected eyes and skin can then be read directly
from Table 1 for selected values of Eeff, or can be calculated (in
seconds) by dividing 0.003 J/cm2 (the NIOSH REL at 270 nm) by Eeff
in W/cm2. To protect workers who are exposed to germicidal UV
radiation for eight hours per day, the measured irradiance (E), should be >0.2
µW/cm2. This is calculated by using Table 1 to obtain Eeff
(0.1 µW/cm2), and then dividing by Sl (0.5). Example:
If the measured irradiance was 0.4 µW/cm2, then the maximum
permissible exposure time is 15,000 seconds, or approximately 4 hours as
shown below:
(For
Maximum Permissible Exposure Times for Selected Values Table, see printed
copy) Measurement Equipment. A UV radiometer can be used to measure the irradiance levels in the
room and to document lamp output. Some UV measurement systems rely on the use
of a detector or probe which is most sensitive at 254 nm, while others rely
on the use of a broad-band radiometer with an actinic probe. The latter
instrument has a response that accounts for the wavelength dependence of the
REL, allowing direct measurement of the effective irradiance(eff).11 While both types of systems are
acceptable, persons performing the measurements should be aware of the
differences so that the measurements obtained are appropriately compared with
the recommended occupational exposure limits. Equipment used to measure UV
radiation should be maintained and calibrated on a regular schedule, as
recommended by the manufacturer. UVGI
Safety and Health Program Employers
should consult with persons having expertise in industrial hygiene,
engineering, and/or health physics before designing and installing UVGI
systems. In addition, the following guidelines should be used to protect
workers from overexposure to UV radiation. These guidelines should be
incorporated into a UVGI safety and health program. One person should be
given responsibility for managing the program. (1)
Exposure Monitoring a.
Upper Air Irradiation Systems. Before an upper air UVGI system is
activated in the workplace, exposure monitoring should be conducted to
determine the levels of UV radiation in the room. The UV radiation levels
will be affected by the position of the lamp, fixture design (including
presence and position of baffles and louvers), tube type, room dimensions,
and presence of UV absorbing or reflecting materials. At a minimum, UV
radiation measurements should be made with the detector directly facing the
lamp at head or eye height (with maximum levels recorded), to assess the
potential UV exposure to the eyes, the most sensitive organ. Because workers
typically move around a room or area while performing their duties, it is
often not possible to predict how long a worker will be in a given location,
nor is it practical to attempt to control exposures administratively by
limiting the duration of exposure at a given location. Therefore, the
exposure monitoring should be conducted in representative locations to
adequately assess the range of potential worker exposures. Worker exposures
should be maintained below the NIOSH REL and ACGIH TLV for ultraviolet radiation. UV
radiation measurements should be made: (1) at the time of initial
installation of the UVGI system; (2) whenever new tubes are installed; and
(3) whenever modifications are made to the UVGI system or to the room that
may affect worker exposures (i.e., adjustment of fixture height, location, or
position of louvers; addition of UV absorbing or reflecting materials; and
changes in room dimensions). UV
radiation measurements may also be obtained to document the UV output of the
lamp for tube replacement or other purposes. Because these types of
measurements are commonly done close to the source of the UV output, the
person obtaining the measurements may be exposed to high levels of UV
radiation. UV radiation levels up to 840 µW/cm2 (420 µ/cm2
effective irradiance) have been measured at a distance of four inches from
the face of a 30W tube that had been in use several months. Using the NIOSH
REL, this exposure level would result in a permissible exposure time of only
7 seconds for workers with unprotected eyes and skin. Because of the high
irradiance levels, it would not be practical in this situation to control UV
exposures by limiting exposure duration. Skin and eye protection would be
needed to protect the worker when making UV measurements close to the source. b.
Duct Irradiation Systems. Duct irradiation systems frequently involve
the placement of several UV tubes within a section of duct work. Thus,
workers who have contact with these lamps are potentially exposed to high
levels of UV radiation. This presents a hazard for maintenance workers and
others who are responsible for documenting the UV output of these lamps. At
one facility where a duct irradiation system was used, UV radiation levels up
to 950 µW/cm2 were measured at a distance of approximately three
feet from a bank of four 39W UV tubes. In this situation, the NIOSH REL would
be exceeded in about 6 seconds; therefore, skin and eye protection would be
needed to prevent worker overexposures to UV radiation. Most UV exposures
resulting from duct irradiation systems can be avoided by inactivating the
lamps before maintenance work is done, and providing an access port for
viewing the lamps during preventive maintenance inspections. These control
measures are discussed further in the Control Methods section of this
appendix. (2)
Control Measures The
following control measures should be used to prevent or reduce UV exposures. a.
Engineering Controls. 1. In upper air irradiation systems, the UV
tubes in the fixture should not be visible from any usual location/position
in the room. The fixtures should contain baffles or louvers that are
appropriately positioned to direct the UV irradiation to the upper air space.
The baffles and louvers should be constructed so that they cannot be easily
bent or deformed. 2.
In upper air irradiation systems, all highly UV reflecting material should be
removed, replaced, or covered. Reflectance values for various materials have
been published. Etched aluminum and chromium are examples of materials that
have high reflectance values (88 and 45 % reflectance, respectively) for 254
nm radiation. Unpainted white wall plaster is reported to have reflectance
values of 40-60 %. 3.
UV-absorbing paints (such as those containing titanium dioxide) can be used
on ceilings and walls to minimize reflectance of UV in the occupied space, as
needed. 4.
The on/off switch for the UVGI lamps should not be located on the same switch
as the general room lighting. In addition, these switches should be
positioned in such a location that only authorized persons have access to
them and they should be locked to ensure that they are not accidentally
turned on or off. 5.
In duct irradiation systems, there should be an access panel for conducting
routine maintenance, monitoring, and cleaning. This access panel should have
an interlock or other device to ensure that the tubes are deactivated
whenever the panel is opened. To prevent unnecessary UV exposures to
maintenance personnel, this port should have a window for viewing the tubes
during routine inspections. Ordinary glass (not quartz) and plastics
(polycarbonate and polymethylmethacrylate) are sufficient to filter out the
UV radiation. 6.
All UVGI systems should be inactivated prior to maintenance activity in the
affected areas, such as when maintenance workers replace lamps or when
entering the upper air space for room maintenance, renovation, or repair
work. b.
Personal Protective Equipment. UV exposures should be maintained below
existing recommended levels. Despite the use of the engineering controls
listed above, there may be situations when worker exposures exceed the NIOSH
REL, such as when UV measurements are being made close to the lamp source in
order to document lamp output, or when maintenance procedures must be
performed in areas where UVGI systems are activated. In these and other
situations where the NIOSH REL is exceeded, personal protective equipment is
needed to prevent worker overexposure to UV radiation. This includes the use
of UV-absorbing eyewear with side-shields, head, neck, and face covering
opaque to UV radiation, gloves, and long-sleeved garments. The weave of the
fabric has been shown to be the major factor affecting transmission of UV
radiation, thus, tightly woven fabrics are recommended. UV-absorbing
sunscreens with solar-protection factors of 15 or higher may help protect
photosensitive persons. (3)
Labeling Warning
labels should be placed on UV lamp fixtures in upper air irradiation systems
and on access panels in duct irradiation systems to alert workers and other
room occupants to this potential hazard. These warning labels should be of
sufficient size to be visible to room occupants and should be in the
appropriate language(s). Examples of warning labels are shown below:
(4)
Training All
workers who have potential exposure to UV radiation from UVGI systems should
be receiving training on the hazards, relevant symptoms, and precautions
concerning exposure. This training should include specific information on: a.
The rationale for use of UVGI and general principles of operation, including
its limitations; b.
Control measures used to prevent or reduce UV radiation exposure; c.
Health effects associated with overexposure to UV radiation (including the
potential for additive exposure from other UV sources, such as solar radiation
and welding); d.
Recognition of the symptoms of eye and skin damage; and e.
Special precautions to be taken by workers to prevent overexposure to UV
radiation (including the use of personal protective equipment). (5)
Medical Recommendations The
worker's medical history should be obtained to determine if the worker
suffers from any condition that may be exacerbated by exposure to UV
radiation. Workers should be advised that any eye or skin irritation that
develops after acute exposure to UV radiation, or any skin lesion that
appears on skin repeatedly exposed to UV radiation should be examined by a
physician. (6)
Recordkeeping The
employer should maintain accurate and complete records pertaining to the
following: a.
Exposure monitoring; b.
Instrument calibration; c.
Documentation of health effects; d.
Training; e.
Maintenance of UVGI systems, including cleaning and replacement of tubes. References 1. IES [1966]. Illuminating Engineering Society
(IES) lighting handbook, 4th ed., IES, New York, 25-27. 2. NIOSH [1972]. Criteria for a recommended
standard . . . occupational exposure to ultraviolet radiation. U.S.
Department of Health, Education, and Welfare, Public Health Service, Health
Services and Mental Health Administration, National Institute for Occupational
Safety and Health, Washington, DC, HSM-11009. 3. IARC [1992]. IARC monographs on the
evaluation of carcinogenic risks to humans: solar and ultraviolet radiation. Vol.
55. Lyon, France: World Health Organization, International Agency for
Research on Cancer. 4. Valerie K, Delers A, Bruck C, Thiriart C,
Rosenberg H, Debouck C, Rosenberg M [1988]. Activation of human
immunodeficiency virus type 1 by DNA damage in human cells. Nature 333:78-81. 5. Zmudzka BZ, Beer
JZ [1990]. Activation
of human immunodeficiency virus by ultraviolet radiation (yearly review). Photochem
and Photobiol, 52:1153-1162. 6. Wallace BM, Lasker JS [1992]. Awakenings . .
. UV light and HIV gene activation. Science, 257:1211-1212. 7. Valerie K,
Rosenberg M [1990]. Chromatin
structure implicated in activation of HIV-1 gene expression by ultraviolet
light. The New Biologist, 2:712-718. 8. Stein B,
Rahmsdorf HJ, Steffen A, Litfin M, Herrlich P [1989]. UV-induced DNA damage is an
intermediate step in UV-induced expression of human immunodeficiency virus
type 1, collagenase, C-fos, and metallathionein. Mol Cell Biol, 9:5169. 9. Clerici M, Shearer GM [1992]. UV light
exposure and HIV replication. Science, 11/13/92:1070-1071. 10. ACGIH [1994]. 1994-1995 Threshold limit
values for chemical substances and physical agents and biological exposure
indices. American Conference of Governmental Industrial Hygienists,
Cincinnati, OH: ACGIH. 11. Murray WE [1990]. Ultraviolet radiation
exposures in a mycobacteriology laboratory. Health Physics, 58(4):507-510. 12. NIOSH [1992]. Hazard evaluation and
technical assistance report: Onondaga County Medical Examiner's Office,
Syracuse, New York. Cincinnati, OH: U.S. Department of Health and Human
Services, Public Health Service, Centers for Disease Control and Prevention,
National Institute for Occupational Safety and Health, (NIOSH Report No. HETA
92-171-2255). 13. Summer W [1962]. Ultra-violet and infra-red
engineering. New York: Interscience Publishers, p 300. 14. Sliney DH, Wolbarsht ML [1982]. Safety with
lasers and other optical sources. 3rd Printing. New York: Plenum Press. 15. Gies HP, Roy CR, Elliott G [1994].
Ultraviolet radiation protection factors for clothing. Health Physics
67(2):131-139. 16. CDC [1994]. Guidelines for preventing the
transmission of tuberculosis in health-care facilities, second edition. Atlanta,
GA: Centers for Disease Control and Prevention. Appendix E to 1910.1035 -- Performance Monitoring Procedures for HEPA
Filters (Nonmandatory) This
appendix offers nonmandatory guidance on design considerations and
performance monitoring of HEPA filters used in air systems that carry air
that may reasonably be anticipated to contain aerosolized M. tuberculosis
(e.g., recirculation into building circulating air system, exhausting
outdoors near air intakes, etc.). Both
OSHA and CDC recommend against the recirculation of air that may reasonably
be anticipated to contain aerosolized M. tuberculosis into the general
circulating air system of the building or other opportunities where such air
may become entrained into the circulating air system (e.g., outdoor
exhausting near intakes, transfer to heat wheels, etc.). When recirculation
is unavoidable, the air should be cleaned with HEPA filtration. In order to
assure effective functioning of these systems, they should be properly
designed, installed, and maintained. Design
of HEPA Filtration Systems The
following elements should be considered for incorporation into the design of
HEPA filtration systems: 1.
Provide upstream prefiltering to reduce dust that may plug the HEPA filter. 2.
Provide worker-entry into housings for visual examinations and probe scanning
for leaks of filter media and frame-to-filter interfaces. In addition,
adequate access should be provided to allow for replacement of the HEPA
filters and pre-filters without contaminating the work area by unintentional
jarring or dropping of the filters. 3.
Provide devices for measuring HEPA filter loading (e.g., pressure
differential across a filter). 4.
Provide appropriate mounting frames and seals to minimize frame-to-filter
leakage. 5.
Specify filter media to match operating criteria (e.g., face velocity,
volumetric flow rate, pressure drop, etc.). 6.
Design upstream and downstream duct to facilitate performance monitoring (e.g.,
good air mixing for uniform dispersal of challenge aerosols, sectioning to
allow isolation of leaks, etc.). 7.
HEPA filters must operate in dry airstreams. Tests have shown that exposure
to high humidity for a period of five hours will result in a threefold
increase in particle penetration. Maintenance
of HEPA Filtration Systems HEPA
filtration systems are generally passive systems without moving parts, so the
majority of filter maintenance activities are associated with performance
monitoring. In terms of performance monitoring, HEPA filters are to be
monitored for filter loading and for possible leakage every 6
months, whenever filters are changed, and more often if necessary to maintain
effectiveness. Leaks in HEPA filters can occur in the following ways: (1) in
the filter media, (2) in the bond between media and frame, (3) in the frame
gasket, (4) in the support frame, and (5) in between the frame and the wall. Testing
of HEPA filters after installation is used to detect leaks associated with
shipping damage and with installation problems such as handling damage,
variations in gasket thickness and poorly formed gasket corners. Periodic
testing detects deterioration of components, relaxation of gaskets, clamping
devices, weld cracks or other leaks that may develop during use. This
deterioration will take place even if the system is not on-line and in use. Monitoring
for Filter Loading HEPA
filtration systems become loaded with particulate matter through use. Although
this loading improves particulate arrestance, it eventually increases the
pressure drop across the filter assembly. Consequently, the flow capacity
begins to diminish and bypass leakage at the frame-to-filter interface
increases. Therefore, these filters need to be monitored and changed. It
is imperative that the differential pressures across the HEPA filter remain
below the maximum operating resistance level set by the manufacturer and
stamped on the filter label. Filter penetration by contaminants can occur
when HEPA filters exceed the manufacturer's maximum resistance rating, making
the system ineffective. The
operating resistance level is determined by measuring the pressure
differential across the filter through use of a pressure sensing device. Measurements
of differential pressure across the HEPA filters should be made when the
prefilters have been removed. These measurements should be used to predict
future HEPA filter replacement or for determining the need for immediate HEPA
filter replacement. Additional control measures can be used to detect a
differential pressure that exceeds the maximum operating resistance which
signals the alarm's set point (i.e., audible/visual alarms or computerized
error messages). All
pressure measurements should be logged and retained in accordance with
paragraph (i)(4)(ii) of this standard. Monitoring
for In-service Filter Leakage In
CDC's "Guidelines for Preventing the Transmission of Mycobacterium
tuberculosis in Health-Care Facilities" [Ex. 4B], the di-octal
phthalate (DOP) penetration test as described in Chapter 25 of the 1992 Systems
Handbook from the American Society of Heating, Refrigerating and
Air-Conditioning Engineers (ASHRAE) is offered as a method of performance
monitoring HEPA filters. The basis of this well-recognized test is to
challenge a HEPA filter assembly with a uniformly distributed cloud of 0.3 µm
(mass median diameter) DOP aerosol and measure the DOP smoke upstream and
downstream with a light-scattering photometer. Penetration "P"
through the filter assembly is the performance criterion typically specified
and is defined as:
Penetration
is related to filter efficiency "E" by the equation: E=100(1-P)
% Therefore,
an efficiency of 99.97 % is equivalent to P=0.0003. Other
Filter Testing Methods There
are many recognized HEPA filter testing standards. Most of these standards
utilize DOP aerosol to challenge the HEPA filters and provide penetration
performance data for 0.3 µm size particles. Since TB droplet nuclei range in
size from 1 to 5 µm, the DOP aerosol challenge is indicative of droplet
nuclei penetration. Some manufacturers may provide bench test data for
filtration efficiency versus particle size which may be useful information
when selecting filters but may be difficult to duplicate in the field for
in-service testing. These test standards include: 1.
Standard UL 586, High-Efficiency, Particulate, Air Filter Units as
published by Underwriters Laboratories, 1990 (Ex. 7-227). This test is
designed for bench testing at the factory and does not include the
frame-to-filter bypass leakage measured by in-service testing. This test
method uses a light beam-photocell combination (photometer) to measure the
density of the DOP smoke in the air. 2.
Standard ASTM F1471-92, Air Cleaning Performance of a High-Efficiency
Particulate Air-Filter System, as published by the American Society for
Testing and Materials, 1993 (Ex. 7-222). This test can be used in the field
for in-service testing of HEPA filters. This test method utilizes a laser
aerosol spectrometer which can count particles by particle size. 3.
Standard NSF-49, Appendix B, HEPA Filter Leak Test for Biosafety Cabinets,
as published by the National Sanitation Foundation (Ex. 7-226). This test is
designed for in-service HEPA filter testing and utilizes a portable
photometer probe which can be passed over the filter frame perimeter to check
for bypass leaks. Unfortunately,
there are hazards associated with exposure to DOP. The Material Safety Data
Sheet for DOP reports irritation, nausea and numbness as symptoms associated
with DOP inhalation. Nausea, diarrhea, reproductive effects, liver
enlargement, and cancer are effects associated with ingestion of DOP. Therefore,
performance testing that does not utilize DOP should also be considered. Alternative
methods are in use and being developed that capitalize on recently developed
optical particle counters (e.g., lasers) that can count particles at
specified sizes. For example, the National Environmental Balancing Bureau
(NEBB) publishes Procedural Standards for Certified Testing of Clean
rooms' Section 8.3 presents an Ambient Particle Aerosol Challenge Method
that utilizes new-generation optical particle counters to measure upstream
and downstream concentrations of particles of a specified size (Ex. 7-228). Only
ambient air is measured and no aerosol is generated. This method may have
merit for TB applications because ambient air has a statistically significant
quantity of particles less than 3.0 µm, but at the same time, this high
number of particles may overload the instrument. Because
a dark DOP smoke is not required to attenuate light as is the case with a
photometer, recently developed optical particle counters offer the
opportunity for an alternative non-toxic challenge aerosol like that
described in the proposed Standard 52.2 Method of Testing General
Ventilation Air-Cleaning Devices for Removal Efficiency by Particle Size
from the American Society of Heating, Refrigerating and Air-Conditioning
Engineers. This non-toxic challenge aerosol is based upon potassium chloride
(KC) particles which are generated in the 0.3 to 10 µm size range (Ex.
7-224). Filter
Testing Performance Criteria The
following should be considered when setting performance testing criteria: (1)
Failure of a HEPA filter in a recirculating air system can have serious
consequences; (2) HEPA filters are more efficient in removing droplet nuclei
than DOP due to the larger particle size of droplet nuclei; (3) In-service
filter penetration testing should match factory testing that is P < 0.0003
for 0.3µm challenge particle; (4) The differential pressure drop across a
HEPA filter from dirt loading should never exceed the maximum operating
resistance set by the manufacturer and stamped on the filter label; (5)
Penetration should not exceed 0.0001 when performing localized penetration
scanning with a photometer probe around filter frames and across the filter
face. Appendix F to 1910.1035 -- A Guide to Writing an Exposure Control Plan
(Non-mandatory) A
Guide to Writing an Exposure Control Plan is a non-mandatory appendix
developed to assist employers in complying with § 1910.1035 Occupational
Exposure to Tuberculosis. This standard requires employers to have a written
Exposure Control Plan (ECP) documenting procedures they use to control
exposure to Tuberculosis (TB). The
following guide aids employers in writing the required ECP by reviewing the
standard's requirements and providing examples of policy, narrative
statements, and a "fill-in-the-blank" sample ECP. Before using this
guide, employers will need to read the standard. Once familiar with the
standard, they can use this appendix to develop a program specific to their
facility. Employers
are not required to use the sample ECP included in this guide. They may
develop their own format and may include the TB ECP in their overall
infection control plan. However, the ECP must include all OSHA required
information and all policies and procedures in the plan must be implemented
whether the ECP is a separate plan or included in another document. If the TB
elements are included in an overall infection control plan, the employer must
develop an index referring the reader to their locations within that plan. Since
the elements in the sample ECP are the minimum necessary to meet the
standard's requirements, employers may enhance the sample with more
comprehensive procedures if they wish. OSHA
developed the guide to help employers comply with the standard. The
information contained in this Guide to Writing an Exposure Control Plan for
Occupational Exposure to Tuberculosis is not considered to be a substitute
for the OSH Act or any provisions of the OSHA Standard. It provides general
guidance for a particular standards-related topic and should not be
considered a legal authority for compliance with OSHA requirements. The
reader should consult the OSHA standard in its entirety for specific
compliance requirements. Employers
who have additional questions concerning this standard may contact the
nearest OSHA office. How to Use This Guide A
Guide to Writing An Exposure Control Plan has two components: Notes to the
Employer and a Sample Exposure Control Plan. Notes to the Employer consists
of explanations for some of the standard's ECP requirements, guidance about
writing an ECP and information about practices common to a variety of
employers. Notes to the Employer is organized to correspond chronologically
to the Sample Exposure Control Plan. The
Sample Exposure Control Plan contains examples of policy statements and
procedures. It has a number of sections and is organized in program
development form. Although it does not always follow the exact sequence of
the standard, all elements of the standard are included. Each section of the
Sample ECP is cross-referenced to the specific provisions of the standard
using the letter and numerical paragraph designation. The Sample ECP has
blank spaces to be completed by the employer with site-specific information. The
standard provides a tiered approach to compliance. Not all provisions apply
to all facilities. This approach accommodates facilities with varying
factors. OSHA's sample ECP accommodates the difference between these types of
facilities. (1)
The first tier is employers (other than the operators of a laboratory) that
do not admit or provide medical services to individuals with suspected or
confirmed infectious TB, have had no cases of confirmed TB in the past 12
months and are located in counties that in the past two years have had zero
cases of confirmed infectious TB in one year and fewer than 6 cases of
confirmed infectious TB in the other year. Work settings in this tier have
presented minimal occupational exposure and therefore may choose to comply
with only a limited number of provisions. (See Appendix A). Required elements
for these facilities are underlined in the sample ECP. They include:
procedures for exposure determination, prompt identification of individuals
with suspected or confirmed infectious TB, exposure incident reporting, and
procedures for referring individuals with suspected or confirmed TB to
facilities with appropriate isolation capabilities. Employers
who wish to have a minimal exposure control plan as described in Appendix A
must document the number of cases of tuberculosis reported in their county in
the previous twelve month reporting period and the number of individuals with
confirmed tuberculosis encountered in the facility in the previous twelve
months. (2)
The second tier encompasses employers who use early identification and
transfer procedures rather than admit individuals with suspected or confirmed
infectious TB. They typically do not have AFB isolation rooms or autopsy
rooms or conduct high-hazard procedures in their facility. These facilities
can omit the sections about AFB isolation rooms and engineering controls
since these provisions do not apply to them unless they have to use
temporarily isolate when it is not possible to transfer individuals with
suspected or confirmed infectious TB within five hours. Paragraph (c)(2)(ii)
lists the requirements of the ECP for this type of facility. In the sample
ECP, certain sections are starred (*) to assist facilities that transfer
individuals with suspected or confirmed infectious TB within five hours of
discovery. These employers may omit the starred sections when writing their
ECP. (3)
The third tier covers employers who admit and provide medical services to
individuals with suspected or confirmed infectious TB. These employers are
required to have AFB isolation rooms and procedures to protect employees
working in or around those rooms. In addition, they must have maintenance
schedules for engineering controls as well as other protections. Paragraph
(c)(2)(iii) lists specific requirements for these facilities. However, if
these employers transfer some individuals with suspected or confirmed
infectious TB as well as admit and provide medical services for those
individuals, the facility must have procedures for the transfer. The sample
ECP includes all required ECP elements thus providing guidance to facilities
that admit and provide medical services. Sample Exposure
Control Plan Notes to the Employer Policies
and Program Administration The
standard requires each employer to have a written exposure control plan and
to review and update it annually. The Sample Exposure Control Plan has
examples of statements reflecting the employer's policy. Blanks are provided
for the employer to designate the facility name. Employers
have limited ECP provisions (see Appendix A) if they (1) do not admit or
provide medical services to individuals with suspected or confirmed
infectious TB, (2) have had no case of confirmed infectious TB in the past 12
months and (3) are located in a county that, in the past 2 years, has had
zero cases of confirmed infectious TB reported in one year and fewer than 6
cases of confirmed infectious TB reported in the other year. (Paragraph (b)).
In addition, these employers must determine the number of reported cases in
the county for the last twelve month reporting period and record it in the
ECP. They must also document the number of confirmed cases of TB in their
facilities. The numbers can be recorded in this first section of the ECP. The
written ECP must be accessible to employees, OSHA and NIOSH representatives
for viewing and copying as necessary. (Paragraph (c)(2)(vii)) A sample
statement regarding the accessibility is written below. OSHA does not require
this statement to be written. However, employers may include this type of
statement in their ECP to clearly define the company's/organization's policy. Sample
Statement: Employees and/or OSHA or NIOSH representatives may view the ECP at
________ (location of ECP)________ and may copy the plan as necessary. Designating
a specific person to be responsible for maintaining the exposure control plan
is not a requirement of the regulation. However, it is a common practice. Sample
Statement: ________ (responsible person/department) ________ is responsible
for maintaining, reviewing and updating the Exposure Control Plan (ECP). Employee
Exposure Determination (Paragraph (c)(1)(i)(A)) In
paragraph (c)(1)(i) & (ii), OSHA requires employers to review job
classifications in their facilities and determine which employees have
occupational exposure to infectious TB (Occupational exposure is defined in
paragraph (j) of the standard). All TB exposure determinations must be made
without regard to the use of respiratory protection. There
are two basic employee job classifications for employers to consider: (1)
jobs in which all employees have occupational exposure to infectious
tuberculosis because of the very nature of the job such as respiratory
therapists and nurses who work on a pulmonary unit and (2) jobs that result
in occupational exposure to tuberculosis when certain tasks or procedures are
performed; for example, dietary personnel delivering meals to an individual
in AFB isolation or housekeeping staff cleaning an AFB isolation room. All
employees in the first job classification are considered to have occupational
exposure to infectious TB, so specific job tasks for this classification are
not required to be defined. In the second category, however, only some
employees may have occupational exposure and , then, only when performing
certain tasks. Therefore, OSHA requires the employer to define those tasks. Examples
of tasks in which employees may have occupational exposure to TB include:
transporting patients; entering occupied isolation areas to clean or deliver
meals; performing maintenance on HVAC systems that exhaust air from occupied
AFB isolation rooms; and, performing suctioning and/or aerosolized treatments
on patients with suspected/confirmed TB. Tasks may be listed in closely
related groups or as individual tasks. Not
all employers have both types of job classifications. Employers are not required
to complete both categories unless there are job classifications that pertain
to each. Employee
Notification of TB Hazards (Paragraph (c)(2)(i)(B)) The
standard requires that the employer include procedures in the ECP "for
providing information about individuals with suspected or confirmed
infectious TB or about air that may reasonably be anticipated to contain
aerosolized M. tuberculosis to occupationally exposed employees who
need this information in order to take proper precautions." The
employer must assure that employees have enough information to take proper
precautions against exposure to TB. However, the employer must also consider
the medical confidentiality of the infectious individual and assure that this
confidentiality is maintained to the extent possible and consistent with
applicable laws. Employers
are expected to define responsibilities and outline procedures used to inform
employees of TB hazards. OSHA requires that an employer notify employees by
posting signs and labeling ventilation ducts. (Paragraphs (h) (1) & (2)) The
following sample statements provide an abbreviated example of some procedures
that might be used in a health care facility. These statements are not OSHA
requirements but examples. Sample Statement: As soon as infectious TB is suspected the nurse in charge of the unit
must be informed. The nurse in charge of the unit also must assure that (1)
the individual is placed in an AFB isolation room marked with a sign:
"No Admittance Without Wearing a Type N95 of More Protective
Respirator", (2) the nursing supervisor and infection control specialist
are notified, (3) all staff working on the unit are notified, and (4) proper
equipment is obtained. If
the individual with suspected or confirmed infectious TB must be transferred to
be placed in an isolation room, all procedures required by this ECP will be
utilized, such as masking the individual or if that cannot be done, having
the employee don a respirator. The
nurse in charge of the unit immediately notifies the facility engineer to
assure that (1) the engineering controls are working properly and (2) all
maintenance and contract employees are informed of the potential TB hazard. ________
(maintenance engineer) ________ is to immediately check to assure that all
ducts carrying exhaust air from the room occupied by the individual with
suspected or confirmed infectious TB are labeled "Contaminated air --
Respiratory Protection Required". Dietary,
laboratory, and other test order sheets are specially noted to indicate
"Respiratory Isolation -- No admittance without an N95 or More
Protective Respirator." In
addition to informing their own employees, host employers are required to
notify contractors of TB hazards. Some contractors and contracting employees
may be required to enter or work in AFB isolation areas or other areas in the
facility where occupational exposure is likely to occur or where air systems
may reasonably be anticipated to contain aerosolized M. tuberculosis. Since
host employers know the location of the hazards, they must inform the
contractor. (Paragraph (d)(6)) OSHA
requires the employer to post signs at the entrance to (1) rooms or areas
used to isolate individuals with suspected or confirmed infectious TB, (2)
areas where procedures or services are being performed on an individual with
suspected or confirmed infectious tuberculosis and (3) clinical/research
laboratories where M. tuberculosis is present. (Paragraph (h)(2)) Signs
must include a picture of a stop sign, have a red background with white
lettering and say: "No Admittance Without Wearing a N95 or More
Protective Respirator." The employer may include additional language
provided the major message on the sign remains clear. (Paragraph (h)(2)(iii)) After
the room is vacated, the sign must remain posted at the entrance until the
room or area is ventilated, using the USPHS recommendations for removal
efficiency of 99.9 %, for the time necessary to permit entry without the use
of a respirator. See Appendix C of the standard. (Paragraph (h)(2)(ii)) The
room does not need to be ventilated and the sign may be removed immediately
if both of the following criteria are met (1) the room was occupied by an
individual with suspected infectious tuberculosis and (2) that individual is
medically determined to be non-infectious. (Paragraph (h)(2)(ii)) If
employers have engineering controls, those controls must be labeled
appropriately and the labeling procedures must be noted in the ECP. (Paragraph
(h)(1)) The
type of HVAC system in the facility will determine where ducts are labeled. Ducts
that have HEPA filtration must be labeled at all duct access points located
prior to the HEPA filter. HVAC systems that exhaust air directly to the
outside must be labeled at all access points, fans and exhaust outlets. (Paragraph
(h)(1)) Signs
at the entrance to clinical or research laboratories and autopsy suites must
include the biohazard symbol, name of the laboratory director or other
designated responsible person, M. tuberculosis, and special
requirements for entering the laboratory or autopsy room. In addition,
contaminated laboratory wastes must be labeled with the biohazard symbol or
be placed in a red container. (Paragraph (h)(2)(iv)) Although
the standard does not require noting this in the ECP, employers may want to
document where engineering controls are located in their facility. If an
employer chooses to note this, sample verbiage may be: Sample
Statement: ________ (list type of engineering controls in place) ______________________________________________________________________ engineering
controls are used in the Bronchoscopy suite located on the third floor of
this building. OR There
are no high-hazard procedures performed in this facility. There are no
engineering controls in place. Exposure Incident Reporting (Paragraph (c)(2)(i)(C)) The
employer must investigate circumstances surrounding TB Skin Test conversions
and exposure incidents to determine the cause and ways to make changes to
prevent similar occurrences. (Paragraph (g)(4)(iv)) The
procedures used to report and then to evaluate the incident must be included
in this section of the ECP. In addition, employees are required to report
incidents to a particular department or person. (Paragraph (c)(2)(i)(C)) This
information must be included here, also. Sample
Statement: Exposure incidents are to be reported to ________ (name and
department)
._____________________________________________________________________ reporting
procedures utilized at __ (organization's name) __ are: ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Procedures
for evaluating the circumstances surrounding the exposure incident at ______
(organization's name) ________ are: ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Prompt
Identification of Individuals With Suspected or Confirmed Infectious TB
(Paragraph (c)(2)(ii) & (iii)(A)) Each
facility is required to establish procedures for promptly identifying
individuals with suspected or confirmed infectious TB. The standard considers
"suspected or confirmed infectious TB" to be: "A
potential disease state in which an individual is known or with reasonable
diligence should be known, by the employer to have one or more of the
following conditions, unless the individual's condition has been medically
determined to result from a cause other than TB: (1) to be infected with M.
tuberculosis and to have signs and symptoms of TB; (2) to have a positive
acid fast bacilla (AFB) smear; or (3) to have a persistent cough lasting 3 or
more weeks and two or more symptoms of active TB (e.g., bloody sputum,
night sweats, weight loss, fever, anorexia)". (Paragraph (j)) This
definition must be included in the early identification criteria. Although
not mandated by OSHA, some employers add high risk factors like IV drug use,
immunocompromised status, recent immigration from Asia, Africa, Latin
America, etc. Some
employers use the 1994 CDC Guidelines for Preventing the Transmission of
Mycobacterium Tuberculosis in Health-Care Facilities to assist in early
identification of TB (Ex. 4). These guidelines state, "TB is not
distributed evenly throughout all segments of the U.S. population" and
defines groups known to have a higher prevalence of TB infection. These high
risk groups include "foreign born persons from Asia, Africa, Latin
America and the Caribbean; medically under served populations(e.g.
some African-Americans, Hispanics, Asians, and Pacific Islanders, American
Indians, and Alaskan Natives); homeless persons; current or former
correctional-facility inmates; alcoholics; intravenous drug-users; and the
elderly." Persons with certain medical conditions have a greater risk of
progression from latent infection to active disease. These medical conditions
are defined in the 1994 CDC guidelines as: "HIV infection, silicosis,
diabetes mellitus, gastrectomy or jejuno-ileal bypass, being greater than 10
% below ideal body weight, chronic renal failure or renal dialysis,
immuno-suppression due to drug therapy and some malignancies." There
are several ways to conduct early identification. Many employers use a
questionnaire to quickly assess the individual's health status at intake or
admission. Some employers located in communities considered to have a high
incidence of TB or working with high risk populations use chest x-rays. Since
use of a questionnaire is a common practice, OSHA included one in the Sample
ECP. This is not mandatory but is a guide for those employers who may wish to
develop a questionnaire. An
example of a policy statement referring to use of a questionnaire is: Sample
Statement: ____ (organization's name) ________ uses the attached
questionnaire to assess the individual's health status as related to
suspected or confirmed infectious TB. An individual who has two or more of
the symptoms of Tuberculosis in addition to a prolonged cough, a positive AFB
smear or is known by ____ (organization's name) ________ or any of its
employees to be infected with M. tuberculosis is categorized as having
suspected or confirmed infectious TB. Employers
Who Transfer (Paragraph (c)(2)(ii)) Procedures
for Transfer of Individuals With Suspected or Confirmed Tuberculosis Employers
that transfer rather than admit and provide medical services must document
their procedures for isolating an individual while awaiting transfer such as
segregating and masking the individual and procedures used if the individual
cannot be transferred within 5 hours. This includes documenting the type of
equipment used (e.g. masks, respirators). In
the remainder of the sample ECP, employers who transfer suspected or
confirmed infectious TB within 5 hours of identification may omit starred
sections if they do not have isolation rooms and engineering controls. Employers
who do not admit or provide medical services to individuals with suspected or
confirmed infectious TB, have not encountered any individuals with confirmed
TB in their facility in the past twelve months and who are located in
counties that in the past two years have had zero cases of confirmed TB
reported in one year and fewer than 6 cases in the other year and wish to
claim reduced responsibilities must be prepared to transfer such individuals.
Therefore, the standard requires these facilities to have procedures for
transferring an individual with suspected or confirmed infectious TB, if encountered.
(Appendix A) Employers
Who Admit and Provide Medical Services (Paragraph(c)(2)(iii)) Procedures
for Isolating and Managing Care (Paragraph (c)(2)(iii)(B)) The
employer must document procedures for isolating individuals with suspected or
confirmed infectious TB such as using AFB isolation rooms and procedures for
managing care to minimize employee exposure. Procedures
listed in the Sample ECP are limited to the standard requirements. Employers
should add any other isolation and segregation procedures used in their
facility to assure that their ECP reflects the way they manage isolation and
segregation. Employers
who transfer individuals with suspected or confirmed infectious TB do not
need to include procedures for isolating and managing care. However, as
stated above, they must list procedures for transferring the individual and
segregating and masking these individuals while awaiting transfer. In
addition, employers who do not perform high hazard procedures in their
facilities do not need to notate anything in the high hazard section of the
ECP. These employers may wish to enhance their ECP by clarifying their
functions, however. A sample of a statement to enhance and clarify is: Sample Statement: (1) This facility transfers individuals with suspected or confirmed
infectious TB within 5 hours of identification, (2) high-hazard procedures
are not performed in this facility, (3) there are no engineering controls for
TB control at this facility. Again,
the above statements are not OSHA requirements. Each
employer who admits or provides services to individuals with suspected or
confirmed infectious TB is required to institute policies and procedures to
address the following issues. The procedures in the Sample ECP are an
abbreviated version of the OSHA requirements. (Paragraph (c)(2)(iii)(B) (1
through 5)):
Some
facilities may have extensive procedures while others may have less involved
procedures. The extensiveness of the procedures is determined by the type of
tasks and services provided the individual with suspected or confirmed
infectious TB in that facility. Whatever
the procedures are, the employer is expected to assure that the procedures
comply with the OSHA requirement and that all procedures are implemented. *High-Hazard
Procedures (Paragraph (c)(2)(iii)(C)) The
ECP must contain a list of high-hazard procedures performed in the facility. (*)All
high-hazard procedures that may aerosolize M. tuberculosis must be
performed in an AFB isolation room, an AFB isolation area, or in a special
AFB containment booth. Examples of high hazard procedures include
bronchoscopy, pulmonary function testing, endoscopy and autopsy on an
individual with suspected or confirmed infectious TB. *Engineering
Controls Maintenance Schedules and Records (Paragraph (c)(2)(iii)(D)) Employers
who have engineering controls in any part of their facility must include a
maintenance and performance monitoring schedule in this section of the ECP. (Appendix
E) Sample Statement: Engineering controls for infectious TB are inspected, maintained and
undergo performance monitoring according to the following schedule: ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Clinical
and Research Laboratory Biosafety Procedures Paragraph (c)(2)(iv)) OSHA
requires that the facility's laboratory director determine and document the
biosafety level at which the laboratory operates. In
addition, the laboratory director must determine and document the need for
(1) controlled access, (2) anterooms, (3) sealed windows, (4) directional
airflow, (5) preventing recirculation of laboratory exhaust air, (6)
filtration of exhaust air before discharge to the outside and (7) thimble
exhaust connections for biological safety cabinets. The
laboratory director must consult and follow the guidelines found in the OSHA
regulation. Home
Health Care or Home-Based Hospice Care (Paragraph (c)(2)(v)) OSHA
requires employers of Home Care or Home-based Hospice care to include
procedures for prompt identification of individuals with suspected or
confirmed infectious TB. In addition procedures to minimize employee exposure
to such individuals and a list of any high-hazard procedures performed in the
home and procedures for delaying elective high hazards procedures or surgery
until the individual is non-infectious must be included in the ECP. Sample Exposure Control Plan Exposure
Control Plan (Paragraph(c)(2)) Policies
and Program Administration (company name) maintains, reviews and updates the Exposure Control
Plan (ECP) at least annually, and whenever necessary to reflect new or
modified tasks, procedures and engineering controls * that affect
occupational exposure. The ECP is also updated to reflect new or revised
employee positions with occupational exposure. (b)
This facility is located in __________ county which has reported cases
of TB in the last twelve month reporting period. Employee
Exposure Determination (Paragraph (c)(2)(i)(A)) ALL employees in the following job classifications have or may have
occupational exposure to TB (Paragraph(c)(1)(i)(A)): JOB TITLE ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Employees in the following job classifications have or may have
exposure to TB when they are performing the listed tasks and procedures
(Paragraph (c)(1)(B)):
______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Employee
Notification of TB Hazard (Paragraph (c)(2)(i)(B)) (organization's name ) uses the following procedures to assure that
all employees with job tasks that offer potential for occupational exposure
are informed of the hazard and take proper precautions against exposure to
TB. (procedures
described) ______________________________________________________________________ (*)
________ (responsible person(s)/department) ________ maintains contact with
all outside contractors who provide temporary or contract employees who may
incur occupational exposure. This allows the contractor to institute
precautions to protect his or her employees. Theses contractors are informed
of the TB hazard and the facility's procedures for protecting themselves from
exposure. (*)
Signs are posted at the entrance to: (*)
1) Rooms or areas used to isolate an individual with suspected or confirmed
infectious TB, (*)
2) Areas where procedures or services are being performed on an individual
with suspected/confirmed infectious TB, and (*)
3) clinical land research laboratories where M. tuberculosis is
present. (*)
All signs are red with white text stating "No Admittance Without a Type
N95 of More Protective Respirator" and have a picture of a stop sign. (See
attached sample). (*)
________ (organization's name) ________ ensures that warning labels are
placed on AFB isolation room exhaust ducts and areas where occupational
exposure to TB is expected. (*)
All systems carrying air that may be contain aerosolized M. Tuberculosis
are labeled at all points where ducts are accessed prior to HEPA filter, at
fans and at the discharge outlets of non-HEPA filtered direct discharge
systems. The label says: "Contaminated Air -- Respiratory Protection
Required". (*)
____ (organization's name) ____ notifies employees entering the laboratory
and the autopsy room of the occupational hazards by using signs at the
entrance to both these locations. These signs indicate the name and telephone
number of the director of the laboratory, infectious agent -- M.
tuberculosis, and the special requirements for entering the laboratory or
autopsy room. The sign displays the Biohazard symbol. Exposure
Incident Reporting (Paragraph (c)(2)(i)(C)) All employees must report exposure incidents immediately to
(responsible person(s)/department). ____ (Organization's name) is responsible
for investigating, evaluating, and documenting the circumstances surrounding
the exposure incident for instituting changes to prevent similar occurrences. The
following procedures are used to investigate/evaluate exposure incidents at
(organization's name): ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Prompt
Identification of Individuals With Suspected or Confirmed Infectious TB
(Paragraph (c)(2)(ii) and (iii)(A)) (Organization's name) considers an individual to be suspected of
having Infectious TB (unless the individual's condition has been medically
determined to result from a cause other than TB) if either the company or any
of its employees determine(s)/learn(s)that the individual:
·
has
a positive AFB smear, Based
on the criteria listed above, (Organization's name) utilizes the following
procedures for early detection of individuals with suspected/confirmed
infectious TB. ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Employers
Who Transfer (Paragraph(c)(2)(ii)) Procedures
for Transfer of Individuals With Suspected or Confirmed Infectious TB: If/when an isolation room is not available at our facility, the
individual is transferred within 5 hours of identifying the infectivity to a
facility (name of facility) where isolation rooms are available. The
following procedures for transfer of an individual with suspected/ confirmed
infectious tuberculosis are utilized: ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ While awaiting
transfer, the individual is masked or segregated to protect employees who are
without respiratory protection. (organization's name) uses the following
procedures/equipment when masking and segregating an individual with
suspected/confirmed infectious TB:
______________________________________________________________________ ______________________________________________________________________ If a situation arises
and the individual is not able to be transferred within 5 hours of
identifying the suspected or confirmed infectious TB, the following
procedures, including AFB isolation, are instituted: (list procedures used) ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Employers
Who Admit and Provide Medical Services (Paragraph (c)(2)(iii)) Procedures
to Isolate and Manage Care (Paragraph(c)(2)(iii)(B)) (*)
The following procedures are used to isolate individuals with suspected or
confirmed infectious TB. (*)
All individuals with suspected or confirmed infectious TB are placed in AFB
isolation rooms or areas. (*)
______ (organization's name) ______ uses the following procedures to minimize
the time an individual with suspected or confirmed infectious TB remains
outside of an AFB isolation room or area: ______ (detail responsibilities and
steps) ______________________________________________________________________ ______________________________________________________________________ (Paragraph(C)(2)(iii)(B)(1)) (*)
Employee exposure in AFB isolation rooms is minimized by combining tasks the
amount of time an employee spends in an AFB isolation room is minimized by
______ (list procedures used) ______________________________________________________________________
___________ Paragraph (c)(2)(iii)(B)(2)) (*)
____ (organization's name) ______ uses the following procedures, minimizing
the number of workers entering AFB isolation rooms: ______________________________________________________________________ ______________________________________________________________________ (*)
____ (organization's name) ______ utilizes the following procedures to delay
transport or relocation within the facility until the individual is
considered non-infectious: ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ (Paragraph
(c)(2)(iii)(B)(3)) (*)
Services are provided in the patient's room whenever feasible such as
portable x-ray and ______ (list other services provided in the patient's room
to minimize exposure) ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ (*)
This facility uses ________ (list the type of engineering controls in use --
properly fitted masks or valveless respirators for the for the patient to be
masked or portable containment devices) ______________________________________________________________________ on
individuals with suspected or confirmed infectious TB when it is necessary to
transport or relocate the individual. (Paragraph
(c)(2)(iii)(B)(4)) (*)
The following procedures assure that the individual is returned to the AFB
isolation room as soon as practical after completion of the procedure ______
(list of procedures) ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ (*)
Services that cannot be rendered in the patient's room are provided in and
area that meets the requirements for an AFB isolation room. (*)
Elective high-hazard procedures and surgery are delayed until the patient is
non-infectious.(Paragraph(c)(2)(iii)(B)(5)) (*)
HIGH-HAZARD PROCEDURES (Paragraph(c)(2)(iii)(C)) (*)
High-hazard procedures (where TB may be aerosolized) require precautions to
prevent/minimize occupational exposure to infectious TB. The following
high-hazard procedures are performed at this facility: ______ (list
procedures) ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ (*)
Engineering Controls Maintenance Schedules and Records (Paragraph
(c)(2)(iii)(D)) (*)
The maintenance schedule for engineering controls is as follows: (*)
Daily -- Negative pressure areas are qualitatively demonstrated by using
smoke trails. (*)
Whenever HEPA filters are changed, the system is inspected and its
performance monitored in accordance with current USPHS guidelines. HEPA
filters are changed every ______ in this facility or whenever ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ (*)
Every six months -- HEPA filters in contained air exhaust systems are
inspected, maintained and performance monitored in accordance with current
USPHS guidelines. Clinical
and/or Research Laboratories (Paragraph (c)(2)(iv)) The
________ (type of laboratory -- clinical or research) ________ operates at
biosafety level ________ as determined by ________ (name of laboratory
director) ________ for ________ (organization's name) ________. This is in
accordance with CDC/NIOSH Biosafety in Microbiological and Biomedical
Laboratories). The
following controls are in operation in the laboratory at this facility
________ (list controlled access, anterooms, sealed windows and other
controls required in the standard and determined necessary by the laboratory
director) ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ (c)(2)(v)
HOME HEALTH CARE OR HOME-BASED HOSPICE See
the following sections of this sample ECP for information regarding the ECP
requirements: (1)
(c)(2)(ii) & (iii)(A) for sample statements regarding the Prompt
identification of individuals with suspected or confirmed infectious TB. (2)
(c)(2)(iii) for sample statements re: procedures for minimizing employee
exposure. (3)
(c)(2)(iii)(C) for a sample statement regarding high hazard procedures. The
procedures in this Exposure Control Plan minimize the occupational exposure
to TB. The procedures for isolating and managing care are used until the
individual with suspected or confirmed infectious TB is determined to be
non-infectious or until the diagnosis for TB is ruled out. Evaluation Early
Detection of Tuberculosis This
questionnaire gives guidance in identifying individuals who meet OSHA's
definition of "suspected infectious tuberculosis" so that
appropriate controls can be initiated. The
questionnaire has two parts: (1) reviewing the individual's TB history and
(2) assessing current symptoms. INSTRUCTIONS:
·
Add
your comments as the evaluator at the bottom of the page. ·
Institute
the facility's exposure control measures outlined in the facility's Exposure
Control Plan, Respiratory Protection and Medical Surveillance Program and
refer the individual for further evaluation if the individual has: (1) A persistent cough lasting 3 or more
weeks and two or more symptoms of active TB. (2)
Had a positive TB test on mucous that he/she coughed up. (3)
Been told that he/she had TB and was treated, but never finished the
medication.
Evaluator
Comments: ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Exposure
Control Methods Implemented? Yes No Referred for Further Evaluation? Yes No Evaluator's Signature Date Appendix G to 1910.1035 -- Smoke-trail Testing Method for Negative
Pressure Isolation Rooms or Areas A. Test Method Description The
purpose of a negative pressure AFB isolation room or area is to prevent TB
droplet nuclei from escaping the isolation room or area and entering adjacent
or surrounding spaces (e.g., a corridor). One method to check for
negative room pressure is to use smoke-trails to demonstrate that the
pressure differential is inducing airflow from the corridor through the crack
at the bottom of the door (undercut) and into the isolation room or area. When
performing a smoke-trail test, follow these recommendations where applicable: 1.
Test only with the isolation room or area door shut. If not equipped with an
anteroom, it is assumed that there will be a loss of space pressure control
when the isolation or area door is opened and closed. It is not necessary to
demonstrate direction of airflow when the door is open. 2.
If there is an anteroom, release smoke at the inner door undercut, with both
anteroom doors shut. 3.
In addition to a pedestrian entry, some isolation rooms or areas are also
accessed through a wider wheeled-bed stretcher door. Release smoke at all
door entrances to isolation rooms or areas. 4.
So that the individual conducting the test does not advertently force the
smoke into the isolation room or area, hold the smoke bottle/tube parallel to
the door so the smoke is released perpendicular to the direction of airflow
through the door undercut. 5.
Position the smoke bottle/tube tight to the floor, centered in the middle of
the door jamb and approximately two inches out in front of the door. 6.
Release a puff of smoke and observe the resulting direction of airflow. Repeat
the test at least once or until consistent results are obtained. 7.
Minimize momentum imparted to the smoke by squeezing the bulb or bottle
slowly. This will also help minimize the volume of smoke released. 8.
Depending on the velocity of the air through the door undercut, the smoke
plume will stay disorganized or it will form a distinct streamline. In either
case, the smoke will directionally behave in one of three ways. It will: (a)
Go through the door undercut into the isolation room or area, (b)
Remain motionless, or (c)
Be blown back into the corridor. Negative
pressure requires that the smoke be drawn into the isolation room or area
through the door undercut. 9.
Release smoke from the corridor side of the door only for occupied AFB
isolation rooms or areas. If the room is unoccupied, also release smoke
inside the isolation room or area (same position as in Step No. 5) to verify
that released smoke remains contained in the isolation room or area (i.e.,
the smoke serves as a surrogate for TB droplet nuclei). 10.
To assist in observing the smoke when photography or videotaping is
performed, it is recommended that a dark surface be placed on the floor to
maximize the contrast. Be aware that most autofocusing cameras cannot focus
on smoke. B. Testing "As Used" Conditions Testing
of negative pressure AFB isolation rooms or areas requires that the test
reflect as-used conditions. As-used means that the isolation room or area
shall remain the same during testing conditions as it is when in use for
isolation. Consider the following use variables that may affect space
pressurization and the performance of the negative pressure AFB isolation
room or area: 1.
Patient toilet rooms are mechanically exhausted to control odors. The
position of the toilet room door may affect the pressure differential between
the isolation room or area and the corridor. Smoke-trail tests should be
performed both with the toilet room door open and the toilet room door
closed. This will not be necessary if the toilet room door is normally closed
and controlled to that position by a mechanical door closer. 2.
An open window will adversely affect the performance of a negative pressure
AFB isolation room or area. If the isolation room or area is equipped with an
operable window, perform smoke-trail tests with the window open and the
window closed. 3.
There may be corridor doors that isolate the respiratory ward or wing from
the rest of the facility. These corridor doors are provided in the initial
design to facilitate space pressurization schemes and/or building life safety
codes. Leaving the corridor doors open to the rest of the facility may cause
pressure changes in the corridor (e.g., proximity to an elevator
lobby) and affect the performance of the negative pressure AFB isolation room
or area. Perform isolation room or area smoke-trail testing with these
corridor doors in their "as-used" position, which is either
normally open or normally closed. 4.
Isolation rooms or areas may be equipped with auxiliary, fan-powered,
recirculating, stand alone HEPA filtration or UV units. These units must be
running when smoke-trail tests are performed. 5.
Do not restrict corridor foot traffic while performing smoke-trail tests. 6.
Negative pressure is accomplished by exhausting more air than is supplied to
the isolation room or area. Some HVAC systems employ variable air volume
(VAV) supply air and sometimes VAV exhaust air. By varying the supply air
delivered to the space to satisfy thermal requirements, these VAV systems can
adversely impact the performance of a negative pressure isolation room. If
the isolation room or area or the corridor is served by a VAV system, the
smoke test should be performed twice. Perform the smoke test with the thermostat
set at the desired temperature and again with the thermostat set at a lower
or higher temperature, depending upon the season, thus simulating the full
volumetric flowrate range of the VAV system serving the area being tested. C. Smoke Most
smoke tubes, bottles and sticks use titanium chloride (TiCl4) to
produce a visible fume. There is no OSHA PEL or ACGIH TLV for this chemical,
although it is a recognized inhalation irritant. Health care professionals
may be concerned about releasing TiCl4 around pulmonary patients. The
smoke released at the door undercut makes only one pass through the isolation
room and is exhausted directly outside. (Isolation room air is typically not
"recirculated.") The
CDC in the supplementary information to the 1994 TB Guidelines has indicated
that "The concern over the use of smoke is unfounded."(Ex. 4B)
Controlled tests by NIOSH have shown that the quantity of smoke released
during the test is so minute that it is not measurable in the air. Nonirritating
smoke tubes are available and may be utilized. [FR
Doc. 97-27020 Filed 10-16-97; 8:45 am] Footnote(1) Using the state-wide estimate of population
risk as the background estimate of risk for this study most likely results in
an underestimate of the true excess risk due to occupational exposure,
because the true background estimate of risk for the western region in North
Carolina is expected to be less than the state-wide estimate, which is
influenced by the large number of infections found in the eastern region of
that state. Footnote(2) Using the prevalence of TB infection in 1992
(i.e., Pi(1992)) to approximate the quantity inside the summation
sign (i.e., everyone infected between 1919 and 1992 and alive in 1994)
slightly overestimates the quantity inside the summation (i.e., Pi(1992)
is slightly larger than the quantity it approximates.) It includes a small
number of people who were infected with TB and were alive as of 1992 and who
were therefore included in the prevalence figure, but who died before 1994,
and, technically, are not included in the summation. This implies that, in
equation (5), a slightly larger number is being subtracted from Ai(1994)
than should be, resulting in an underestimate of the number of new infections
in 1994 and an underestimate of the occupational risk. Footnote(3) Regulatory Flexibility Act states that a
Regulatory Flexibility Analysis need not contain all of the above elements in
toto if these elements are presented elsewhere in the documentation and
analysis of the rule. The Regulatory Flexibility Analysis should, however,
summarize where these elements can be found elsewhere in the rulemaking
record. |
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