The OSHA regulations on occupational exposure to tuberculosis are less well
known than the bloodborne pathogen rules but they affect a much broader set
of businesses. [Proposed Rules Department of Labor Occupational Safety and
Health Administration. 29 C.F.R. part 1910, Occupational Exposure to
Tuberculosis, Friday, October 17, 1997, 62 Fed. Reg. 54160–01 (1997).] The
following is a list of the groups, industries, and work settings that are covered
by the standard. Basically, this includes all types of medical care, social work,
and law enforcement agencies and personnel:
immigration detainment facilities
law enforcement facilities
substance abuse treatment centers
medical examiners’ offices
home medical care providers
emergency medical services
research and clinical laboratories handling TB
Contract work on ventilation systems or areas of buildings that may
contain aerosolized M. tuberculosis
physicians performing certain high-hazard procedures
social service workers providing services to individuals identified as
having suspected or confirmed infectious TB
personnel service agencies when providing workers to covered facilities
attorneys visiting known or suspected infectious TB patients
The CDC guidelines on TB control recommend that a facility does risk
assessment to determine the level of TB exposure risk for the facility as a
whole and for specific work areas and occupational groups. The CDC defines
five levels of risk based on the number of clients with active TB, the rate and
pattern of PPD skin test conversions, and whether there is evidence of person-
to-person transmission of TB. OSHA has chosen a simpler approach. Employers
are required to determine which employees have occupational exposure to TB.
OSHA then specifies that measures must be taken to protect these exposed
Institutions that have no internal TB exposure and that are in communities with
little or no active TB are exempt from some of the OSHA requirements.
However, some actions are required of all covered institutions:
There must be a written exposure control plan.
Baseline PPD skin testing and medical history must be obtained on all
employees who are identified as having occupational exposure.
Medical management and follow-up must be provided after exposure
Infectious employees must be removed from the workplace until
There must be acceptable employee training and recordkeeping.
The OSHA regulations require PPD retesting every three to twelve months
depending on the level of risk and exposure history of a given employee.
Employees with a low risk of exposure may be retested yearly. Those with
higher risk must be retested every six months. The latter include those who (1)
enter AFB isolation rooms, (2) perform high- hazard procedures, (3) transport
TB patients in an enclosed vehicle, or (4) work in intake areas in an institution
with a high number of TB patients (6 in 12 months). If there has been a direct
exposure, the employee must be retested immediately and again in three
The OSHA regulations do allow for the limitations of the PPD skin test as a
screening test. Anyone who has not had a TB skin test in the last 12 months,
must have a two- step baseline test. This involves doing the test and then
repeating it in two weeks if it is negative or equivocal. This allows them to
distinguish true conversions from the booster effect. A true conversion occurs
when the patient becomes infected with TB between two tests. The booster
effect occurs when a patient has been infected in the past but does not have
high levels of antibody. The first test boosts the antibody levels so that the
repeat in two weeks will give a true reading. Contrary to popular myth, you
cannot develop a positive PPD skin test by having too many tests.
If the employee already has a documented positive PPD skin test, then it does
not have to be repeated. The employer may rely on careful history and chest X
ray when indicated to follow these employees. Routine chest X rays are not
required or recommended. In addition to regular screening of individual
employees, regulated establishments must watch for clusters of disease or skin
test conversion. These may indicate areas where active TB has gone unnoticed
or where administrative or engineering controls have broken down.
When an employee has become infected with TB, whether they have active
disease or silent infection detected on skin testing, the employer must provide
medical care and follow-up. Some states recognize such infection as a
compensable injury under workers’ compensation. Other do not. However,
under OSHA regulation, proper care and treatment must be provided.
An employee who is found to have infectious TB must be put on medical
exclusion from work until they are no longer infectious and do not pose a risk
to others. This means that a medical care professional cannot practice until
they are noncontagious. The nurse who is on medical exclusion from the
hospital may not do immunization clinics or home health visits.
An important consideration about TB control in the work environment is that it
must fit with the control of this disease in the larger community. The OSHA
regulations and recordkeeping do not negate the state public health laws. TB is
a reportable disease in every state and territory of the United States. There is
a large federal TB control program administered at the local health department
level. In addition, charity hospitals, homeless shelters, and jails have a large
number of clients in common. Patients receive better care and workers have a
safer work environment when there is coordination of TB control efforts by local
public health officials.