What the CDC says about proposed TB standard

Excerpts from the U.S. Centers for Disease Control and Prevention's testimony1 on the U.S. Occupational Safety and Health Administration's proposed tuberculosis standard2 are presented here in a question-and-answer format (OSHA questioning and the CDC answering), as follows:

Exposure Control Plan

Q: Would the collection and analysis of aggregate data regarding employee tuberculin skin test (TST) conversions provide benefits beyond those provided by investigating individual exposure incidents or conversions?

A: Aggregate data regarding employee TST conversions and TB exposures are necessary to determine if existing controls and recommendations are sufficient and to identify problem areas where additional interventions are needed. Facilitywide and area- or unit-specific aggregate data should be evaluated at least annually as part of the required exposure control plan review.


Q: Is it appropriate to require employees who are transporting an unmasked patient with suspected or confirmed infectious TB within a facility to wear a respirator? What other precautions should be taken when transporting a patient who is not masked?

A: According to the 1994 CDC guidelines, patients with confirmed or suspected TB should wear a surgical mask when being transported.3 Patients who are unable to wear a mask include those who are intubated and/or receiving ventilatory support, neither of which is common among TB patients. All employees transporting unmasked patients with confirmed or suspected active TB should wear respirators, and the hallways and elevators should be cleared prior to transporting the patient.

Q: Should OSHA require use of a respirator that is more protective than an N95 type of respirator in certain circumstances? If so, what are the circumstances and what type of respiratory protection should be required?

A: OSHA should include provisions that permit respirators more protective than N95 half-mask respirators, but we do not recommend that the TB standard specify conditions when these must be used. The need for more protective respirators should be determined by individual institutions as outlined in the 1994 CDC guidelines.

Q: OSHA is permitting the reuse of disposable respirators provided they do not exhibit excessive resistance, physical damage, or any other condition that renders them unsuitable for use. Will the respirators continue to protect employees throughout the reuse period?

A: Disposable respirators may be reused and still provide protection under certain conditions. We recommend specifying that proper use of all respirators requires them to be used within the conditions and limitations specified by the manufacturer.

Medical Surveillance

Q: Employees providing home health care to individuals with suspected or confirmed infectious TB may have the same potential for exposure to aerosolized M. tuberculosis as employees who enter an isolation room. Should those home health care employees be skin-tested every six months?

A: Annual testing should be sufficient. Most patients discharged to home are no longer infectious.

Q: Should OSHA require specific training for individuals who are administering, reading, and interpreting TSTs? If so, what type of training should be required?

A: OSHA should require specific training in placement and reading of skin tests to assure accurate interpretation. We recommend that this training be consistent with current requirements or recommendations of state and local TB control programs since there is no national standard for training.


1. Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. Testimony of the National Institute for Occupational Safety and Health on the Occupational Safety and Health Administration proposed rule on occupational exposure to tuberculosis. 29 CFR Part 1910. Docket No. H-371. Washington, DC; April 1998.

2. Department of Labor, Occupational Safety and Health Administration. Occupational exposure to tuberculosis; proposed rule. 62 Fed Reg 54,159-54,307 (Oct. 17, 1997).

3. Centers for Disease Control and Prevention. Guidelines for preventing the transmission of Mycobacterium tuberculosis in health care facilities, 1994. MMWR 1994; 43 (No. RR-13):1-132.