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Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

April 12, 1999

Mr. Francis J. Roth, MS, CSP
108 Solway Circle
Chalfont, PA 18914

Dear Mr. Roth:

This letter is in response to your inquiry of March 26, 1999 concerning the Occupational Safety and Health (OSHA) regulation on Respiratory Protection for M. tuberculosis, 29 CFR 1910.139. Specifically, you asked how often a health care facility must perform the fit test required by 29 CFR 1910.139(e)(5)(i) for employees who must wear a respirator for protection against Mycobacterium tuberculosis (M. tuberculosis).

Under this standard, fit testing must be performed initially (before the employee is required to wear the respirator in the workplace) and must be repeated whenever respirator design or facial changes occur that could affect the proper fit of the respirator. Examples of conditions which would require additional fit testing of an employee include (but are not limited to) the use of a different size or make of respirator, weight loss, cosmetic surgery, facial scarring, the installation of dentures or absence of dentures that are normally worn by the individual.

We do not currently require annual fit testing if the respirator is used only for protection against tuberculosis. However, this situation is likely to change when the final standard for Occupational Exposure to Tuberculosis is published. The final standard, as proposed in the October 17, 1997 Federal Register, would require fit testing to be performed for the above reasons and at least annually unless certain medical surveillance requirements are met.

Please bear in mind that the standard for all other substances, including any other airborne pathogens, is the revised respiratory protection standard, 29 CFR 1910.134. This standard requires that respirators be fit tested prior to initial use, whenever a different respirator face piece is used (size, style, model, or make), and at least annually thereafter. It is strongly recommended that employers follow this same frequency for protection against tuberculosis.

I hope this clarifies the requirements for fit testing respirators that are used for protection against tuberculosis. If you have any further questions, please feel free to contact OSHA's Office of Health Compliance Assistance at (202) 693-2190.


Richard E. Fairfax
Directorate of Compliance Programs