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.

October 1, 1999

Mr. John Hale
Respirator Support Services
2028 Virts Lane
Jefferson, MD 21755-8801

Dear Mr. Hale:

This is in response to your letter dated November 17, 1998, addressed to the Occupational Safety and Health Administration (OSHA). We apologize for the long delay in responding to your letter. In your letter you have commented that you believe there are contradictions between the OSHA's Respiratory Protection standard, 29 CFR 1910.134, and the OSHA Instruction, CPL 2-0.120 (Instruction). You have requested an explanation as to why the inspection guidelines provide "less protective practices" than the standard.

OSHA's Office of Health Compliance Assistance (OHCA) is tasked with the responsibility to ensure that employer's health standards are consistently enforced by the field inspectors. This office sets enforcement policies, provides advice to the field and to the public, and develops interpretations to the existing standards.

Your letter first addresses an inquiry regarding paragraph (d)(1)(ii) requiring the employer to select a NIOSH-approved respirator. The portion of the Instruction that you have cited provides an interpretation of section (c)(2), that allows the use of non-approved respirators when used voluntarily. The reason OSHA does not require employers to select NIOSH approved respirators for voluntary use is because voluntary use is only permitted in an environment that presents no health hazard. However, as a matter of promoting safe work practices, OSHA continues to encourage voluntary users to select NIOSH-approved equipment.

Your second concern relates to paragraph (f)(6), which states that "Qualitative Fit-Testing (QLFT) may only be used to fit test negative pressure air-purifying respirators that must achieve a fit factor of 100 or less." OSHA believes that existing evidence validates the use of qualitative fit-testing for full facepieces on negative pressure respirators as well as on SCBA's.

Lastly, you have addressed the requirement that the employer shall provide each respirator user with a respirator that is clean, sanitary and in good working order. Several inquiries were received by OSHA concerning the infeasibility of compliance with this provision for respirators used to fit test employees. Most employers do not maintain a large inventory of respirators that would allow employers to clean and disinfect the respirators between each fit testing. OSHA made the decision to address this problem by providing an interpretation of the standard that would allow employers to use towelettes between employees during fit-testing. At the end of each day, however, the respirators must be cleaned using the procedure in Appendix B-2.

We hope this provides an answer to your questions. If we can be of further assistance, please feel free to contact OSHA's OHCA, at (202) 693-2190.


Richard E. Fairfax
Directorate of Compliance Programs