Standard Interpretations - Table of Contents
• Standard Number: 1910.1001

September 25, 1986

Tim Sekulic, P.E., C.I.H.
T.S. Sekulic Engineering
3 Mount Vernon Avenue
Summit, New Jersey 07901

Dear Mr. Sekulic:

This is in response to your letter of August 18, concerning the respirator fit testing requirements in the revised asbestos standard, 29 CFR 1910.1001.

Qualitative fit testing of full-face-piece respirator that are used only in the lower airborne asbestos concentrations that half-face-piece respirators may be worn is considered to accord with the asbestos standard.

Thank you for bringing your concern to our attention. If we may assist you again in the future, please do not hesitate to contact us.


John B. Miles, Jr., Director
Directorate of Field Operations

Mr. John Miles
Director of Field Operations
Room N 3603
200 Constitution Avenue, N.W.
Washington, D.C. 20210

RE: Clarification of Respiratory Protection Provisions of the Revised Asbestos Standard

Dear Dr. Miles:

My understanding of the respirator fit testing requirements of the revised asbestos regulations is that a worker may not use a full-face respirator, even for exposure levels less than ten times the PEL, unless the he has passed a quantitative fit test. However, only qualitative fit testing is required in order to use a half-face respirator for such exposures.

The justification for this appears to be that adequate data verifying the capability of qualitative fit testing for a protection factor of ten were available for half-face but not for full-face respirators. Apparently OSHA did not deem it desirable to extrapolate the capability of qualitative fit testing for a protection factor of ten to full-face respirators, even though they have been shown by countless quantitative measurements to offer protection factors at least five-to-ten times greater than half-face respirators.

In addition to increased respiratory protection, full-face respirators pro