P100, N100 and R100 filters in place of HEPA filters

March 18, 1996
Kenneth V. Vaughan, President
Neoterik Health Technologies, Inc.
[Recipient address omitted]
Dear Mr. Vaughan:
This is in reply to your letter, dated March 7, 1996, concerning the relationship between OSHA standards and the usage of particulate respirators certified under 42 CFR 84. Specifically, you requested clarification concerning the requirement in the OSHA asbestos standards to use a HEPA filter respirator if concentrations do not exceed 1 fiber/cc.
It is OSHA policy that when any OSHA standard requires the use of HEPA filters then the employer may satisfy the requirement by choosing to use a P100, N100, or R100 filter certified under 42 CFR Part 84, since such filters would exhibit minimum leakage. The employer would be expected to choose either the P-, N-, or R-filter based on the environmental conditions under which the respirator would be worn.
Please contact this office if we can be of further assistance.
Sincerely,
Kenneth W. Gerecke
Assistant Regional Administrator
[Corrected 10/22/2004]

[Requester letter reproduced on OSHA page; omitted here.]