Standard Interpretations - Table of Contents
• Standard Number: 1910.156(f); 1910.134(c)

June 15, 1983

MEMORANDUM FOR: REGIONAL ADMINISTRATORS
ATTN: ARA's for Technical Support
THRU: JOHN B. MILES
Director, Field Coordination
FROM: EDWARD J. BAIER
Director, Technical Support
SUBJECT: Acceptance of Closed-Circuit Self-Contained Breathing Apparatus

We have received numerous inquiries concerning OSHA's acceptance of two positive-pressure closed-circuit self-contained breathing apparatus (PPCCSCBA), the BioPak 60P and 30P (TC-13F-85 and 84). The major concerns have been whether these devices are permissible for use in atmospheres which are immediately dangerous to life or health (IDLH) or for use in the fire service.

Your may recall that early in 1979, we accepted the BioPaks as a positive-pressure SCBA based on the performance tests conducted by NIOSH in spite of the fact that there are no certification criteria for the PPCCSCBA. Since then the Los Alamos National Laboratory (LANL) and the Lawrence Livermore National Laboratory (LLNL) have conducted comprehensive quantitative fit testing and fire testing of the BioPaks. The LANL results indicate that the BioPaks are positive-pressure SCBAs and when well fitted an individual can obtain a fit factor of 20,000 or higher which is equivalent to the