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A Guide to Atmosphere-Supplying Respirators

September 2019
DHHS (NIOSH) Publication Number 2019-174
A Guide to Atmosphere-Supplying Respirators, cover page publication 2019-174

Atmosphere-supplying respirators provide clean breathing air from a source independent of the work area. These respirators will protect wearers from many types of airborne contaminants (particles, gases, and vapors) and, in certain cases, oxygen-deficient atmospheres. There are three types of atmosphere-supplying respirators: supplied-air respirators (SARs), self-contained breathing apparatus (SCBAs), and combination SARs/SCBAs. Respirators need to be approved by the National Institute for Occupational Safety and Health (NIOSH) Respirator Approval Program and used in the context of a complete respiratory protection program per the Occupational Safety and Health Administration (OSHA) regulation 29 CFR 1910.134, which includes annual fit testing for all respirators with a tight-fitting facepiece.

A Guide to Atmosphere-Supplying Respirators [PDF – 638 KB]

Suggested Citation

NIOSH [2019]. A Guide to Atmosphere-Supplying Respirators. By Cichowicz, J., Cofey, C., and Fries, M. Pittsburgh, PA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. DHHS (NIOSH) Publication No. 2019-174,