665 HAZWOPER for General Site Workers VI

Supplied-Air Respirators (SARs)

• The air source for supplied-air respirators may be compressed air cylinders or a compressor which purifies and delivers ambient air to the facepiece.
• SARs suitable for use with compressed air are classified as "Type C" supplied-air respirators as defined in 42 CFR Part 84.
• All SAR couplings must be incompatible with the outlets of other gas systems used on site to prevent a worker from connecting to an inappropriate compressed gas source (OSHA 29 CFR 1910.134(d)).
• Advantages: SARs enable longer work periods than do SCBAs and are less bulky.
• Disadvantages: The air line impairs worker mobility and requires workers to retrace their steps when leaving the area.
• Also, the air line is vulnerable to puncture from rough or sharp surfaces, chemical permeation, damage from contact with heavy equipment, and obstruction from failing drums, etc. To the extent possible, all such hazards should be removed before use. When in use, air lines should be kept as short as possible (300 feet [91 meters] is the longest approved hose length for SARs), and other workers and vehicles should be kept away from the air line.

The use of air compressors as the air source for an SAR at a hazardous waste site is severely limited by the same concern requiring workers to wear respirators: in other words, the questionable quality of the ambient air. Onsite compressor use is limited by OSHA standards (29 CFR Part 1910.134[d]).

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