42 C.F.R. § 84.77 Inhalation and exhalation valves; minimum requirements.
Title 42 - Public Health
(a) Inhalation and exhalation valves shall be provided where necessary and protected against damage and distortion. (b) Exhalation valves shall be— (1) Protected against external influence; and (2) Designed and constructed to prevent inward leakage of contaminated air.
Title 42: Public Health
PART 84—APPROVAL OF RESPIRATORY PROTECTIVE DEVICES
Subpart H—Self-Contained Breathing Apparatus
§ 84.77 Inhalation and exhalation valves; minimum requirements.
