42 C.F.R. § 84.120 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) Inhalation valves shall be designed and constructed to prevent excessive exhaled air from adversely affecting cartridges, canisters, and filters. (c) Exhalation valves shall be protected against external influence, and designed and constructed to prevent inward leakage of contaminated air.
Title 42: Public Health
PART 84—APPROVAL OF RESPIRATORY PROTECTIVE DEVICES
Subpart I—Gas Masks
§ 84.120 Inhalation and exhalation valves; minimum requirements.
