3913576 is referenced by 9 patents and cites 11 patents.

Breathing apparatus which incorporates a sensing device operable to adjust the amount of breather's exhaled gas captured in a gas collector section as a direct function of flow rate and volume of the previous inhalation. The amount of exhaled gas captured is sufficiently low in carbon dioxide (CO.sub.2) content to permit rebreathing on the next inhalation, at which time the sensor again adjusts the volume of exhaled gas to be captured. In the one embodiment, a fire fighter's breathing system is described wherein the gas collector section is integral with the breathing mask worn by the fire fighter.

Breathing apparatus
Application Number
Publication Number
Application Date
November 6, 1973
Publication Date
October 21, 1975
Smith Norman E
Colston John R
Martin Frank E
Schron D
Westinghouse Electric Corporation
A62B 07/04
A62B 07/02
A62B 07/00
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