Personal emergency breathing system for supplied air respirators

摘要

The personal emergency breathing system includes a canister with a filtration unit for supplying filtered ambient air to a gas mask. The mask includes a fitting from which a regulator and hose coupled to an air tank may be removed after exhaustion of the supply of air and to which the canister is coupled to supply filtered ambient air to the user. Upon removal of the canister from the mask, the canister affords an indication of prior use of the canister and is simultaneously disabled from resecurement to the gas mask.