Abstract: A valve assembly for use in breathing apparatus which is made in two sub-assemblies to facilitate repair at low cost. One assembly is adapted to be detachably mounted to a face mask and carries modules for communication accessories. A second subassembly is threadedly attached to the first sub-assembly and carries the valving members necessary to admit air or breathable gases to the face mask and to allow the escape of exhaled gases. The second sub-assembly valve portion is made in two sections which can be disassembled for repair with readily replacable valving elements for easy maintenance.

Abstract: A face mask for pressure breathing. The mask has a body with a sealing boundary shaped to fit over the bridge of a wearer's nose, downward past the sides of his nose and mouth and across his mental protuberance. The sealing boundary includes a reflective primary seal and a secondary seal. The reflective seal lays flexibly against the wearer's face. The secondary seal is relatively rigid relative to the reflective seal so as to indent into the face when pressed against it in order to respond to stringent conditions of g forces and differential pressures.

Abstract: A breathing valve for the selective entry of a gas to be inhaled and for the exit of exhaled gas, which utilizes a rolling diaphragm and flapper valves for its workings which are quiet and are constructed so as to be unlikely to freeze up or become sticky.