Abstract: An oxygen switching apparatus and method switches a flow of oxygen under pressure as between a first oxygen carrying tube and a second oxygen carrying tube. In this manner, the flow of oxygen under pressure is restricted to one nostril at a time, and the switching can prevent one nostril from becoming unduly chafed or harmed by a continuous flow of oxygen thereto. The switch can be located within the housing containing the source of pressurized oxygen, or can be external thereto.

Abstract: A retention device and method for retaining an object, including preferably a gas mask, in position proximate a user's mouth. The retention device includes straps coupled to both sides of the object and having at ends thereof ear pieces. The ear pieces fit over the ears, and are configured to receive the strap at a point proximate the tragus portion of the ear, causing pulling forces to be on the posterior center portion of the ear rather than on the top of the ear. The ear pieces have a downwardly exterior anterior leg and a downwardly extending posterior leg. In one embodiment, the ear pieces are substantially U-shaped. In another embodiment, the ear pieces are substantially ring-shaped.

Abstract: A debris cap apparatus and method, which provides a secure and debris resistant seating of a debris cap within a valve box. The debris cap has two outwardly projecting annuli—a debris seal located near the top of the cap and a retention gasket located distal from the top of the cap. The debris seal blocks debris from entering the valve box when the debris cap is in position. The retention gasket is designed to be pushed down past an inwardly projecting flange within the valve box, to deform as it passes the flange, and then to resume its original shape when past the flange so as to preclude accidental dislodging of the debris cap from the valve box. Where the debris cap is to be used within a pre-existing valve box, an adapter may be provided. It is further preferred to provide a removal tool so as to permit ready removal of the debris cap from the valve box or valve box adapter.

Abstract: Lid 12 has affixed thereto an annular resilient flap 26 which cooperates with a flange 21 on a lid support 13 to resist dislodgement of the lid. The flap 26 i worked into position beneath the flange 21 by rotation of the lid about its axis. A container portion 34 of the lid may contain a granular material to add weight to the lid.

Abstract: A cap body has a movable retaining tongue which is engageable with a portion of an access structure to retain the cap on the structure. A tongue is manipulated through a bolt, the head of which is accessible at the top surface of the cap body. A cover for the bolt head has a locking post which extends through the cap body and engages and locks the tongue against movement.

Abstract: The debris cap includes a handle activated retainer mechanism for retaining the cap in a pipe in which it is installed. The retainer mechanism includes an over-center connecting rod system for keeping the retaining mechanism in its retaining position. A barrel lock is employed to prevent unauthorized removal of the cap. A resilient flange on the body of the cap frictionally engages the wall of the pipe to support the cap as the retainer mechanism is manipulated.