Patent ID: 8327848

Claim:
A pressure reducing valve, comprising: a valve body having a number of pressurized gas exhaust ports and a number of exhalation gas exhaust ports; and an inner sleeve having a number of inner ports, wherein the inner sleeve is movable within the valve body between a closed position in which the inner ports are closed and the pressurized gas exhaust ports and the exhalation gas exhaust ports are open and an open position in which the inner ports are open and the pressurized gas exhaust ports and the exhalation gas exhaust ports are closed, wherein the pressurized gas exhaust ports are structured to operatively communicate a flow of positive pressure gas provided to the pressure reducing valve through the valve body to atmosphere when the inner sleeve is in the closed position and wherein the exhalation gas exhaust ports are structured to operatively communicate a flow of exhalation gas provided to the pressure reducing valve through the valve body to atmosphere when the inner sleeve is in the closed position in a manner wherein no more than a negligible amount of mixing of the flow of positive pressure gas and the flow of exhalation gas will occur.