US Patent 7866340 Universal pressure reducer for self-contained breathing apparatus

A universal pressure reducer is provided for a self-contained breathing apparatus. The universal pressure reducer includes an inlet, a reducer module in fluid communication with the inlet, a pneumatic alarm mechanism, and a pneumatic transfer valve assembly that controls the actuation of the alarm mechanism by controlling the flow of pressurized air thereto. The transfer valve assembly is arranged to actuate the alarm mechanism when the pressure of air entering the reducer through the inlet drops to a predetermined trigger level. The predetermined trigger level is automatically selected based on a rated capacity of a pressure vessel to which the inlet is connected through a cylinder valve.