Abstract: A self contained breathing apparatus comprises a compressed air cylinder, facemask and hose which when not in use are stored and carried within a case formed from an assembly of flexible sheet material. The elements of the case are constructed such that when it is opened and reversed it is adapted to form a garment to be worn over the torso and support the air cylinder for use.

Abstract: In a demand valve for breathing apparatus gas flow is controlled by a main valve disc in accordance with the pressure in a control chamber. Gas vents from the control chamber through a bleed orifice at a rate dependent upon the deflection of a diaphragm sensitive to respiration and which controls the spacing of a spring arm from the bleed orifice. The arm has a set spacing from the orifice such as to provide "positive pressure" operation of the valve when the valve is connected into the inlet of an associated breathing mask. A lever on the valve contacts the mask inlet and acts through a pin to bias the arm to its "positive pressure" setting through a second spring arm. When the valve is disconnected the lever drops to allow the two arms to relax so that the first arm moves closer to the control chamber bleed orifice and thereby shuts off gas flow past the main valve disc.