Abstract: A fluid pressure regulator for delivering a gas, e.g. oxygen, from a high-pressure source, e.g. storage cylinder, to an apparatus, e.g. welding torch, at a lower adjustably controllable pressure. The regulator is characterized in that sources of combustible materials normally used for valve seating are minimized and destruction of the seat does not open the regulator to full source pressure. An improved pressure relief valve vents the regulator to ambient atmosphere in the event of either large pressure surges or elevated temperatures inside of the regulator, regardless of pressure.