The safety/pressure relief valve is a standard diaphragm safety/pressure relief valve, which is mainly used in heating, air conditioning, thermal storage hot water systems, irrigation systems, control of cold and heat sources and system pressure. When the system pressure exceeds the set value of the safety valve, the safety valve automatically opens to release the system pressure to the atmosphere, and automatically closes when the pressure is lower than the safety value, so that the system with the safety valve can operate safely.