The purpose of this standard is to define the construction and operation characteristics, the testing technique and the marking of pressure regulators with a maximum inlet operating pressure (MOPe) greater than 0.4 bar and less than or equal to 5 bar and a maximum outlet operating pressure (MOPs) of less than or equal to 0.4 bar with built-in safety valve for maximum pressure tripping, with built-in safety valve for minimum pressure tripping and with a nominal flow rate up to 250 m3 (n)/h.