Alcance
ISO 15500-12:2015 specifies tests and requirements for the pressure relief valve (PRV), a compressed natural gas fuel system component intended for use on the types of motor vehicles defined in ISO 3833.ISO 15500-12:2015 is applicable to vehicles using natural gas in accordance with ISO 15403-1 (mono-fuel, bi-fuel, or dual-fuel applications). It is not applicable to the following:a) liquefied natural gas (LNG) fuel system components located upstream of, and including, the vaporizer;b) fuel containers;c) stationary gas engines;d) container mounting hardware;e) electronic fuel management;f) refuelling receptacles.NOTE 1 It is recognized that miscellaneous components not specifically covered herein can be examined to meet the criteria of this part of ISO 15500 and tested according to the appropriate functional tests.NOTE 2 All references to pressure in this part of ISO 15500 are to be considered gauge pressures unless otherwise specified.NOTE 3 This part of ISO 15500 is based upon a service pressure for natural gas as a fuel of 20 MPa [200 bar[1]] settled at 15 �C. Other service pressures can be accommodated by adjusting the pressure by the appropriate factor (ratio). For example, a 25 MPa (250 bar) service pressure system will require pressures to be multiplied by 1,25.[1] 1 bar = 0,1 MPa = 105 Pa; 1 MPa = 1 N/mm2.