This document specifies the performance and general test methods of liquefied natural gas fuel system components, intended for use on the types of motor vehicles as defined in ISO 3833. This document is also applicable to other LNG-fueled motor vehicles as far as appropriate, until any specific norm is worked out for such a type of vehicle. It also provides general design principles and specifies requirements for instructions and marking.This document is not applicable to the following:a) fuel containers;b) stationary gas engines;c) container mounting hardware;d) electronic fuel management;e) refuelling receptacles.It is recognized that miscellaneous components not specifically covered herein can be examined to meet the criteria of this document and tested according to the appropriate functional tests.All references to pressure in this document are to be considered gauge pressures unless otherwise specified.This document is based upon a working pressure for natural gas as fuel of 1,6 MPa (16 bar)1. Other working pressures can be accommodated by adjusting the pressure by the appropriate factor (ratio). For example, a 2 MPa (20 bar) working pressure system will require pressures to be multiplied by 1,25. 1 1 bar = 0,1 MPa = 105 Pa; 1 MPa = 1 N/mm2.