1 Scope
This Standard specifies tests and requirements for the differential pressure fuel content gauge, a liquefied natural gas fuel system component intended for use on the types of motor vehicles defined in CSA B109.2 in Canada and NFPA 52 in the U.S.
This Standard also provides general design principles and specifies requirements for instructions and marking.
This Standard is not applicable to the following:
a)
fuel containers;
b)
stationary gas engines;
c)
container mounting hardware;
d)
electronic fuel management; and
e)
fuelling receptacles.
It is recognized that miscellaneous components, not specifically covered herein can be examined to meet the criteria of this Standard and tested according to the appropriate functional tests.
All references to pressure in this Standard are to be considered gauge pressures unless otherwise specified.
This Standard is based upon a working pressure for natural gas as fuel of 1.6 MPa (232 psi). Other working pressures can be accommodated by adjusting the pressure by the appropriate factor (ratio). For example, a 2 MPa (290 psi) working pressure system will require pressures to be multiplied by 1.25.
Note: For North American application, all references to working pressure are considered to be equivalent to maximum allowable working pressure (MAWP).