ANSI NGV 3.1-2012/CSA 12.3-2012
Fuel system components for compressed natural gas powered vehicles
The natural gas vehicle industry relies on standards to determine the safe operation and performance of aftermarket components for (installation on) motor vehicles operating on compressed natural gas. To stay aligned with technological advances, this revised standard is fully harmonized with ISO 15500 – International Standard for Fuel System Components for Natural Gas Vehicles.
ANSI NGV 3.1/CSA 12.3-2012 contains requirements for newly produced compressed natural gas fuel system components intended for use on natural gas powered vehicles. This standard is based on engineering principles, research and the combined expertise of gas utilities, manufacturers, users and others having specialized experience.
This publication represents a standard for safe operation, substantial and durable construction, and performance testing of natural gas vehicle fuel systems, within limitations given below and in the scope of this standard.
This Standard establishes requirements for newly produced compressed natural gas fuel system components, intended for use on natural gas powered vehicles, as listed in Table 1, Fuel System Components, below.
Fuel System Components
Manual Container Valve
Gas Flow Adjuster
Pressure Relief Valve
Pressure Relief Device
Excess Flow Valve
Gas Tight Housing and Ventilation Hoses
Rigid Fuel Line
Flexible Fuel Line
Relief Line Closures
This Standard applies to devices which have a service pressure of either 16 500 kPa (2400 psi), 20 700 kPa (3000 psi), or 24 800 kPa (3600 psi), hereinafter referred to in this standard as the following
P24 - 16 500 kPa (2400 psi)
P30 - 20 700 kPa (3000 psi)
P36 - 24 800 kPa (3600 psi)
The construction of the noted components whether specifically covered by the various provisions of this standard or not, shall be in accordance with reasonable concepts of safety, substantiality and durability.
All specifications as to construction set forth herein shall be satisfied by the construction actually prescribed or such other construction as will provide at least equivalent performance.
This Standard emphasizes the pressure containment, performance and safety characteristics of components listed in Table 1, Fuel System Components.
It is recognized that other components not specifically covered herein can be examined to meet the criteria of NGV 3.1 and tested according to the appropriate functional needs.
This Standard does not apply to the following:
a. natural gas fuel system components incorporated during the manufacture of motor vehicles originally manufactured in compliance with the Federal Motor Vehicle Safety Standards (FMVSS) for Compressed Natural Gas Fueled Vehicles and the Canadian Motor Vehicle Safety Standard (CMVSS);
b. fuel containers;
c. stationary gas engines;
d. container mounting hardware;
e. electronic fuel management;
f. fueling receptacles;
g. three way valves.
In the case of conflict between this standard and Federal, Provincial, State or local requirements, the government requirements shall take precedence.