Preface:

This is the second edition of ANSI/CSA NGV 5.1, Residential fueling appliances.

CSA Group acknowledges that the development of this Standard was made possible, in part, by the financial support of the Advanced Research Projects Agency-Energy (ARPA-E), U.S. Department of Energy, under Award Number DE-AR000375.

Scope:

1.1 General
This Standard details mechanical, physical, and electrical requirements for a newly manufactured appliance that dispenses natural gas for vehicles directly into the vehicle natural gas fuel storage system, referred to as a residential fueling appliance (RFA).

1.2 Application
These requirements apply to appliances:
a) for natural gas only (see Clause 1.1)
b) for outdoor or indoor installation in nonliving spaces (e.g., garage)
c) for ambient temperature not below minus 40°C (minus 40 °F)
d) for nominal voltage not exceeding 240 Volts AC
e) for fill pressure not exceeding specified vehicle service pressure
f) for maximum inlet flow rate not exceeding 10 SCFM (17 SCMH)
g) intended for connection to residential utility gas piping system in accordance with requirements of the applicable Code
h) intended to meet the installation fire safety requirements in accordance with the requirements of the applicable Code
i) single and dual fueling hose gas compressor packages

1.3 Pressure references
All references to "kpa" and "psi" throughout this Standard are to be considered gauge pressures, unless otherwise specified.

1.4 Resolution of conflicts
In the case of conflict between this Standard and Federal, National, Provincial, State, or local requirements, the authority having jurisdiction requirements take precedence.

1.5 Units of measure
This Standard contains SI (Metric) units corresponding to the inch/pound quantities, the purpose being to allow the standard to be used in SI (Metric) units. If a value for a measurement and a corresponding value in other units are stated, the first stated value is to be regarded as the requirement. The given corresponding value may be approximate. If a value for a measurement and a corresponding value in other units are both specified as a quoted marking requirement, the first stated unit, or both are to be provided.
Note: IEEE/ASTM SI 10 or ISO 80000-1 is used as a guide in making metric conversion from inch/pound quantities.

1.6 Terminology
In this Standard, "shall" is used to express a requirement, i.e., a provision that the user shall satisfy in order to comply with the standard; "should" is used to express a recommendation or that which is advised but not required; and "may" is used to express an option or that which is permissible within the limits of the standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.