Preface 

This is the first edition of CSA/ANSI LNG 4.1, Liquefied natural gas (LNG) dispensing systems for natural gas vehicles (NGV). This publication represents a standard for safe operation, substantial and durable construction, and performance testing of components for natural gas vehicle LNG dispensing systems, within limitations given below and in the scope of this Standard. This Standard is based on proven engineering principles, research, and the combined expertise of gas utilities, manufacturers, users, and others having specialized experience. Nothing in this Standard is to be considered in any way as indicating a measure of quality beyond compliance with the provisions it contains. It is designed to allow compliance of products which may exceed that specified in the provisions herein. In its preparation, full recognition has been given to possibilities of improvement through ingenuity of design. This Standard is subject to revision as further experience and investigation may show it is necessary and desirable. CSA Group, and their respective Laboratories, does not assume or undertake to discharge any responsibility of the manufacturer or any other party. CSA Group will not incur any obligation or liability for damages, including consequential damages, arising out of or in connection with the use, interpretation of, or reliance upon this Standard. Users of this Standard are advised that the devices/products/activities within its scope may be subject to regulation at the Federal, state, provincial, or local levels. Users are strongly urged to investigate this possibility through appropriate channels. In the event of a conflict with this Standard, the Federal, state, provincial, or local regulations should be followed. This Standard was prepared by the Subcommittee on Liquefied Natural Gas Dispensing Systems for Natural Gas Vehicles, LNG 4.1, under the jurisdiction of the Technical Committee on Natural Gas Transportation and the Strategic Steering Committee on Transportation. It has been formally approved by the Technical Committee. This Standard has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group. This Standard was approved by the American National Standards Institute (ANSI) as an American National Standard on June 19, 2018. 

Scope 

1.1 

1.1.1 This Standard applies to: a) the mechanical and electrical features of newly manufactured stationary and mobile systems that dispense "cold" or "warm" liquefied natural gas for vehicles where such a system is intended primarily to dispense the fuel directly into the fuel storage container of the vehicle; b) LNG dispensers contained in a single housing; and c) LNG dispensers contained in multiple housings for metering and registering devices, remote electronics, overfill protection, hoses, and fuelling nozzles. 

1.1.2 Each dispenser may have the capability of independently fuelling more than one vehicle simultaneously. 

1.1.3 Dispensers covered by this Standard are intended for use with liquefied natural gas, a fluid in the liquid state at cryogenic temperatures that is composed predominantly of methane and that can contain minor quantities of ethane, propane, nitrogen, or other components normally found in natural gas. 

1.1.4 This Standard does not apply to: a) rail locomotive dispensing systems; b) marine vessel bunkering systems; c) compressed natural gas dispensers; d) fuel management systems or point of sales systems; and e) remote sequencing equipment and other remote equipment not supplied as part of the dispenser. 

1.1.5 Installation of an LNG dispenser is intended to be in accordance with NFPA 52, or CSA B108, Part 2, as applicable, and the requirements of the authority having jurisdiction (AHJ). 

1.1.6 In this Standard, "shall" is used to express a requirement, i.e., a provision that the user is obliged to 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 (nonmandatory) to define their application. 

1.2 All dimensions used in this Standard are in metric units [International System of Units (SI)], unless otherwise specified. If a value for a measurement, as given in this Standard, is followed by an equivalent value in other units, the first stated is to be regarded as the specification. 

1.3 All references to pressure throughout this document are to be considered gauge pressures unless otherwise specified. 1.4 Annex A contains Clauses that are unique to Canada.