CSA 9.4:21

1 Scope 1.1 This Standard applies to newly produced manually operated metallic gas shut-off valves, hereinafter referred to as valves, constructed entirely of new, unused parts and materials that a) are for indoor/outdoor installation; b) are for use in the gas piping between the outlet of the gas distributor's meter and the inlet connection of the pressure regulator installed upstream of the manual valve in the gas piping to each appliance; c) are capable of operation at ambient temperatures between 32 to 125 °F (0 to 52 °C) if intended for indoor use only, or temperatures between –40 to 180 °F (–40 to 82 °C) if intended for indoor/ outdoor use; d) are to be rated for either 2 psig (14 kPa) or 5 psig (35 kPa); and e) include sizes 1/4 through 4 in NPS and tubing sizes 1/4 in through 1 in O.D. 1.2 A valve covered under this Standard is for use with natural gas, manufactured gas, or propane gas. 1.3 This Standard sets forth the minimum capabilities, characteristics, and properties that a valve must possess, at the time of manufacture, in order to be considered suitable for use in an indoor/outdoor gas piping system. Details of design and manufacture, other than those stated in this Standard, including such design and production tests that will produce a valve that will have the required capabilities to meet the Standard, remain the responsibility of the manufacturer. 1.4 All references to pressure throughout this Standard are to be considered gauge pressures, unless otherwise specified. 1.5 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 (non-mandatory) to define their application.