CSA 6.18:25

Preface This is the fourth edition of CSA 6.18, Service regulators for natural gas . It supersedes the previous editions published by CSA in 2002 and by the Canadian Gas Association in 1995 and 1991 as CGA 6.18, Internal Relieved Service Regulators for Natural Gas. The following are the major changes to this edition: a) updated scope delivery pressure (2 psi or less) and additional temperature ratings; b) addition of Clauses 4.5, 5.5, and 9.4, and Tables 3to 9; c) updated Tables 1and 2; d) addition of integral slam-shut device coverage (see Clause 11.3); e) additional instructions to Clause 13; f) addition of Clause 14.2for slam-shut device markings; g) updated Clause 15.1.4; h) addition of Clauses 15.9.2.1and 15.9.2.4for OPCO set point requirements; i) addition of integral monitor device testing (see Clause 15.16); j) moved variable temperature performance test (see Clause 16); k) addition of manufacturing and performance testing (see Clause 19); and l) addition of internal monitor test (see Annex E). This Standard is considered suitable for use for conformity assessment within the stated scope of the Standard. This Standard was prepared by the Subcommittee on Automatic Gas Controls, under the jurisdiction of the Technical Committee on Gas Appliances and Related Accessories and the Strategic Steering Committee on Fuels and Appliances, and 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. Scope 1.1 Inclusions This Standard applies to the construction, materials, performance, and testing of NPS 1-1/4 in (32 mm) and smaller self-acting service-type regulators with overpressure protection devices utilized to control the pressure of gas delivered to a customer’s piping at a delivery pressure of 2 psi (14 kPa) or less. 1.2 Temperature ratings This Standard includes regulators capable of operation over an ambient temperature range of −40 to 150 °F (−40 to 65.6 °C) up to the pressure recommended by the manufacturer but not exceeding 125 psi (861.8 kPa). 1.3 Terminology 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. 1.4 Units of measurement The values given in U.S. customary units are the units of record for the purposes of this Standard. The values given in parentheses are for information and comparison only, or for markings where both units of measurement are required.