Preface This is the fourth edition of CSA B125.3, Plumbing fittings. It supersedes the previous editions, published in 2012, 2011, and 2005. Together with ASME A112.18.1/CSA B125.1, Plumbing supply fittings, ASME A112.18.2/CSA B125.2, Plumbing waste fittings, and ASME A112.18.6/CSA B125.6, Flexible water connectors, this Standard forms a series to cover plumbing fittings. Scope 1.1 This Standard covers plumbing fittings, including the following: a) automatic compensating valves other than those for individual wall-mounted showering systems; b) solenoid valves; c) temperature-actuated in-line mixing valves; d) thermal expansion relief valves; and e) trap primers. 1.2 This Standard does not cover the following plumbing supply fittings and accessories, which are covered by ASME A112.18.1/CSA B125.1: a) automatic compensating valves for individual wall-mounted showering systems; b) bath and shower supply fittings; c) bidet supply fittings; d) clothes washer supply fittings; e) drinking fountain supply fittings; f) humidifier supply stops; g) kitchen, sink, and lavatory supply fittings; h) laundry tub supply fittings; i) lawn and sediment faucets; j) metering and self-closing supply fittings; and k) supply stops. 1.3 This Standard does not cover a) plumbing waste fittings, which are covered by ASME A112.18.2/CSA B125.2; b) flexible water connectors under continuous pressure, which are covered by ASME A112.18.6/CSA B125.6; c) pipes and tubes or pipe and tube fittings; d) flushometer valves which are covered by ASSE 1037/ASME A112.1037/CSA B125.37; e) anti-siphon fill valves which are covered by ASSE 1002/ASME A112.1002/CSA B125.12; f) automatic temperature-limiting devices which are covered by ASSE 1070/ASME A112.1070/CSA B125.70; and g) supply line stops which are covered in ASME A112.4.14/CSA B125.14. 1.4 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. 1.5 SI units are the units of record in Canada. In this Standard, the inch/pound units are shown in parentheses. The values stated in each measurement system are equivalent in application; however, each system is to be used independently. Combining values from the two measurement systems can result in non- conformance with this Standard. All references to gallons are to U.S. gallons. For information on the conversion criteria used in this Standard, see Annex A.