ANSI/CAN/UL/ULC 331:2023

1 Scope 1.1 These requirements cover complete, self-contained strainer or filter assemblies intended for use with designated flammable and combustible liquids, anhydrous ammonia (fertilizer grade), and non-potable water. Flammable and combustible liquid strainers or filter assemblies are used in residential and commercial fuel-burning, dispensing, and handling facilities. Although these devices are designated as strainers, they may be either strainers or filters according to the common terminology of the industry. 1.2 The term flammable and combustible liquids as used in this standard means fuel oil, gasoline, kerosene, and similar petroleum products, liquefied petroleum gas (LP-Gas or propane), and manufactured and natural fuel gas. 1.3 These requirements do not cover the following: a) Strainers for handling liquids under cryogenic conditions; b) Strainers for marine use; c) Strainers for automotive fuel lines; d) Strainers for handling refrigerants; e) Strainers for use in such facilities as chemical, petrochemical, petroleum, and utility power plants; f) Strainers for use in fluid-power (hydraulic and pneumatic) applications; g) Strainers for use with gasoline or gasoline/ethanol blends, which are covered under the Standard for Strainers for Gasoline and Gasoline/Ethanol Blends with Nominal Ethanol Concentrations up to 85 Percent (E0 – E85), UL 331A; and h) Strainers for use with diesel fuel, biodiesel fuel, diesel/biodiesel blends, kerosene, or fuel oil, which are covered under the Standard for Strainers for Diesel Fuel, Biodiesel Fuel, Diesel/Biodiesel Blends with Nominal Biodiesel Concentrations Up to 20 Percent (B20), Kerosene, and Fuel Oil, UL 331B. 1.4 Requirements for strainers for non-potable water are provided in Annex A. 1.5 Products covered by this Standard are intended to be installed and used in accordance with the applicable Codes and Regulations as determined by the Authority Having Jurisdiction (AHJ), such as, but not limited to: a) In the United States: 1) Flammable and Combustible Liquids Code, NFPA 30; 2) Code for Motor Fuel Dispensing Facilities and Garages, NFPA 30A; et 3) Standard for the Installation of Oil-Burning Equipment, NFPA 31. b) In Canada: 1) The National Fire Code of Canada; 2) Installation Code for Oil Burning Equipment, CSA B139; and 3) Provincial or other Regulations. 2 Components 2.1 Except as indicated in 2.2, a component of a product