UL 331A

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Strainers for Gasoline and Gasoline/Ethanol Blends with Nominal Ethanol Concentrations Up to 85 Percent (E0 - E85)
UL 331A
1 Scope

1.1 These requirements cover complete, self-contained strainer or filter assemblies intended for use with fuels designated in 1.2. Although these devices are designated strainers, they may be either strainers or filters according to the common terminology of the industry.

1.2 Strainers and filter assemblies covered by these requirements are intended for use with one or more of the following:

• a) Gasoline formulated in accordance with the Standard Specification for Automotive Spark Ignition Fuel, ANSI/ASTM D4814;
• b) Gasoline/ethanol blends with nominal ethanol concentrations up to 25 percent ethanol (E25), consisting of gasoline formulated in accordance with the Standard Specification for Automotive Spark Ignition Fuel, ANSI/ASTM D4814, when blended with denatured fuel ethanol formulated to be consistent with the Standard Specification for Denatured Fuel Ethanol for Blending With Gasolines For Use as Automotive Spark Ignition Engine Fuel, ANSI/ASTM D4806; or
• c) Gasoline/ethanol blends with nominal ethanol concentrations above 25 percent formulated in accordance with the Standard Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark Ignition Engines, ANSI/ASTM D5798.

1.3 These requirements do not cover:

• 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 or filter assemblies for use with diesel, biodiesel, diesel/biodiesel blends, fuel oil, or kerosene which are covered under the Outline of Investigation 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.
• h) Strainers or filter assemblies for use with LP-Gas, Natural Gas, Manufactured Gas, and Anhydrous Ammonia, which are covered under the Standard for Strainers for Flammable Fluids and Anhydrous Ammonia, UL 331.