UL 312:2018-03 Check Valves for Fire-Protection Service.
1.1 These requirements cover check valves of 1 NPS and larger, used in piping systems supplying water for fire protection service.
1.2 The check valves covered by these requirements are intended for installation and use in accordance with the Standards for:
a) Low-, Medium-, and High-Expansion Foam, NFPA 11;
b) Installation of Sprinkler Systems, NFPA 13;
c) Installation of Standpipe and Hose Systems, NFPA 14;
d) Water Spray Fixed Systems for Fire Protection, NFPA 15;
e) Installation of Foam-Water Sprinkler and Foam-Water Spray Systems, NFPA 16;
f) Installation of Stationary Pumps For Fire Protection, NFPA 20;
g) Water Tanks for Private Fire Protection, NFPA 22;
h) Installation of Private Fire Service Mains and Their Appurtenances, NFPA 24;
i) Water Mist Fire Protection Systems, NFPA 750; and
j) Installation of Sprinkler Systems in Residential Occupancies Up to and Including Four Stories in Height, NFPA 13R.
2.1 Except as indicated in 2.2, a component of a product covered by this standard shall comply with the
requirements for that component.
2.2 A component is not required to comply with a specific requirement that:
a) Involves a feature or characteristic not required in the application of the component in the product covered by this standard, or
b) Is superseded by a requirement in this standard.
2.3 A component shall be used in accordance with its rating established for the intended conditions of use.
2.4 Specific components are incomplete in construction features or restricted in performance capabilities. Such components are intended for use only under limited conditions, such as certain temperatures not exceeding specified limits, and shall be used only under those specific conditions.
3 Units of Measurement
3.1 Values stated without parentheses are the requirement. Values in parentheses are explanatory or
4 Undated References
4.1 Any undated reference to a code or standard appearing in the requirements of this standard shall be
interpreted as referring to the latest edition of that code or standard.
5.1 For the purposes of this standard, the following definitions apply.
5.1.1 CHECK VALVE — A self- acting device that is designed to allow fluid flow in one direction.
5.1.2 DETECTOR CHECK VALVE — A check valve equipped with a bypass around the valve to allow relatively small flows without operation of the valve. The bypass allows installation of a water meter to record a small usage of water.
5.1.3 NPS (NOMINAL PIPE SIZE) — A dimensionless designator for pipe sizes used to replace terms such as “nominal diameter” and “nominal size”. Defined in standards including in the:
a) Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless, ASTM A 53/A 53M;
b) Standard Specification for Electric-Resistance-Welded Steel Pipe, ASTM A 135/A 135M; and
C) Standard Specification for Black and Hot-Dipped Zinc-Coated (Galvanized) Welded and Seamless Steel Pipe for Fire Protection Use, ASTM A 795/A 795M.UL 312 pdf download.