scope:

This standard encompasses the design and performance requirements for 2, 2-1/2, 3, 3-1/2, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, and 24 inch nominal size anti-water hammer check valves. The intended application of these devices is to permit the flow of water in one direction only, preventing flow in the opposite direction, as well as to moderate the potentially destructive effects of pressure surges or water hammer due to pump starting and stopping and valve opening and closing. Sizes refer to the nominal diameter of the pipeline to which the valve will be connected. In cases where metric sized anti-water hammer check valves are to be examined for FM Approval, test criteria comparable to the equivalent or nearest nominal inch size shall be used.

This standard defines the requirements for anti-water hammer check valves with single or multiple waterways. Anti-water hammer check valves covered in this Approval standard are supplied with flanged, grooved, threaded or wafer style end connections. Other types of anti-water hammer check valves may be FM Approved if they meet the requirements and intent of this standard. Anti-water hammer check valves of unusual design may be subjected to special tests to determine their suitability.

This standard encompasses the design and performance requirements for anti-water hammer check valves for their intended installation in the discharge line of a fire pump where conditions may be expected to cause pressure surges or water hammer.

Purpose

This standard states Approval criteria for anti-water hammer check valves for fire protection systems.

Approval criteria include, but are not limited to, performance requirements, marking requirements, examination of manufacturing facility(ies), audit of quality assurance procedures, and a surveillance audit program.

Approval standards are intended to verify that the product described shall meet stated conditions of performance, safety, and quality useful to the ends of property conservation.