scope:

This standard covers the reduced-pressure principle backflow prevention assembly. The assembly shall be capable of withstanding a working water pressure of at least 150 psi (1,034 kPa) without damage to working parts or impairment of function and for operation on hot or cold water lines.

This standard covers hot and cold water reduced-pressure principle backflow prevention assemblies. All assemblies shall be designed to, at a minimum, operate at a temperature range of 33°F to 140°F (1°C to 60°C). Hot water assemblies shall be designed to, at a minimum, operate in water at a temperature range of 33°F to 180°F (1°C to 82°C).

A complete assembly consists of a mechanical, independently operating, hydraulically dependent relief valve located between two independently operating, internally loaded check valves that are located between two tightly closing resilient-seated shutoff valves with four properly placed (see Sec. 4.3.1.8) resilient-seated test cocks.

Purpose

The purpose of this standard is to provide the minimum requirements for reduced-pressure principle backflow prevention assemblies, including materials, general and detailed design, workmanship, and shipping and delivery.