scope:

Description

This standard covers design and performance requirements for water supply system wall hydrants. These units shall have a permanent means including atmospheric vent valve(s), to prevent backflow due to backsiphonage and back pressure less than three (3) meters (10 feet) of head pressure from a potential health hazard. The device shall only be used on systems where the only source of back pressure comes from an elevated hose equal to or less than 3 meters (10 feet) in height. The units shall be classified as follows:

(a) Type A: These hydrants drain the water when the water supply is shut off and the hose removed to prevent damage from freezing.

(b) Type B: These hydrants automatically drain water with a hose attached, end nozzle closed, and the hydrant valve closed.

Size Range

Sizes shall include 13 mm, 19 mm and 25 mm (1/2", 3/4", and 1") male hose threaded outlets.

Pressure Range

The hydrants shall be designed for a minimum operating pressure of 862 kPa (125 p.s.i.).

Temperature Range

The hydrants shall be designed for flow temperatures of 0.6 degrees C to 60 degrees C (33 degrees F to 140 degrees F).

Connections

Outlet

Garden hose connection threads shall be 19 mm or 25 mm (3/4" or 1") garden hose couplings per ANSI B1.20.7.

Inlet

Sizes shall include but not be limited to 13 mm, 19mm or 25 mm (1/2", 3/4", or 1").

Installation and Service

Hydrants shall be designed and built such that, after installation, servicing of the elastomeric parts shall be accomplished using standard tools. Construction shall permit field service without damage or marring the significant surface of the hydrant, without removing the hydrant from service.

Atmospheric Vent

Opening Area, anti-siphon Device. The least total cross-sectional area of the air flow ways, including the seat area of the air vent valve, shall not be less than the least total cross-sectional area of the waterflow passage or passages upstream from the air vent valve. Atmospheric vent port(s) shall be of a nonstandard plumbing connection.

Assembly drawings and other data which are needed to enable a testing agency to determine compliance with this standard, shall accompany assemblies when submitted for examination and performance tests under this standard.

Application

The purpose of these hydrants is to supply potable water without danger of damage to the hydrant due to freezing: and to provide protection of the potable water supply from contamination due to backsiphonage or back pressure less than or equal to three (3) meters (10 feet) of head pressure.