Purpose - To prevent backflow or back-siphonage into a potable water distribution system when installed with the Critical Level point (as described later herein) at least 6 inches above the flood level rim of the receptacle served or greatest elevation of use, and when installed on the discharge side of the last control valve, and the backflow source is subject to no more than normal atmospheric pressure. This device shall not be subjected to more than twelve (12) hours of continuous water pressure.
The purpose of this device is to reduce static and flowing pressures in water distribution systems. Description Devices covered by this standard are self-contained, direct acting, single diaphragm types. Devices shall be permitted to have an integral strainer, separate strainer connected to the valve inlet, or be without strainer. Devices shall be permitted to be with or without an integral by-pass relief valve. Size Range Connection pipe sizes shall be 15 DN, 20 DN, 25 DN, 32 DN, 40 DN, 50 DN, 65 DN and 80 DN (1/2 NPT, 5/8 NPT, 1 NPT, 1-1/4 NPT, 1-1/2 NPT, 2 NPT, 2-1/2 NPT and 3 NPT) per the ASME Standard B.1.20.1. Pressure Range Devices shall be designed for a minimum working pressure of 1724 kPa (250 psi). Temperature Range The devices shall be designed for temperatures of 0.6 degrees C (33 degrees F) to 60 degrees C (140 degrees F) minimum.
This standard applies to food waste grinders designed and intended for use in food establishments, supplied with water and which discharges waste into a plumbing drainage system. Purpose This standard is intended to indicate the criteria for performance of the commercial food waste grinders. NOTE: Commercial food waste grinder units are furnished in several distinct types; and the criteria in this standard are applicable to all types.
Water hammer arresters are installed on water distribution system piping to prevent over pressures within water distribution systems, thereby prolonging the service life of valves, piping, fittings, trim, equipment, appliances, appurtenances, and other devices which are part of the distribution system; and to eliminate noise. This standard addresses the test methods and performance requirements for water hammer arresters. Description This standard applies only to those devices classified as water hammer arresters having a permanently sealed cushion of water or gas isolated from the water way, and designed to provide continuous protection, without maintenance, against detrimental surge pressures within the water distribution system. Size Range The size of water hammer arresters shall be within the range from Type AA which are used for "point of use " residential appliance applications to Types A to F which are used in applications as defined within Table 1 of this standard. Pressures Hydrostatic Pressure Water hammer arresters shall be designed to withstand a maximum rated pressure of 1034 kPa (150 p.s.i.). Operating Pressure Water hammer arresters shall be designed for a flowing pressure up to 414 kPa (60 p.s.i.). Temperature Range Water hammer arresters shall be capable of performing in the temperature range from 0.55 degrees C (33 degrees F) to 82 degrees C (180 degrees F).
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. 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.
Pressure vacuum breaker assemblies are for installation in water supply lines to prevent the entrance of non-potable material into the potable water supply by backsiphonage only. It is not for use in any system where backpressure can be applied to the assembly. When a supply pressure is between 7 to 14 kPa (1 to 2 p.s.i.), the air inlet valve is open and the assembly will continuously discharge. Due to this probability of water discharge from the atmospheric air inlet valve, the assembly shall only be installed where water discharge does not cause damage. Description Vacuum breakers, other than air gaps, shall be classified into four general types: a. Atmospheric Type (See ASSE Standard num1001) b. Pressure Type (ASSE num1020, as described in this standard); c. Back Siphonage (See ASSE Standard num1056); and d. Pressure Type (See ASSE num1058). Size Range The assembly shall be designed to accommodate nominal pipe sizes 15 to 50 mm (1/2 " to 2 " inches). Working Pressure Range Assemblies shall be designed for a minimum rated working pressure of at least 1034 kPa (150 p.s.i). Temperature Range a. Cold water service shall range from 0.55 degrees C to 43 degrees C (33 degrees F to 110 degrees F). b. Hot water service shall range from 0.55 degrees C to 82.2 degrees C (33 degrees F to 180 degrees F) minimum.