As used in this Part 1, the following terms shall have the meanings
indicated:
A physical break between a supply pipe and a receiving vessel. The
air gap shall be at least double the diameter of the supply pipe, measured
vertically above the top rim of the vessel, in no case less than one inch.
A check valve that seats readily and completely. It must be carefully
machined to have free moving parts and assured watertightness. The face of
the closure element and valve seat must be bronze composition, or other noncorrodible
material which will seat tightly under all prevailing conditions of field
use. Pins and bushings shall be of bronze or other noncorrodible, nonsticking
material, machined for easy, dependable operation. The closure element, e.g.,
clapper, shall be internally weighted or otherwise internally equipped to
promote rapid and positive closure in all sizes where this feature is obtainable.
The term "approved double check valve assembly" means an assembly of
at least two independently acting check valves, including tightly closing
shutoff valves on each side of the check valve assembly and suitable leak-detector
drains plus connections available for testing the watertightness of each check
valve.
This device must be approved as a complete assembly.
A device incorporating two or more check valves and an automatically
operating differential relief valve located between the two checks, two shutoff
valves, and equipped with necessary appurtenances for testing. The device
shall operate to maintain the pressure in the zone between the two check valves,
less than the pressure on the public water supply side of the device.
At cessation of normal flow, the pressure between check valves shall
be less than the supply pressure. In case of leakage of either check valve,
the differential relief valve shall operate to maintain this reduced pressure
by discharging to the atmosphere. When the inlet pressure is two pounds per
square inch or less, the relief valve shall open to the atmosphere, thereby
providing an air gap in the device. To be approved, these devices must be
readily accessible for maintenance and testing and installed in a location
where no part of the valve will be submerged, the enclosure must be self-draining,
so that the large amount of water which the relief valve may vent will be
disposed of reliably without submergence of the relief valve.
This device must also be approved as a complete assembly.
Any water supply approved by the State of New York Department of
Health.
Any water supply on or available to the premises other than the approved
public water supply.[1]
A person who is examined annually by the Water Purveyor, and found
competent for the testing of backflow prevention devices. He shall be provided
with an appropriate identification card which must be renewed annually. Failure
to perform his duties competently and conscientiously will result in prompt
withdrawal of his certification.
The Southern Cayuga Lake Intermunicipal Water Commission created
by an intermunicipal agreement among the Town of Ithaca and several other
municipalities.
[2]Any unprotected connection between any part of a water system used
or intended to supply water for drinking purposes and any source or system
containing water or substance that is not or cannot be approved as equally
safe, wholesome, and potable for human consumption.
A vacuum breaker which is designed so as not to be subjected to static
line pressure.
A vacuum breaker designed to operate under conditions of static line
pressure.
The consumer or person on the premises charged with the responsibility
of complete knowledge and understanding of the water supply piping within
the premises and for maintaining the consumer's water system free from cross-connections
and other sanitary defects, as required by regulations and laws.
