194-30 DEFINITIONS
A. APPROVED: Accepted by the commissioner as meeting an applicable specification stated or cited in this regulation or as suitable for the proposed use.
B. AUXILIARY WATER SYSTEM: Any water supply on or available to the premises other than the purveyor's approved public potable water supply.
C. BACKFLOW: The flow of water or other liquids, mixtures or substances under pressure into the distribution pipes of a potable water supply system from any source other than its intended source.
D. BACKFLOW PREVENTER: A device or means designed to prevent backflow or backsiphonage. Most commonly categorized as air gap, reduced pressure principle device, double check valve assembly, pressure vacuum breaker, hose bib vacuum breaker, residential dual check, double check with intermediate atmospheric vent, and barometric loop.
1. AIR GAP: A physical separation sufficient to prevent backflow between the free-flowing discharge end of the potable water system and any other system. Physically defined as a distance equal to twice the diameter of the supply side pipe diameter but never less than one inch.
2. ATMOSPHERIC VACUUM BREAKER: A device which prevents backsiphonage by creating an atmospheric vent when there is either a negative pressure or a sub-atmospheric pressure in a water system.
3. BAROMETRIC LOOP: A fabricated piping arrangement rising at least thirty feet in the air having a "U" bend at the top and returning to the point of origin. It is utilized in water supply systems to protect against backsiphonage.
4. DOUBLE CHECK VALVE ASSEMBLY: An assembly of two independently operating spring loaded check valves with tightly closing shut-off valves on each side of the check valves, plus properly located test cocks for the testing of each check valve.
5. DOUBLE CHECK VALVE WITH INTERMEDIATE CLOSING ATMOSPHERIC VENT: A device having two spring-loaded check valves separated by an atmospheric vent chamber.
6. HOSE BIB VACUUM BREAKER: A device which is permanently attached to a hose bib and which acts as an atmospheric vacuum breaker.
7. PRESSURE VACUUM BREAKER: A device containing one or two independently operating spring-loaded check valves and an independently operated spring-loaded air inlet valve located on the discharge side of the check or checks. Device includes tightly closing shut-off valves on each side of the check valves and properly located test cocks for testing of the check valve(s).
8. REDUCED PRESSURE PRINCIPLE BACKFLOW PREVENTER: An assembly consisting of two independently operating approved check valves with an automatically operating differential relief valve located between the two check valves, tightly closing shut-off valves on each side of the check valves, plus properly located test cocks for the testing of check valves and the relief valve.
9. RESIDENTIAL DUAL CHECK: A assembly of two spring loaded independently operating check valves without tightly closing shut-off valves and test cocks. Generally employed immediately downstream of the water meter to act as a containment device.
E. BACKPRESSURE: A condition in which the Owner's system pressure is greater than the supply system pressure.
F. BACK-SIPHONAGE: The flow of water or other liquids, mixtures or substances into the distribution pipes of a potable water supply system from any source other than its intended source caused by the sudden reduction of pressure in the potable water system.
G. CITY: The City of Marlborough, Department of Public Works and Building Department, or their designee.
H. CONTAINMENT: A method of backflow prevention which requires a backflow prevention device at the water service entrance.
I. CONTAMINANT: A substance that will impair the quality of water to a degree that it creates a serious health hazard to the public leading to poisoning or the spread of disease.
J. CROSS CONNECTION: Any actual or potential connection between the public water supply and a source of contamination or pollution.
K. DEPARTMENT: The State Department of Environmental Protection.
L. FIXTURE ISOLATION: A method of backflow prevention in which a backflow preventer is located to correct a cross connection at an in-plant location rather than a water service location.
M. OWNER: Any person who has legal title to property upon which a cross connection inspection is to be made or upon which a cross connection is present.
N. PERSON: Any individual or partnership, company, public or private corporation, political subdivision or agency of the State Department, agency or instrumentality of the United States or any other legal entity.
O. PERMIT: A document issued by the Department which allows the use of a backflow preventer.
P. POLLUTANT: A foreign substance, that if permitted to get into the public water system, will degrade its quality so as to constitute moderate hazard or impair the usefulness or quality of the water to a degree which does not create an actual hazard to the public health but which does adversely and unreasonably effect such water for domestic use.
Q. WATER SERVICE ENTRANCE: That point in the owner's water system beyond the sanitary control of the City, generally considered to be the point of connection to the City water main.
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