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BACKFLOW PREVENTION ASSEMBLY TESTER
TRAINING
A valve designed to open in the direction of normal flow and close with the reversal of flow. - Answers :Check valve Overflow level - Answers :The maximum height that water or liquid will rise in a receptacle before it flows over the rim. Backflow - Answers :A hydraulic condition, caused by a difference in pressures, in which non-potable water or other fluids flow into a potable water system. RPBP - Answers :A shortened name for a reduced pressure backflow preventer Air Gap - Answers :In plumbing, the unobstructed vertical distance through the free atmosphere between the lowest opening from any pipe or outlet supplying water to a tank, plumbing fixture, or other container, and the overflow rim of that container Feed water - Answers :Water that is added to a commercial or industrial system and subsequently used by the system, such as water that is fed to a boiler to produce steam. Pressure vacuum breaker - Answers :A device designed to prevent backsiphonsge, consisting of one independently operating spring-loaded check valve and an independently operating spring-loaded air-inlet valve. Bypass - Answers :In cross-connection control, any pipe arrangement that passes water around a protective device, causing it to be ineffective. Back pressure - Answers :A backflow condition in which a pump, elevated tank, boiler or other means results in a downstream pressure greater than the supply pressure Cross connection - Answers :Any arrangement of pipes, fitting, fixtures, or devices that connects a non potable system to a potable water system Atmospheric vacuum breaker - Answers :A mechanical device consisting of a float check valve and an air inlet port designed to prevent backsiphonage Double Check Valve Assembly - Answers :A testable mechanical device consiting of two independently operating, spring-loaded check valves Potable - Answers :Water that is safe for human consumption
Backflow - Answers :The reversal of the normal direction of flow Backpressure - Answers :An elevation of pressure in the downstream piping system above the supply pressure Backsiphonage - Answers :Reduction in system pressure which causes a sub atmospheric pressure to exist at a site in the water system Cross-connection - Answers :A link between potable and non-potable sources Potable water - Answers :Chemically, biologically, radiologically safe, aesthetically pleaseing Backflow prevention - Answers :Installed for containment and isolation Containment - Answers :Service protection (protects mains from property) Isolation - Answers :Internal protection (isolates each internal area). Sewage - Answers :Can be chemical, biological, or both Force - Answers :A vector that tend to produce an acceleration of a body in the direction of its application Force - Answers :Provides energy for motion Weight - Answers :Type of force resulting from gravity Force - Answers :Measured in lbs Area - Answers :The extent of a planar region or the surface of a solid measured in square units Area - Answers :Measures the surface of an object Area - Answers :Tells how big something is Area - Answers :Measures in square inches (in2) Pressure - Answers :Force applies uniformly across a surface Pressure - Answers :=force/area Pressure - Answers :Tells how much weight over how big a surface area Pressure - Answers :Measured in lbs/in2 (psi)
Reduced pressure zone backflow preventer - Answers :A mechanical device consisting of two independnetly operating, spring-loaded check valves with a reduced pressure zone between check valves. Auxiliary supply - Answers :Any water source or system, other than the potable water supply, that may be available in the building or premesis. Actual Cross Connection - Answers :Any arrangement of pipes, fittings, that connects a potable water supply directly to a non-potable source at all times. Barometric Loop - Answers :Only for backsiphonage protection. Cannot protect for backpressure. Backlfow - Answers :Undesirable reversal of flow of water or other substances into the potable water distribution supply. Back pressure - Answers :Pressure in downstream piping greater than supply pressure Backsiphonage - Answers :Sub atmospheric pressure in the water system. Cross connection - Answers :An actual or potential connection between a potable water supply and any non-potable substance. Direct cross connection - Answers :Subject backpressure or backsiphonage Indirect cross connection - Answers :Subject to backsiphonage only Pollutant - Answers :Non-health hazard (does not cause illness or death) Contaminant - Answers :Health hazard (can cause illness or death) 27 3/4 - Answers :2.31 feet of head Backflow - Answers :The undesirable reversal of flow of water or other substances into the potable water distribution supply. Backpressure and backsiphonage - Answers :Backflow occurs because of what two things Backpressure - Answers :Pressure in the downstream piping becomes higher than supply (upstream) pressure driving water the wrong way. Backsiphonage - Answers :Sub atmospheric pressure Cross connection - Answers :An actual or potential connection between a potable water supply and any non potable substance or source
Direct and indirect - Answers :2 types of cross connections Direct cross connection - Answers :Subject to backpressure or backsiphonage Indirect cross connection - Answers :Subject to backsiphonage only Aspirator/Venturi effect - Answers :Condition where undersized water pipes carry water under a high velocity past or through a small opening and will cause a backsiphonage effect. Non health hazard and health hazard - Answers :2 degrees of hazard Pollutant - Answers :Non health hazard, low hazard, and will not cause illness or death. Contaminant - Answers :Health hazard, high hazard, and causes illness or death. Five means of preventing backflow - Answers :Air gap seperation, reduced pressure principle Assembly, double check valve Assembly, pressure vacuum breaker, atmospheric vacuum breaker. Airgap - Answers :2x Supply line diameter but not less than 1". Approved airgap seperation - Answers :Backsiphonage, backpressure, containment, and pollutant Reduced pressure principle assembly (RP) - Answers :Backsiphonage, Backpressure, contaminant, and polutant Double Check Valve Assembly - Answers :Does not prevent against contaminant, but does prevent against backsiphonage, backpressure, and pollutants Proper installation for DC and RP - Answers :Minimum 12" above grade, maximum 36" above grade, accessibility for testing and repair, and weather/vandalism protection (if needed) with adequate drainage. Proper installation for DC and RP - Answers :Double check valve assemblies and reduce pressure backflow preventers should be installed vertically, if they have been specifically approved for vertical orientation. Pressure Vacuum Breaker (PVB) - Answers :Must be installed 12" above grade Pressure Vacuum Breaker (PVB) - Answers :Does not protect against backpressure, but will protect against backsiphonage, contaminants, and pollutants.
4 preliminary steps to testing - Answers :Notify, identify, inspect, or observe. Relief valve - Answers :Must open at 2 PSID Relief valve check valve 1 - Answers :Hold relief +3 PSID Relief valve check valve 2 - Answers :Must hold against back pressure Relief valve check valve 2 - Answers :If tested must hold 1 PSID Reduced Pressure Backflow Preventer - Answers :An assembly containing two independently acting approved check valves together with a hydraulically operating, mechanically independent pressure differential relief valve located between the check valves and at the same time below the first check valve. Reduced Pressure Backflow Preventer - Answers :Installed 12-36" above grade Reduced Pressure Backflow Preventer - Answers :Adequate clearance above and to the sides of the unit repair must be 12" on backside and 24" on testcock side. Reduced Pressure Backflow Preventer - Answers :Protects against backsiphonage, backpressure, high, and low hazards. Reduced Pressure Backflow Preventer - Answers :Must be tested after installation, whenever it is cleaned or repaired, and at least annually. 3 methods for testing check valves - Answers :1. Seating with backpressure
- Seating with flow
- Differential (PSID) Seating with back pressure - Answers :Check valve must close Seating with back pressure - Answers :High-pressure water routed around assembly through the bypass hose Seating with back pressure - Answers :Associated with disk compression Seating with back pressure - Answers :Check valve must hold tight Disk compression - Answers :Pressure applied to backside of the valve may compress the resilient disk Disk compression - Answers :Zone pressure may increase Disk compression - Answers :Pressure differential may decrease
Disk compression - Answers :Watch for zone pressure to drop to the relief valve to opening point Seating with flow - Answers :Valve closes under normal conditions Seating with flow - Answers :From high to low pressure (direction of flow) Seating with flow - Answers :High and low hoses are connected across a specific valve Seating with flow - Answers :Usually indicates whether the valve closes under normal conditions Differential (PSID) - Answers :A component of test # 2 Differential (PSID) - Answers :Evaluation of how well the valve closes
- how strong the spring is
- how easliy the valve moves in the guide Pass - Answers :Valves holding backpressure Fail - Answers :Valve leaking under backpressure Fail - Answers :Valve leaking under normal flow 1 PSID - Answers :Minimum standards for passing check valve Expansion tank - Answers :A means of controlling increased pressure on a household Dual check - Answers :Non testable and located behind meter 4,3,2,1 - Answers :Flush test cocks in this sequence Double Check Valve Backflow Prevention Assembly (DC) - Answers :Check valve 1 and. 2 must hold at 1 PSID or higher Double Check Valve Backlfow Preventer - Answers :An assembly composed of two independently acting, approved check valves, including tightly closing resilient sealed shutoff valves attached at each end of the assembly and fitted properly located resilient seated test cocks. Double Check Valve Backlfow Preventer - Answers :Must be installed 12-36" above grade
Atmospheric Vacuum Breaker - Answers :Protects against backsiphonage, high hazard, and low hazard only. Atmospheric Vacuum Breaker - Answers :Recommended usage is 12 hours in any given 24 hour period. Atmospheric Vacuum Breaker - Answers :Generally not field testable, but should be inspected yearly for proper operation of the air inlet valve. Removal of the canopy may be necessary to determine free movement of the air inlet valve. Pressure Vacuum Breaker - Answers :Check valve and air inlet valve must open at 1 PSID. Pressure Vacuum Breaker - Answers :An assembly containing an independently operating internally loaded check valve and an independently operating loaded air inlet valve located on the discharge side of the checkvalve. Pressure Vacuum Breaker - Answers :Must be installed with a minimum of 12" clearance above the overfloe rim. Pressure Vacuum Breaker - Answers :Mounted in a vertical upright position. Pressure Vacuum Breaker - Answers :All water use downstream should be considered non-potable Pressure Vacuum Breaker - Answers :No downstream pumps. Pressure Vacuum Breaker - Answers :Canopy should be in place while the unit is in operation and it should be removed for testing purposes. Pressure Vacuum Breaker - Answers :Resilient seated test cocks provided for field testing. Pressure Vacuum Breaker - Answers :Resilient seated shut offs attached at each end of the assembly. Pressure Vacuum Breaker - Answers :Protects against backsiphonage, low hazard and high hazard only. Spill Resistant Pressure Vacuum Breaker - Answers :This assembly has one test cock. Pressure Vacuum Breaker - Answers :The #1 test cock is located after the #1 shut off. Pressure Vacuum Breaker - Answers :Must be installed 12" above the highest downstream point.
