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BCIT STUDY BCWWA - Ultimate Study Guide
The Check Valves of a Double Check Valve Assembly must be : Correct Answer - Internally Loaded Which of the following backflow preventers offers effective protection under backsiphonage conditions only and can also be subjected to constant full line pressure? Correct Answer - Spill Resistant Type Pressure Vacuum Breaker Which of the choices is best described as " a flow of water or other liquids back into the potable water supply due to a negative or reduced pressure in the supply piping? " Correct Answer - Backsiphonage A residential " partial flow through " type fire sprinkler / standpipe system is designed to circulate water in what portion ( s ) of the water system? Correct Answer - Sprinkler system main The factory loaded spring tensions of the first and second check valves found in a Reduced Pressure Principle Backflow Assembly are always : Correct Answer - Pre - loaded different from one another An Air Gap must be : Correct Answer - Twice the pipe diameter with a minimum of 1 inch separation Upon completing test number one of a Double Check Valve Assembly , when using a differential pressure gauge in what position are the shut off valves for the next test? Correct Answer - Shutoff valve # 1 is open and shutoff valve # 2 is closed According to the AWWA Canadian CCC manual , the minimum vertical distance from the bottom of a RP's relief valve to the finished floor level should be? Correct Answer - 300 mm ( 12 " )
The Dual Check Valve can be used to isolate which one of the following applications? Correct Answer - Residential potable water systems with a minor degree of hazard Backflow prevention assemblies shall be field tested to a minimum of : Correct Answer - Annually preventers be installed before a fixed platform is to be provided below the assembly? To what maximum centerline height ( from the finished floor ) must testable backflow Correct Answer - 1500 mm ( 5 ' ) Which backflow preventer contains a float check , a check seat and an air inlet poppet? Correct Answer - Atmospheric Vacuum Breaker The Pressure Vacuum Breaker Assembly may be used for backflow protection for which of the following conditions? Correct Answer - Backsiphonage ; severe hazard How many test cocks are there on a Spill Resistant Type Pressure Vacuum Breaker Assembly? Correct Answer - One When field testing a Pressure Vacuum Breaker Assembly installed close to a ceiling , the gauge should : Correct Answer - Be placed at the same level as the assembly During the first test of a Double Check Valve Assembly , it is found that water continually runs from open test cock # 3. The bleed off valve arrangement is opened and after a moment the water stops running out of the open bleed off valve arrangement , but continues to flow from test cock # 3. What is the most probable problem? Correct Answer - Shutoff valve # 2 and check valve # 2 are leaking with backpressure The spring in the relief valve of a Reduced Pressure Principle Backflow Assembly is designed to : Correct Answer - Open the relief valve
A Lab Faucet Vacuum Breaker is effective protection against : Correct Answer - Backsiphonage Edible syrup , in a cannery , was pressurized into a drinking water line through a direct cross connection could have been prevented by the installation of a : Correct Answer - Reduced Pressure Principle Backflow Assembly The type ( s ) of backflow are : Correct Answer - Backpressure and Backsiphonage Which of the following is part of a Cross Connection Control program? Correct Answer - Annual testing of backflow assemblies Which component of a Pressure Vacuum Breaker assembly must be field tested first? Correct Answer - The air inlet valve A field test being performed on a Double Check Valve Assembly using a differential pressure gauge. Water continuously flows from the open test cock # 3. What could be the problem? Correct Answer - Shutoff valve # 1 is leaking A differential pressure gauge is used to field test : Correct Answer - Reduced Pressure Principle Backflow Assembly Which of the following will provide the highest degree of backflow protection? Correct Answer - Approved Air Gap Which of the following backflow prevention device ( s ) contains two force biased , soft seated check valves? Correct Answer - Dual Check Valve A water main break will most likely cause what type of condition? Correct Answer - Backsiphonage
Which of the following instruments is used in the field testing of Double Check Valve Assemblies? Correct Answer - Differential Pressure Gauge When restoring water service to the customer , after testing a Double Check Valve Assembly , how are the shut off valve ( s ) properly opened? Correct Answer - Slowly open number two shut off valve A contaminated auxiliary water supply is utilized to maintain a fire sprinkler system at an elevated pressure. To protect the potable water supply , what is the appropriate backflow preventer on the water service pipe? Correct Answer - Reduced Pressure Principle Backflow Assembly A test is being performed on the check valve of a Pressure is noticed that shut off valve # 1 is leaking. What should the tester do? Correct Answer - Divert water through a bleed valve connected at test cock
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Internal Protection will : Correct Answer - Protect the personnel within the building When entering a vault containing a backflow prevention assembly the tester should : Correct Answer - Check the quality of the atmosphere prior to entry During a field test of a Pressure Vacuum Breaker Assembly , the air inlet valve must open : Correct Answer - At or above one psid Adequate support blocks are required for backflow prevention assemblies over ______ inch in size. Correct Answer - 2 Backflow in a public water supply can be caused by : Correct Answer
- Backpressure and Backsiphonage
A two inch Atmospheric Vacuum Breaker , when used on irrigation systems , shall be installed at least ______ inches above the downstream piping. Correct Answer - Six An increase in temperature , in a closed plumbing system , would be an example of : Correct Answer - Thermal expansion According to the CAWWA manual , what is the minimum height that a RP is to be installed , measured from the centreline of the assembly to the floor Correct Answer - 750 mm ( 30 " ) What could the tester do if shutoff valve # 1 is found to be slightly leaking during the first test of a Double Check Valve Assembly? Correct Answer - Compensate for the leaking valve by opening the bleed off valve arrangement At what minimum pressure ( psid ) must the relief valve of a Reduced Pressure Principle Assembly open , in order to pass its requirement? Correct Answer - 2. Which of the four is NOT a health hazard commonly associated with Cross Connections? Correct Answer - Physiological Hazard Who is responsible for producing and providing water that meets the quality stipulated by the Province or Territory? Correct Answer - Water Purveyor Upon the installation of a RP , the number 1 shutoff valve is opened at which time the differential pressure relief valve starts to continuously discharge. What is the most probable cause? Correct Answer - A fouled number one check valve A Full Flow Through fire sprinkler system would require which type of backflow protection? Correct Answer - No protection would be required
From the following , when must a backflow assembly be tested? Correct Answer - Backflow preventers are tested when the upstream piping has been altered From the following , which is a factor that determines the reliability of a backflow preventer? Correct Answer - Tested by an approval agency By opening the high side , then the low side control valves on a properly functioning Reduced Pressure Principle Assembly ( after attaching and bleeding the test equipment ) will cause : Correct Answer - The differential to decrease Where is it not permissible to install an Air Gap? Correct Answer - Where the atmosphere maybe contaminated Which components must be included in all testable backflow preventers? Correct Answer - Shut off valves Which backflow preventer can be subjected to continual pressure under a potential backsiphonage and backpressure condition? Correct Answer - DuC The bypass line on a double detector check valve assembly is designed to : Correct Answer - Detect unauthorized usage of water Upon completing winterizing of a testable backflow preventer , to what position are the shut - off valves to left to prevent damage? Correct Answer - Shut off # 1 full open / Shutoff # 2 half open The flood level rim of a tank was 48 " measured from floor level ; what would be the minimum installation height of the corresponding Atmospheric Vacuum Breaker? Correct Answer - 54 "
While performing a test on the Air Inlet valve of a PVB. It is noticed that the water will not stop discharging from the high side bleed valve. What is the most probable cause? Correct Answer - Leaking shutoff valve # 1 When testing a Reduced Pressure Principle Backflow Assembly : Correct Answer - The inlet shutoff valve must be open The authority having jurisdiction may require more frequent testing of backflow prevention assemblies due to : Correct Answer - High incidence of failed field test reports Pressures less than that exerted by the atmosphere is defined as a / an : Correct Answer - Vacuum During test number one of a Reduced Pressure Backflow Assembly , when the low side control valve is opened no more than one quarter turn , the needle on the gauge drops to zero and no water discharges from the relief valve. The most probable cause of the problem is a : Correct Answer - Seized relief valve A water line that is serving a sewage treatment area will require what type of backflow preventer? Correct Answer - Approved Air Gap Which backflow preventer will protect against a severe hazard in a backpressure condition? Correct Answer - Reduced Pressure Principle Backflow Assembly During test number two of a Reduced Pressure Backflow Assembly , when the bypass valve is opened , the needle on the gauge drops from 8 psid to 7 psid. What is the most probable cause? Correct Answer - Disc compression on check valve # 2 What best describes ; the practice of installing backflow prevention assemblies at the point of hazard to protect one or more actual or
potential cross connections within a premise. Correct Answer - Internal protection Should shutoff number one be found to be leaking during the first test of a Pressure Vacuum Breaker Assembly , water can be diverted through : Correct Answer - Test cock # 1 How tall must a column of water be to equal 1 psi? Correct Answer - 28 " If a DCAPC is subjected to backsiphonage , what substance would discharge from the vent? Correct Answer - Carbonated water
