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1. Which device is designed to prevent backflow caused by
backpressure?
A. Air gap
B. Double check valve assembly
C. Vacuum breaker
D. Pressure reducing valve
Rationale: A double check valve assembly prevents backflow caused
by both backpressure and back-siphonage.
2. What is the primary purpose of a backflow preventer?
A. Reduce water pressure
, B. Increase water flow
C. Protect potable water from contamination
D. Control water temperature
Rationale: The main function of backflow preventers is to stop
contaminants from entering the public water supply.
3. Which type of backflow preventer must be installed in areas with high
hazard risks?
A. Double check valve
B. Reduced pressure zone assembly
C. Atmospheric vacuum breaker
D. Pressure vacuum breaker
Rationale: Reduced pressure zone (RPZ) assemblies are required in
high-hazard conditions because they provide the highest level of
protection.
4. What does “back-siphonage” refer to?
A. Water leaking from a pipe
B. Flow of water from a contaminated source into the potable water
supply due to negative pressure
C. Excess water pressure
D. Water freezing in a pipe
Rationale: Back-siphonage occurs when a negative pressure draws
contaminated water into the potable system.
,5. A test cock on a backflow assembly is used for:
A. Draining the system
B. Testing assembly performance
C. Increasing flow rate
D. Relieving pressure
Rationale: Test cocks allow testers to attach gauges and verify that
the assembly is functioning correctly.
6. How often must a backflow preventer be tested in most jurisdictions?
A. Monthly
B. Annually
C. Every 12 months or as required by local codes
D. Every 5 years
Rationale: Regular annual testing ensures the device maintains its
protective function.
7. Which of the following is considered a high-hazard situation?
A. Irrigation systems
B. Fire sprinkler systems
C. Chemical processing systems
D. Residential water lines
Rationale: High-hazard situations involve substances that could
cause serious health risks if backflow occurs.
8. What is the maximum allowable differential pressure across a double
check valve during normal operation?
, A. 1 psi
B. 2 psi
C. 5 psi
D. 10 psi
Rationale: Most standards allow up to 5 psi differential across a
double check valve during normal operation.
9. Which assembly requires relief valve testing?
A. Double check valve
B. Reduced pressure zone assembly
C. Atmospheric vacuum breaker
D. Pressure vacuum breaker
Rationale: RPZ assemblies include a relief valve that must be tested
for proper operation.
10. What is the proper orientation for installing a reduced pressure
zone (RPZ) assembly?
A. Horizontally only
B. According to manufacturer instructions, typically horizontal with
flow arrow in direction of water flow
C. Upside down
D. Vertically only
Rationale: RPZ assemblies must follow manufacturer guidelines to
ensure correct operation and testability.