Backflow Prevention Practice Exam Questions
with Correct Answers 2026-2027 100% Pass
1. Containing a plumbing system from the public water supply requires backflow protection
at the ?
A. Appliance or fixture
B. Building foundation
C. Irrigation system
D. Service Connection
E. Sprinkler riser - CORRECT ANSWER -Service Connection
2. Backflow preventer manufacturers recommend that assemblies be field-
tested annually and when ?
A. Installed
B. Moved
C. Repaired or Installed
D. Shut down
E. Water suppliers provide notice - CORRECT ANSWER -Repaired or Installed
3. A differential pressure gauge reading of 0.2 psid is represented on water column sight tu
be by ?
A. 1/16 in. (0.16 cm)
B. 1/2 in. (1.3 cm)
C. 2 in. (5.1 cm)
D. 3.5 in. (8.9 cm)
E. 5.5 in. (14 cm) - CORRECT ANSWER -5.5 in. (14 cm)
4. Pollution of a public water supply suggests the substance in the water is ?
A. Aesthetically bad
B. Biological with virus only
C. Lowering the pH below 1.4
D. Radiological
E. Toxic - CORRECT ANSWER -Aesthetically bad
,5. Backsiphonage may occur when the pressure inside copper tubing is ?
A. Greater than atmospheric pressure
B. Greater than barometric pressure
C. Greater than 0 gauge pressure
D. Less than absolute pressure
E. Less than atmospheric pressure - CORRECT ANSWER -
Less than atmospheric pressure
6. A cross-connection may be a permanent piping arrangement or a(n) ?
A. Backflow preventer
B. Church symbol
C. OSHA hazardous area designation
D. Railroad and highway intersection sign
E. Temporary hose bibb connection - CORRECT ANSWER -
Temporary hose bibb connection
7. The isolation of a plumbing water system hazard requires ?
A. Appliance protection
B. Building quarantine
C. High-hazard protection
D. Meter protection
E. Toxin monitoring - CORRECT ANSWER -Appliance protection
8. A direct cross-connection suggests the piping system may be subjected to ?
A. Backpressure or backsiphonage
B. Backsiphonage only
C. Periodic inspection
D. Sustained pressure
E. Toxic materials - CORRECT ANSWER -Backpressure or backsiphonage
9. A pipe restriction's flow velocity increase may allow ?
A. Aspiration
B. Backpressure
, C. Low turbulence
D. Pressure head
E. Pressure surges - CORRECT ANSWER -Aspiration
10. Water supply contamination from backflow may result in ?
A. A bad taste
B. Coloration
C. Death
D. Odor or smell
E. Pipe wall mineral deposit flaking - CORRECT ANSWER -Death
11. To prevent backflow, an atmospheric vacuum breaker is primarily designed to ?
A. Allow air into the outlet piping system
B. Create an elevation loop above ground
C. Introduce head loss
D. Prevent backpressure
E. Restrict velocity - CORRECT ANSWER -Allow air into the outlet piping system
12. Atmospheric vacuum breakers will typically be located on ?
A. Commercial irrigation systems
B. Fire-suppression systems
C. Plumbing fixtures or appliances
D. Utility storage tanks
E. Water service connections - CORRECT ANSWER -Plumbing fixtures or appliances
13. The mechanical component of an atmospheric vacuum breaker serves as an air-
inlet valve and a ?
A. Check valve
B. Regulating valve
C. Relief valve
D. Shut-off valve
E. Test port - CORRECT ANSWER -Check valve
with Correct Answers 2026-2027 100% Pass
1. Containing a plumbing system from the public water supply requires backflow protection
at the ?
A. Appliance or fixture
B. Building foundation
C. Irrigation system
D. Service Connection
E. Sprinkler riser - CORRECT ANSWER -Service Connection
2. Backflow preventer manufacturers recommend that assemblies be field-
tested annually and when ?
A. Installed
B. Moved
C. Repaired or Installed
D. Shut down
E. Water suppliers provide notice - CORRECT ANSWER -Repaired or Installed
3. A differential pressure gauge reading of 0.2 psid is represented on water column sight tu
be by ?
A. 1/16 in. (0.16 cm)
B. 1/2 in. (1.3 cm)
C. 2 in. (5.1 cm)
D. 3.5 in. (8.9 cm)
E. 5.5 in. (14 cm) - CORRECT ANSWER -5.5 in. (14 cm)
4. Pollution of a public water supply suggests the substance in the water is ?
A. Aesthetically bad
B. Biological with virus only
C. Lowering the pH below 1.4
D. Radiological
E. Toxic - CORRECT ANSWER -Aesthetically bad
,5. Backsiphonage may occur when the pressure inside copper tubing is ?
A. Greater than atmospheric pressure
B. Greater than barometric pressure
C. Greater than 0 gauge pressure
D. Less than absolute pressure
E. Less than atmospheric pressure - CORRECT ANSWER -
Less than atmospheric pressure
6. A cross-connection may be a permanent piping arrangement or a(n) ?
A. Backflow preventer
B. Church symbol
C. OSHA hazardous area designation
D. Railroad and highway intersection sign
E. Temporary hose bibb connection - CORRECT ANSWER -
Temporary hose bibb connection
7. The isolation of a plumbing water system hazard requires ?
A. Appliance protection
B. Building quarantine
C. High-hazard protection
D. Meter protection
E. Toxin monitoring - CORRECT ANSWER -Appliance protection
8. A direct cross-connection suggests the piping system may be subjected to ?
A. Backpressure or backsiphonage
B. Backsiphonage only
C. Periodic inspection
D. Sustained pressure
E. Toxic materials - CORRECT ANSWER -Backpressure or backsiphonage
9. A pipe restriction's flow velocity increase may allow ?
A. Aspiration
B. Backpressure
, C. Low turbulence
D. Pressure head
E. Pressure surges - CORRECT ANSWER -Aspiration
10. Water supply contamination from backflow may result in ?
A. A bad taste
B. Coloration
C. Death
D. Odor or smell
E. Pipe wall mineral deposit flaking - CORRECT ANSWER -Death
11. To prevent backflow, an atmospheric vacuum breaker is primarily designed to ?
A. Allow air into the outlet piping system
B. Create an elevation loop above ground
C. Introduce head loss
D. Prevent backpressure
E. Restrict velocity - CORRECT ANSWER -Allow air into the outlet piping system
12. Atmospheric vacuum breakers will typically be located on ?
A. Commercial irrigation systems
B. Fire-suppression systems
C. Plumbing fixtures or appliances
D. Utility storage tanks
E. Water service connections - CORRECT ANSWER -Plumbing fixtures or appliances
13. The mechanical component of an atmospheric vacuum breaker serves as an air-
inlet valve and a ?
A. Check valve
B. Regulating valve
C. Relief valve
D. Shut-off valve
E. Test port - CORRECT ANSWER -Check valve
