ASSE 5110 – BACKFLOW PREVENTION
ASSEMBLY TESTER PROFESSIONAL
QUALIFICATION QUESTION AND
CORRECT ANSWERS(VERIFIED
ANSWERS) PLUS RATIONALES 2026 Q&A
INSTANT DOWNLOAD PDF
1. What is the primary purpose of a backflow prevention assembly?
A. Increase water pressure
B. Prevent water hammer
C. Prevent contamination of potable water
D. Improve water taste
Answer: C
Rationale: Backflow assemblies protect potable water systems from
contamination caused by backpressure or backsiphonage.
2. Backpressure occurs when:
A. Supply pressure drops below atmospheric
B. Downstream pressure exceeds supply pressure
C. A vacuum forms in the supply line
D. Water temperature increases
Answer: B
Rationale: Backpressure forces water to flow opposite its intended
direction due to higher downstream pressure.
3. Backsiphonage is caused by:
A. Thermal expansion
B. High downstream pressure
C. Negative pressure in the supply line
, D. Closed valves
Answer: C
Rationale: A vacuum or negative pressure can pull contaminants back into
the potable supply.
4. Which assembly provides the highest level of protection?
A. DCVA
B. PVB
C. SVB
D. RPZ
Answer: D
Rationale: Reduced Pressure Zone assemblies protect against both
backpressure and backsiphonage with high hazard applications.
5. A Double Check Valve Assembly is approved for:
A. High health hazard conditions
B. Low hazard conditions
C. Chemical systems
D. Sewage systems
Answer: B
Rationale: DCVAs are only approved where contaminants are not a health
hazard.
6. The minimum test cock size on most assemblies is:
A. 1/8 inch
B. 1/4 inch
C. 3/8 inch
D. 1/2 inch
Answer: B
Rationale: Most standards require 1/4-inch test cocks for accurate testing.
7. What device uses an air inlet valve?
A. DCVA
B. RPZ
C. AVB
D. RPDA
Answer: C
, Rationale: Atmospheric Vacuum Breakers rely on an air inlet to prevent
backsiphonage.
8. An AVB must be installed:
A. Below all outlets
B. Horizontally
C. At least 6 inches above the outlet
D. Underground
Answer: C
Rationale: Elevation is required to ensure proper air inlet operation.
9. Which assembly can be continuously pressurized?
A. AVB
B. PVB
C. SVB
D. Hose bib vacuum breaker
Answer: B
Rationale: PVBs are designed for continuous pressure, unlike AVBs.
10.Relief valve discharge on an RPZ indicates:
A. Normal operation
B. A malfunction or pressure differential issue
C. Thermal expansion only
D. Proper installation
Answer: B
Rationale: Relief valve discharge signals failure or abnormal pressure
conditions.
11.The purpose of test cocks is to:
A. Drain the system
B. Vent air
C. Allow pressure testing
D. Regulate flow
Answer: C
Rationale: Test cocks provide access points for pressure measurements
during testing.
ASSEMBLY TESTER PROFESSIONAL
QUALIFICATION QUESTION AND
CORRECT ANSWERS(VERIFIED
ANSWERS) PLUS RATIONALES 2026 Q&A
INSTANT DOWNLOAD PDF
1. What is the primary purpose of a backflow prevention assembly?
A. Increase water pressure
B. Prevent water hammer
C. Prevent contamination of potable water
D. Improve water taste
Answer: C
Rationale: Backflow assemblies protect potable water systems from
contamination caused by backpressure or backsiphonage.
2. Backpressure occurs when:
A. Supply pressure drops below atmospheric
B. Downstream pressure exceeds supply pressure
C. A vacuum forms in the supply line
D. Water temperature increases
Answer: B
Rationale: Backpressure forces water to flow opposite its intended
direction due to higher downstream pressure.
3. Backsiphonage is caused by:
A. Thermal expansion
B. High downstream pressure
C. Negative pressure in the supply line
, D. Closed valves
Answer: C
Rationale: A vacuum or negative pressure can pull contaminants back into
the potable supply.
4. Which assembly provides the highest level of protection?
A. DCVA
B. PVB
C. SVB
D. RPZ
Answer: D
Rationale: Reduced Pressure Zone assemblies protect against both
backpressure and backsiphonage with high hazard applications.
5. A Double Check Valve Assembly is approved for:
A. High health hazard conditions
B. Low hazard conditions
C. Chemical systems
D. Sewage systems
Answer: B
Rationale: DCVAs are only approved where contaminants are not a health
hazard.
6. The minimum test cock size on most assemblies is:
A. 1/8 inch
B. 1/4 inch
C. 3/8 inch
D. 1/2 inch
Answer: B
Rationale: Most standards require 1/4-inch test cocks for accurate testing.
7. What device uses an air inlet valve?
A. DCVA
B. RPZ
C. AVB
D. RPDA
Answer: C
, Rationale: Atmospheric Vacuum Breakers rely on an air inlet to prevent
backsiphonage.
8. An AVB must be installed:
A. Below all outlets
B. Horizontally
C. At least 6 inches above the outlet
D. Underground
Answer: C
Rationale: Elevation is required to ensure proper air inlet operation.
9. Which assembly can be continuously pressurized?
A. AVB
B. PVB
C. SVB
D. Hose bib vacuum breaker
Answer: B
Rationale: PVBs are designed for continuous pressure, unlike AVBs.
10.Relief valve discharge on an RPZ indicates:
A. Normal operation
B. A malfunction or pressure differential issue
C. Thermal expansion only
D. Proper installation
Answer: B
Rationale: Relief valve discharge signals failure or abnormal pressure
conditions.
11.The purpose of test cocks is to:
A. Drain the system
B. Vent air
C. Allow pressure testing
D. Regulate flow
Answer: C
Rationale: Test cocks provide access points for pressure measurements
during testing.
