Backflow Prevention EXAM STUDY GUIDE
2026/2027 ACCURATE QUESTIONS WITH
CORRECT DETAILED SOLUTIONS ||
100% GUARANTEED PASS
<NEWEST VERSION>
1. Backflow - ANSWER ✔ The unwanted reversal of the flow of liquids,
gases, or slurries in a piping system.
2. Backflow Preventer - ANSWER ✔ A device installed in a plumbing
system to prevent the reverse flow of contaminated water into the clean
water supply.
3. Cross-Connection - ANSWER ✔ A physical connection between a potable
water supply and a non-potable source, which can lead to backflow.
4. Atmospheric Vacuum Breaker - ANSWER ✔ A device that prevents
backflow by allowing air to enter the system when a negative pressure
occurs.
5. Reduced Pressure Zone Device - ANSWER ✔ A backflow prevention
assembly that maintains a lower pressure in the protected system than in the
supply line, preventing contamination.
6. Backpressure - ANSWER ✔ A condition in which the pressure in a system
exceeds the supply pressure, potentially causing backflow.
7. Back siphonage - ANSWER ✔ A specific type of backflow that occurs
when there is a negative pressure in the supply line, causing the flow of
water to reverse.
8. Check Valve - ANSWER ✔ A valve that allows fluid to flow in one
direction only, preventing backflow.
,9. Water Quality Standards - ANSWER ✔ Regulations that define the
acceptable levels of contaminants in drinking water to prevent health risks
associated with backflow.
10.Testing and Maintenance - ANSWER ✔ Regular procedures performed on
backflow prevention devices to ensure they function correctly and prevent
contamination.
11.Backflow - ANSWER ✔ The unintended reverse flow of liquid, often in
plumbing systems, which can lead to contamination of potable water.
12.Backflow Prevention Device - ANSWER ✔ A mechanical device designed
to prevent the reverse flow of water in a plumbing system, ensuring safe
drinking water.
13.Cross-Connection - ANSWER ✔ A physical connection between a potable
water supply and a non-potable source, which can create a risk for backflow.
14.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 - ANSWER ✔ Service Connection
15.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 - ANSWER ✔ Repaired or Installed
16.A differential pressure gauge reading of 0.2 psid is represented on water
column sight tube 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) - ANSWER ✔ 5.5 in. (14 cm)
17.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 - ANSWER ✔ Aesthetically bad
18.Water discharged through an air gap to an open tank surface has a pressure
of ____?
A. 0 psi absolute
B. 0 psi atmospheric
C. 0 psi gauge
D. Static line pressure
E. Vapor pressure - ANSWER ✔ 0 psi atmospheric
19.Air-gap separations must be ____?
A. Classified
B. Inspected annually
C. Laboratory listed
D. Tested and repaired
E. Tested with a sight tube - ANSWER ✔ Inspected annually
20.When close to two intersecting walls, an air-gap separation is increased from
2 diameters to _____ diameters.
A. 2.5
B. 3
C. 3.5
D. 4
E. 4.5 - ANSWER ✔ 4
21.An air-gap separation is mandatory between the potable supply and a(n)
_____?
A. Bakery dough mixer
B. Isolation assembly
, C. Pressure washer
D. Sanitary sewer
E. Water meter - ANSWER ✔ Sanitary sewer
22.Toxins may enter a water supply pipe air-gap separation through the ____?
A. Atmosphere
B. Control valve
C. Pressure tank
D. Receiving vessel
E. Sanitary sewer - ANSWER ✔ Atmosphere
23.A properly installed barometric loop will prevent _____?
A. Backpressure
B. Backsiphonage
C. Freezing
D. Leakage
E. Surges - ANSWER ✔ Backsiphonage
24.A swing connection is a type of _____?
A. Backflow preventer
B. Cross-connection
C. Detector assembly
D. Gauge component
E. Shut-off valve repair tool - ANSWER ✔ Cross-connection
25.A barometric loop must be installed 35 ft (10.7 m) above the highest ____?
A. Boiler
B. Fixture outlet
C. Gate valve
D. Service connection
E. Water meter - ANSWER ✔ Fixture outlet
26.A spool is used to connect a ____?
A. Copper and ductile iron pipe
B. Copper and PVC pipe
C. Disc retainer and valve guide
D. Potable and non-potable system
E. Test cock - ANSWER ✔ Potable and non-potable system
2026/2027 ACCURATE QUESTIONS WITH
CORRECT DETAILED SOLUTIONS ||
100% GUARANTEED PASS
<NEWEST VERSION>
1. Backflow - ANSWER ✔ The unwanted reversal of the flow of liquids,
gases, or slurries in a piping system.
2. Backflow Preventer - ANSWER ✔ A device installed in a plumbing
system to prevent the reverse flow of contaminated water into the clean
water supply.
3. Cross-Connection - ANSWER ✔ A physical connection between a potable
water supply and a non-potable source, which can lead to backflow.
4. Atmospheric Vacuum Breaker - ANSWER ✔ A device that prevents
backflow by allowing air to enter the system when a negative pressure
occurs.
5. Reduced Pressure Zone Device - ANSWER ✔ A backflow prevention
assembly that maintains a lower pressure in the protected system than in the
supply line, preventing contamination.
6. Backpressure - ANSWER ✔ A condition in which the pressure in a system
exceeds the supply pressure, potentially causing backflow.
7. Back siphonage - ANSWER ✔ A specific type of backflow that occurs
when there is a negative pressure in the supply line, causing the flow of
water to reverse.
8. Check Valve - ANSWER ✔ A valve that allows fluid to flow in one
direction only, preventing backflow.
,9. Water Quality Standards - ANSWER ✔ Regulations that define the
acceptable levels of contaminants in drinking water to prevent health risks
associated with backflow.
10.Testing and Maintenance - ANSWER ✔ Regular procedures performed on
backflow prevention devices to ensure they function correctly and prevent
contamination.
11.Backflow - ANSWER ✔ The unintended reverse flow of liquid, often in
plumbing systems, which can lead to contamination of potable water.
12.Backflow Prevention Device - ANSWER ✔ A mechanical device designed
to prevent the reverse flow of water in a plumbing system, ensuring safe
drinking water.
13.Cross-Connection - ANSWER ✔ A physical connection between a potable
water supply and a non-potable source, which can create a risk for backflow.
14.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 - ANSWER ✔ Service Connection
15.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 - ANSWER ✔ Repaired or Installed
16.A differential pressure gauge reading of 0.2 psid is represented on water
column sight tube 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) - ANSWER ✔ 5.5 in. (14 cm)
17.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 - ANSWER ✔ Aesthetically bad
18.Water discharged through an air gap to an open tank surface has a pressure
of ____?
A. 0 psi absolute
B. 0 psi atmospheric
C. 0 psi gauge
D. Static line pressure
E. Vapor pressure - ANSWER ✔ 0 psi atmospheric
19.Air-gap separations must be ____?
A. Classified
B. Inspected annually
C. Laboratory listed
D. Tested and repaired
E. Tested with a sight tube - ANSWER ✔ Inspected annually
20.When close to two intersecting walls, an air-gap separation is increased from
2 diameters to _____ diameters.
A. 2.5
B. 3
C. 3.5
D. 4
E. 4.5 - ANSWER ✔ 4
21.An air-gap separation is mandatory between the potable supply and a(n)
_____?
A. Bakery dough mixer
B. Isolation assembly
, C. Pressure washer
D. Sanitary sewer
E. Water meter - ANSWER ✔ Sanitary sewer
22.Toxins may enter a water supply pipe air-gap separation through the ____?
A. Atmosphere
B. Control valve
C. Pressure tank
D. Receiving vessel
E. Sanitary sewer - ANSWER ✔ Atmosphere
23.A properly installed barometric loop will prevent _____?
A. Backpressure
B. Backsiphonage
C. Freezing
D. Leakage
E. Surges - ANSWER ✔ Backsiphonage
24.A swing connection is a type of _____?
A. Backflow preventer
B. Cross-connection
C. Detector assembly
D. Gauge component
E. Shut-off valve repair tool - ANSWER ✔ Cross-connection
25.A barometric loop must be installed 35 ft (10.7 m) above the highest ____?
A. Boiler
B. Fixture outlet
C. Gate valve
D. Service connection
E. Water meter - ANSWER ✔ Fixture outlet
26.A spool is used to connect a ____?
A. Copper and ductile iron pipe
B. Copper and PVC pipe
C. Disc retainer and valve guide
D. Potable and non-potable system
E. Test cock - ANSWER ✔ Potable and non-potable system
