BACKFLOW PREVENTION
COMPREHENSIVE TEST BANK 2026
VERIFIED QUESTIONS AND ANSWERS
●● What are the two causes of backflow? Answer: Backpressure and
backsiphonage.
●● Define backsiphonage. Answer: Backflow caused by negative
pressure (vacuum) in the supply line.
●● Define backpressure. Answer: Backflow caused when downstream
pressure becomes higher than supply pressure.
●● What is a cross-connection? Answer: Any actual/potential connection
between potable water and a nonpotable source that can cause
contamination/pollution.
●● Difference between contamination and pollution? Answer:
Contamination = health hazard; Pollution = nuisance/quality issue.
●● What is a high hazard (health hazard)? Answer: A condition that
could cause illness or death if backflow occurs (chemicals, sewage,
toxins).
, ●● What is a low hazard (non-health hazard)? Answer: Aesthetic/quality
issue (odor, color, taste) but not a health threat.
●● What is the primary goal of a Cross-Connection Control Program?
Answer: Prevent backflow into the public water system.
●● What is an air gap? Answer: Physical vertical separation between
supply outlet and flood level rim.
●● What is the minimum air gap distance? Answer: 2 times the inside
diameter of supply pipe, but never less than 1 inch.
●● Is an air gap the best protection? Answer: Yes — it provides the
highest level of protection.
●● What is an air break? Answer: Separation but not adequate for
backflow protection like an air gap (often used for drainage).
●● What does a check valve do? Answer: Allows flow one way; closes
when flow reverses.
●● What is a Double Check Valve Assembly (DCVA)? Answer: Two
check valves in series with shutoffs and test *****.
COMPREHENSIVE TEST BANK 2026
VERIFIED QUESTIONS AND ANSWERS
●● What are the two causes of backflow? Answer: Backpressure and
backsiphonage.
●● Define backsiphonage. Answer: Backflow caused by negative
pressure (vacuum) in the supply line.
●● Define backpressure. Answer: Backflow caused when downstream
pressure becomes higher than supply pressure.
●● What is a cross-connection? Answer: Any actual/potential connection
between potable water and a nonpotable source that can cause
contamination/pollution.
●● Difference between contamination and pollution? Answer:
Contamination = health hazard; Pollution = nuisance/quality issue.
●● What is a high hazard (health hazard)? Answer: A condition that
could cause illness or death if backflow occurs (chemicals, sewage,
toxins).
, ●● What is a low hazard (non-health hazard)? Answer: Aesthetic/quality
issue (odor, color, taste) but not a health threat.
●● What is the primary goal of a Cross-Connection Control Program?
Answer: Prevent backflow into the public water system.
●● What is an air gap? Answer: Physical vertical separation between
supply outlet and flood level rim.
●● What is the minimum air gap distance? Answer: 2 times the inside
diameter of supply pipe, but never less than 1 inch.
●● Is an air gap the best protection? Answer: Yes — it provides the
highest level of protection.
●● What is an air break? Answer: Separation but not adequate for
backflow protection like an air gap (often used for drainage).
●● What does a check valve do? Answer: Allows flow one way; closes
when flow reverses.
●● What is a Double Check Valve Assembly (DCVA)? Answer: Two
check valves in series with shutoffs and test *****.
