ABC Backflow Prevention Assembly 2

Question 1

Which backflow prevention assembly is required when the downstream piping may be subject to back-pressure AND the supply may be shut off while the downstream system remains pressurized?

Accepted Answer

Reduced pressure principle assembly

Answer

The reduced pressure principle (RP) assembly is required for high-hazard conditions involving back-pressure scenarios where the downstream system may remain pressurized.

Question 2

What does the term 'backsiphonage' refer to in backflow prevention?

Accepted Answer

Negative pressure in the supply line drawing contaminants back

Answer

Backsiphonage occurs when negative (subatmospheric) pressure in the supply line creates a siphon that pulls contaminants backward into the potable water system.

Question 3

A double check valve assembly (DCVA) is appropriate for which hazard classification?

Accepted Answer

Low hazard only

Answer

The DCVA is approved for low-hazard (non-health) cross-connections where there is no risk of contaminating potable water with toxic or health-threatening substances.

Question 4

During an RP assembly field test, if the #1 check valve shows a differential pressure reading below the minimum acceptable threshold, this indicates:

Accepted Answer

The #1 check valve is fouled or failing

Answer

A #1 check valve differential reading below the minimum threshold (typically 5 psi) indicates the check valve is not holding properly and may be fouled or failing.

Question 5

Which of the following cross-connections would be classified as a HIGH hazard?

Accepted Answer

Chemical injection system connected to a cooling tower

Answer

A chemical injection system connected to a cooling tower presents a high hazard because toxic chemicals or biological contaminants could enter the potable supply.

(ABC) Association of Boards of Certification Practice Test

(ABC) Association of Boards of Certification Practice Test

ABC Backflow Prevention Assembly 2