Backflow Prevention: Essential Knowledge for Plumbing Professionals

Question 1

What is the primary purpose of a backflow prevention device in a plumbing system?

Accepted Answer

Prevent contamination of the potable water supply

Answer

Increase water pressure

Answer

Prevent freezing

Answer

Reduce noise

Question 2

Which type of backflow preventer is recommended for installation in areas with a high potential for backflow, such as hospitals and laboratories?

Accepted Answer

Reduced Pressure Zone (RPZ) Backflow Preventer

Answer

Atmospheric Vacuum Breaker (AVB)

Answer

Double Check Valve Assembly (DCVA)

Answer

Hose Bibb Vacuum Breaker (HBVB)

Question 3

What is the primary purpose of the air gap in a backflow prevention device?

Accepted Answer

To prevent contaminated water from flowing back into the potable water supply

Answer

To reduce water pressure in the system

Answer

To prevent the formation of vacuum in the water line

Answer

To provide a vent for gases

Question 4

Regular testing of backflow prevention devices is crucial to ensure their proper operation. How often should these devices be tested?

Accepted Answer

Annually

Answer

Semi-annually

Answer

Quarterly

Answer

As needed

Question 5

Which of the following is NOT a potential consequence of backflow?

Accepted Answer

Improved water quality

Answer

Contamination of the water supply

Answer

Increased water pressure

Answer

Scalding

Question 6

What is the primary function of a double check valve assembly (DCVA)?

Accepted Answer

To prevent backflow due to cross-connection

Answer

To prevent backflow due to vacuum

Answer

To regulate water flow

Answer

To provide a watertight seal

Question 7

What is a potential risk of neglecting the upkeep of backflow prevention devices?

Accepted Answer

Contamination of the drinking water supply

Answer

Reduced water pressure

Answer

Higher utility bills

Answer

Corrosion of plumbing fixtures

Question 8

Which backflow prevention device uses atmospheric pressure to stop water from flowing in the wrong direction?

Accepted Answer

Pressure Vacuum Breaker (PVB)

Answer

Double Check Valve Assembly (DCVA)

Answer

Reduced Pressure Zone Assembly (RPZA)

Question 9

What is the primary purpose of a backflow prevention device in plumbing systems?

Accepted Answer

To prevent the contamination of the potable water supply by backflow.

Answer

To prevent water leakage from fixtures.

Answer

To regulate water pressure within the system.

Question 10

Which key component of a reduced pressure zone (RPZ) backflow preventer ensures the separation of potable water from non-potable water?

Accepted Answer

Two independently acting check valves

Answer

Vacuum breaker

Answer

Pressure relief valve

Answer

Atmospheric vent

Question 11

What is a potential consequence of backflow contamination?

Accepted Answer

Waterborne diseases and illnesses

Answer

Increased energy consumption

Answer

Reduced water pressure

Answer

Property damage

Question 12

Which of the following is a common application for backflow preventers in commercial buildings?

Accepted Answer

Protecting the potable water supply from contamination by irrigation systems

Answer

Preventing flooding in basements

Answer

Regulating water flow in high-rise buildings

Question 13

What is the primary purpose of a double check valve assembly?

Accepted Answer

To prevent backflow from entering the potable water supply.

Answer

To create a vacuum in the plumbing system.

Answer

To reduce water pressure in a plumbing system.

Question 14

Where should an air gap be installed in a plumbing system?

Accepted Answer

Between the discharge outlet of a fixture and the flood level rim of the receiving fixture.

Answer

At the highest point in the plumbing system.

Answer

Below the water heater.

Question 15

What is the fundamental difference between a backflow preventer and a backflow protection device?

Accepted Answer

Backflow preventers are mechanical devices that physically prevent backflow, while backflow protection devices encompass strategies and measures to safeguard against backflow.

Answer

There is no difference between backflow preventers and backflow protection devices.

Question 16

Which of the following is a common factor contributing to reduced effectiveness in backflow prevention devices?

Accepted Answer

Corrosion and scale buildup

Answer

Regular maintenance

Answer

High water pressure

Answer

Proper installation

Question 17

What is the primary purpose of a test cock in a backflow prevention device?

Accepted Answer

To allow for testing of the device's functionality without shutting off the water supply.

Answer

To drain the device for maintenance.

Answer

To adjust the pressure setting of the device.

Question 18

What should be the initial step when troubleshooting a malfunctioning backflow prevention device?

Accepted Answer

Check the test cocks to verify proper operation.

Answer

Adjust the water pressure.

Answer

Call a licensed plumber.

Answer

Replace the backflow prevention device.

Question 19

Which of the following is a significant health hazard associated with backflow?

Accepted Answer

Contamination of drinking water with sewage

Answer

Reduced water flow

Answer

Increased water pressure

Answer

Damage to plumbing fixtures

Question 20

What is the primary function of a backflow prevention device?

Accepted Answer

To prevent contaminated water from entering the clean water supply.

Answer

To filter impurities from the water.

Answer

To regulate water pressure in the plumbing system.

Question 21

Where should a backflow prevention device be installed?

Accepted Answer

On the supply side of any potential cross-connection.

Answer

On the discharge side of any potential cross-connection.

Answer

Between the water meter and the main shut-off valve.

Question 22

What is the purpose of a test port on a backflow prevention device?

Accepted Answer

To allow for regular testing and maintenance of the device.

Answer

To regulate water pressure in the device.

Answer

To drain excess water from the device.

Question 23

Which of these is a potential consequence of a backflow incident?

Accepted Answer

Contamination of the drinking water supply.

Answer

Reduced water flow rate.

Answer

Increased water pressure in the system.

Answer

Corrosion of pipes.

Question 24

A homeowner uses a garden hose to water their lawn. Which backflow prevention device is most likely needed?

Accepted Answer

Atmospheric Vacuum Breaker (AVB).

Answer

Double Check Valve (DCV) device.

Answer

Reduced Pressure Principle (RPP) device.

Answer

Pressure Vacuum Breaker (PVB).

Question 25

How often should backflow prevention devices be tested and inspected at minimum?

Accepted Answer

Annually.

Answer

Only when a backflow incident is suspected.

Answer

Every two years.

Answer

Every five years.

Question 26

Which of the following is a possible indicator that a backflow prevention device might be malfunctioning?

Accepted Answer

Water leaking from the device when it is not in use.

Answer

The device is constructed from durable materials.

Answer

The device is easy to turn on and off.

Question 27

A plumbing system with a fire sprinkler system connected to the clean water supply would require what type of backflow prevention device?

Accepted Answer

Reduced Pressure Principle (RPP) device.

Answer

Atmospheric Vacuum Breaker (AVB).

Answer

Pressure Vacuum Breaker (PVB).

Answer

Double Check Valve (DCV) device.