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Flashcards in Cross Connection Control Deck (23)
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1
Q

Minimum test frequency for back flow prevention assemblies.

A

At least yearly

2
Q

More frequent than annual testing of back flow assemblies may be indicated under these conditions.

A
  • Extremely high hazard condition- History of annual test failure
3
Q

This should be required if a facility has an auxiliary water system that is or could be connected to the public water system.

A

An approved back flow prevention assembly installed at the water service to the facility

4
Q

This method of cross connection control is typically required on the service to a sewage treatment plant.

A

Approved air gap separation

5
Q

Approved cross connection control methods when chemicals or other high hazard materials may enter the potable water system.

A
  • Reduced back flow assembly (RPBA)- Air gap (AG)
6
Q

Air gap.

A

Vertical separation between a potable water supply pipe and the flood rim of a receiving vessel at least 2x the supply pipe diameter, but never less than one inch.

7
Q

Facilities that may have high hazard cross connections.

A
  • Hospital- Mortuary- Chemical plant- Metal plating plant- Sewage treatment plant
8
Q

Contamination.

A

Introduction of materials into water such as disease producing micro-organisms or toxic substances that pose a health risk

9
Q

Pollution.

A

Introduction of materials into water that are objectionable, and will render the water unfit for its intended use

10
Q

Cross connection.

A

Any actual or potential physical connection between a potable water line and any pipe, vessel, or machine containing a non-potable fluid so that it is possible for the non-potable fluid to enter the potable line by backflow

11
Q

Hydraulic conditions that can cause backflow.

A
  • Back pressure- Back siphonage
12
Q

Key installation requirement for reduced pressure backflow assemblies.

A

Insure that relief valve cannot be submerged

13
Q

Hazard compatible with double check valve assembly.

A

Low hazard only

14
Q

Selection of a backflow prevention assembly is based on this.

A
  • Degree of hazard- Hydraulic condition (back pressure or back siphonage)
15
Q

Cross connection control where there are toxic chemicals such as pesticides or fertilizers require this type of protection.

A

RPBA or air gap protection

16
Q

Use of these types of chemicals may pose a backflow contamination threat.

A
  • Pesticides- Fertilizers- Boiler and heat exchanger chemicals- Antifreeze chemicals- Cleaning agents such as soaps and detergents
17
Q

These backflow prevention devices should only be used in a back siphonage condition, never back pressure.

A

Vacum breakers:

  • Atmospheric vacum breaker
  • Pressure vacum breaker
18
Q

This backflow assembly includes a spring loaded air inlet valve and a check valve.

A

Pressure vacuum breaker

19
Q

These backflow prevention methods protect against back pressure, and back siphonage.

A
  • Air gap
  • Reduced pressure backflow assembly
  • Double check valve assembly
20
Q

An improperly operated fire truck pumper can create this distribution system hazard.

A

Back siphonage due to low pressure in the main

21
Q

Implement a cross connection control program.

A
  • Local ordinance that empowers a water supplier to implement a program
  • Water use inspection of facilities supplied by the water system
  • Installation of backflow devices at facilities where the cross connection hazards are identified
  • Backflow assembly testing program, to provide annual test
22
Q

This backflow assembly includes two independently operating check valves and a differential pressure relief valve.

A

Reduced pressure backflow assembly (RPBA)

23
Q

Reasons a relief port must never be plugged or extended.

A
  • It would interfere with the operation of the relief valve.

- It would interfere with the testing of the backflow assembly.