Backflow Prevention Devices – Wilmot Plumbing Newcastle.

 

Backflow prevention devices

Suitability of Backflow prevention devices

This table gives examples of backflow prevention devices suitable for each hazard rating indicates protection against back syphonage and/or back pressure.

Dependant upon prevailing regulations, all backflow prevention devices must be tested upon installation, and at least every 12 months thereafter, with the test results being forwarded onto the water supply Authority.

Testable Cross-connection Protection against

High/medium/lowYes

 

(a) Testable Devices
Backflow Prevention DevicesHazard ratingback-pressure
Registered break tank (RBT)High/medium/lowYes
Registertd air gap (RAG)
Reduced pressure zone device (RPZD)*High/medium/lowYesDouble-check valve assembly (DCV)*Medium/lowYesPressure type vacuum breaker (PVB)*Medium/lowNo* Back flow prevention devices that are provided with test taps for the purpose of testing the operation of the devices.

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(b) Non-testable Devices
Non-testable Cross-connectionProtection against
Backflow Prevention DevicesHazard ratingback-pressure
Vented double-check valve (VDCV)*LowYes
Dual-check valve (Dual CV)*LowYes
Dual-check valve with atmospheric vent(Dual CVA)*LowYes
Break tank (BT)*LowYes
Atmospheric vacuum breaker (AVB)*LowNo
Hose connection vacuum breaker (HCVB)*LowNo
Single Check valveFire services only
*Back flow prevention devices that are not provided with test taps for the purposes of testing the operation of the devices.

 

Backflow prevention devices- details

Backflow prevention devices

Backflow prevention devices

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Pressure type vacuum breaker and dual check valve backflow prevention device.

Pressure type vacuum breaker and dual check valve backflow prevention device.

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Hose connection with vacuum breaker

Hose connection with vacuum breaker

 

Regulations may require additional Devices at the property boundary because of a greater risk of unprotected cross connections. Because this additional protection prevents contaminants from entering the mains it is known as property containment or isolation.

Where only sections of a property is protected, this is known as zone protection and when backflow devices are installed adjacent to a machine or fixture, it is termed as individual protection.

Example of Backflow protection in an office building.

Example of Backflow protection in an office building.

Licensed Plumbers must resolve all backflow and cross connections and as a result consumers should consult their local plumbing contractor.

For expert Plumbing Services in Newcastle and Surrounding areas contact

Wilmot Plumbers Newcastle

0432 428 532