Backflow Prevention & Cross-Connection Control Flashcards

How frequently should testable backflow prevention assemblies typically be tested according to most water authority requirements?

Answer: Annually, and after any repair, modification, or relocation

Most water authorities require testable backflow prevention assemblies to be tested at least once per year and after any repair, modification, or relocation to confirm continued proper operation.

What instrument does a certified backflow tester use to field-test assemblies?

Answer: A differential pressure gauge test kit with hoses connected to the assembly's test cocks

Certified testers use a differential pressure gauge field test kit with flexible hoses that attach to the test cocks on the assembly to measure pressure differentials across the check valves and relief valve.

When testing an RPZ assembly, what condition indicates the relief valve is functioning correctly?

Answer: The zone between the check valves is maintained at least 2 psi lower than supply pressure, with the relief valve opening if that differential is lost

A properly functioning RPZ maintains a reduced pressure zone at least 2 psi below supply pressure; the relief valve opens to vent water if the differential pressure cannot be maintained, indicating a check valve failure.

Who is authorized to officially test and certify backflow prevention assemblies?

Answer: A certified backflow prevention assembly tester approved by the local water authority or state agency

Only individuals holding a specific backflow prevention assembly tester certification approved by the local water authority or state regulatory agency are authorized to perform official testing and certification.

What is the correct protocol when a backflow prevention assembly fails a field test?

Answer: Remove the assembly from service, repair or replace it, retest, and certify before returning it to service

A failed assembly must be immediately taken out of service; after repair or replacement it must be retested by a certified tester and receive a passing certification before being returned to service.

In most U.S. jurisdictions, who bears primary legal responsibility for ensuring backflow prevention devices on a private irrigation system are properly installed, tested, and maintained?

Answer: The property owner or their authorized representative

Property owners bear the legal responsibility for cross-connection control on their premises, including installation, testing, and maintenance of backflow prevention devices, though they hire certified testers to perform the work.

Which scenario would require an RPZ assembly rather than a PVB for irrigation backflow protection?

Answer: A commercial irrigation system supplied by a reclaimed or recycled water source

Systems connected to reclaimed or recycled water are classified as high-hazard cross-connections and require an RPZ assembly, the highest-rated mechanical backflow protection, per most regulatory codes.