Backflow Prevention Flashcards
7 cards from real Journeyman Plumbers Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Backflow Prevention flashcards as text
A double check valve assembly (DCVA) is appropriate for which hazard classification?
Answer: Low-hazard (non-health) connections only
DCVAs are rated for low-hazard (non-health) cross-connections where contamination would be a nuisance but not a health risk, such as lawn irrigation without chemical injection.
Under the International Plumbing Code (IPC), which backflow preventer is required for a medical dental chair water supply?
Answer: Reduced pressure zone assembly
Dental chair water supplies are considered high-hazard due to potential biological contamination, requiring an RPZ assembly.
What is the minimum distance an RPZ assembly's relief port discharge must be from a sanitary drain receptor to prevent a cross-connection?
Answer: The discharge must never connect directly to the drainage system
The RPZ relief port discharge must terminate with an air gap and must never be directly piped into the drainage system to prevent a drainage cross-connection.
Which standard published by ASSE specifically covers reduced pressure zone backflow preventers?
Answer: ASSE 1013
ASSE 1013 is the performance standard for reduced pressure principle backflow preventers used in potable water systems.
A plumber connects a chemical feed pump directly to a potable water line without any backflow protection. This is best described as:
Answer: An illegal cross-connection creating a high-hazard condition
Any direct connection between a chemical feed system and the potable supply without proper backflow protection is an illegal high-hazard cross-connection.
During a backflow assembly test, the first check valve of an RPZ fails to hold. The correct action is to:
Answer: Report the failed test and have the assembly repaired or replaced before returning to service
A failed backflow preventer test requires the assembly to be repaired or replaced by a qualified technician before it is returned to service.
What is the function of the isolation (shut-off) valves that are integral to a testable backflow prevention assembly?
Answer: They allow the assembly to be isolated for testing and maintenance without shutting down the entire system
Integral isolation valves allow technicians to isolate the backflow assembly for annual testing and repairs while minimizing disruption to the rest of the system.