Water Supply & DistributionQuestion 4 of 360
A commercial irrigation system injects fertilizer chemicals into the line and operates under continuous pressure with potential backpressure. Which backflow assembly is required for this high-hazard cross-connection?
a.Atmospheric vacuum breaker (AVB)
b.Pressure vacuum breaker (PVB)
c.Dual check valve
d.Reduced pressure principle backflow assembly (RP)
Explanation
Chemical injection creates a high (health) hazard, and continuous pressure with possible backpressure rules out siphon-only devices. An RP assembly (or an air gap) is the required protection. An AVB and PVB protect only against back-siphonage, not backpressure, and a simple dual check is not rated for a health hazard.
Law Reference: 2022 California Plumbing Code (CPC) §603.0Practice all 360 questions free — no signup required.
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