SafetyQuestion 339 of 360
A plumber is protecting the public water supply where a commercial boiler with chemical treatment connects to city water (a high-hazard, health-hazard cross-connection). Which backflow assembly is appropriate?
a.A single check valve
b.A reduced-pressure principle (RP) backflow assembly
c.A simple hose bibb
d.No protection is needed for boilers
Explanation
For high-hazard (health-hazard) cross-connections such as a chemically treated boiler, a reduced-pressure principle assembly is required, because it provides the highest level of mechanical protection against both backpressure and backsiphonage of toxic substances. A single check valve or hose bibb offers far less protection. RP assemblies must be tested at least annually by a certified tester.
Law Reference: California Plumbing Code §603Practice all 360 questions free — no signup required.
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