Water Supply & DistributionQuestion 59 of 360
A single check valve is proposed as backflow protection for a high-hazard chemical connection. Why is this not acceptable?
a.A single check is too expensive
b.A single check increases flow too much
c.A single check is not a tested, fail-safe assembly and provides inadequate protection for a health hazard
d.A single check cannot be installed horizontally
Explanation
A single check valve is not a tested, redundant, fail-safe assembly, so it does not provide the reliability required for a health (high) hazard, which needs an RP or air gap. Cost, flow increase, and orientation are not the reasons a single check is disallowed for high hazards.
Law Reference: 2022 California Plumbing Code (CPC) §603.0Practice all 360 questions free — no signup required.
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