Water Supply & DistributionQuestion 26 of 360
An air gap and a reduced pressure principle assembly (RP) are both acceptable for high-hazard protection. What is one key advantage of an air gap over an RP assembly?
a.An air gap works under backpressure while pressurized
b.An air gap is a non-mechanical, physical separation that cannot fail closed or foul like a mechanical assembly
c.An air gap requires annual testing while RP does not
d.An air gap maintains downstream pressure
Explanation
An air gap is a fixed physical separation with no moving parts, so it cannot mechanically fail or foul the way an RP can, which is its key reliability advantage. However, an air gap breaks pressure entirely, so it cannot maintain downstream pressure or function as a pressurized in-line device, and it is the RP, not the air gap, that requires periodic testing.
Law Reference: 2022 California Plumbing Code (CPC) §603.0Practice all 360 questions free — no signup required.
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