Water Supply & DistributionQuestion 50 of 360
What does an air gap physically prevent that a mechanical check-based device relies on internal parts to prevent?
a.Excessive velocity
b.Any backflow, because there is no physical path for water to travel backward across the gap
c.Thermal expansion
d.Pipe corrosion
Explanation
An air gap creates a physical break in the piping so water has no continuous path to flow backward, preventing both back-siphonage and backpressure without moving parts. It does not control velocity, thermal expansion, or corrosion, which are separate concerns.
Law Reference: 2022 California Plumbing Code (CPC) §603.0Practice all 360 questions free — no signup required.
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