SafetyQuestion 338 of 360
The most reliable protection against backflow contaminating drinking water is a physical separation. What is an 'air gap' as defined for cross-connection control?
a.A vertical, unobstructed space between a water outlet and the flood-level rim of the receiving fixture
b.A rubber flapper inside the faucet
c.A small hole drilled in the supply pipe
d.A gap in the electrical bonding of the piping
Explanation
Under the California Plumbing Code, an air gap is the vertical unobstructed distance through open air between the lowest point of a water supply outlet and the flood-level rim of the fixture or receptacle it discharges into. Because water cannot flow backward across open air, an air gap is the most positive form of backflow prevention. The gap is typically at least twice the effective outlet diameter.
Law Reference: California Plumbing Code §603Practice all 360 questions free — no signup required.
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