Water Supply & DistributionQuestion 35 of 120
A potable water supply outlet discharges over a receptor and the effective opening of the outlet is 1 in. What is the minimum required air gap?
a.1 in
b.1-1/2 in
c.3 in
d.2 in
Explanation
The air gap must be at least twice the diameter of the effective opening, so 2 x 1 in = 2 in. The 1 in answer is only the code minimum floor that applies to very small openings, not the calculated value here. The 1-1/2 in choice uses a 1.5 multiplier and 3 in uses a 3x multiplier, neither of which the code uses.
Law Reference: UPC §603.3.1Practice all 120 questions free — no signup required.
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