Water Supply & DistributionQuestion 36 of 120
A supply outlet has an effective opening of 3/8 in. What minimum air gap must be provided above the flood level rim of the receiving vessel?
a.3/4 in
b.1 in
c.1-1/4 in
d.2 in
Explanation
Twice the effective opening is 2 x 0.375 = 0.75 in, but the code sets an absolute minimum air gap of 1 in, so 1 in governs. The 3/4 in answer applies the 2x rule without checking the minimum. The 1-1/4 in and 2 in values are larger than anything the rule produces for a 3/8 in opening.
Law Reference: IPC §608.15.1Practice all 120 questions free — no signup required.
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