Drainage, Waste & VentQuestion 79 of 360
The maximum vertical distance between a fixture outlet and the trap weir must not exceed:
a.12 inches
b.18 inches
c.24 inches
d.30 inches
Explanation
The vertical distance from the fixture outlet down to the trap weir (the fixture tailpiece) must not exceed 24 inches. A longer drop increases discharge velocity and can self-siphon the seal. Values of 12 or 18 inches are within the limit but not the maximum, and 30 inches exceeds it.
Law Reference: 2022 California Plumbing Code (CPC) §1002.0Practice all 360 questions free — no signup required.
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