Drainage, Waste & VentQuestion 3 of 120
Except for traps specifically designed as deep seal traps, what is the required liquid seal depth of a fixture trap?
a.1 in to 2 in
b.1-1/2 in to 3 in
c.2 in to 6 in
d.2 in to 4 in
Explanation
A standard fixture trap must hold a liquid seal of not less than 2 in and not more than 4 in. Seals shallower than 2 in evaporate or siphon away too easily, and a seal deeper than 4 in is classified as a deep seal trap, which is permitted only in specific applications, so the wider or shallower ranges are incorrect.
Law Reference: IPC §1002.4Practice all 120 questions free — no signup required.
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