Design & Sizing第 13 / 110 题
A 2 in trap arm connects a fixture trap to its vent. The code limits the fall in a trap arm to no more than one pipe diameter between the trap weir and the vent. What is the maximum allowable fall in this trap arm?
a.2 in
b.1/2 in
c.1 in
d.1-1/2 in
解析
The maximum fall equals one pipe diameter, and for a 2 in arm that is 2 in. If the arm falls more than one diameter, the vent opening drops below the crown weir and the trap can be self-siphoned. This limit is separate from and in addition to the maximum developed-length limit for the arm.
法律依据: UPC §906.1免费刷完整 110 道题库 — 无需注册。
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