Drainage, Waste & VentQuestion 86 of 360

Horizontal vent piping must be graded so that it:

a.Runs perfectly level
b.Drains any condensate back to the drainage pipe by gravity
c.Slopes away from the drainage system
d.Is installed only vertically

Explanation

Horizontal vent pipes must maintain a slope back toward the drainage piping so condensate and any moisture drain back by gravity and do not pool inside the vent. A level or reverse-sloped vent allows water to collect and block airflow. Vents are not restricted to vertical runs.

Law Reference: 2022 California Plumbing Code (CPC) §905.0

Practice all 360 questions free — no signup required.

Related questions on this topic

Last reviewed: · editorial process

PrepPass Editorial Team · Verified against California CSLB C-36 Plumbing Trade Examination · How we review
Report