Systems & CodeQuestion 33 of 110
A circuit vent serves a battery of floor-mounted fixtures on a horizontal branch. What is the maximum number of fixtures a single circuit vent may serve, and where is the vent taken off?
a.Eight, between the two most upstream fixtures
b.Two, downstream of the last fixture
c.Four, at the last fixture
d.Ten, at the base of the stack
Explanation
A circuit vent may serve up to eight fixtures on a horizontal branch, and the vent is taken off the branch between the two most upstream fixtures. A relief vent is added when the branch also receives discharge from upper floors. Water closets in batteries are a classic circuit-vent application.
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