Drainage, Waste, and Vent Systems Flashcards
7 cards from real Journeyman Plumbers Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Drainage, Waste, and Vent Systems flashcards as text
What is the minimum slope required for a 3-inch horizontal drain pipe under the IPC?
Answer: 1/4 inch per foot
The IPC requires a minimum slope of 1/4 inch per foot for horizontal drain pipes 3 inches in diameter.
A wet vent is permitted to serve which type of fixture combination?
Answer: Bathtub and lavatory on the same floor level
A wet vent typically serves a lavatory and bathtub/shower combination where the drain pipe also functions as the vent for the upstream fixture.
What is the primary purpose of a P-trap in a drainage system?
Answer: To maintain a water seal that blocks sewer gases
A P-trap retains a water seal that prevents sewer gases and odors from entering the building through the fixture drain.
Under the IPC, what is the maximum distance a trap can be located from its vent?
Answer: The distance depends on the pipe size and slope
The maximum trap-to-vent distance is determined by the pipe diameter — for example, 3.5 feet for a 1.25-inch pipe and 6 feet for a 2-inch pipe.
Which fitting type is prohibited for use in a horizontal-to-horizontal drain change of direction?
Answer: Sanitary tee used on its side
A sanitary tee used in a horizontal plane (on its side) does not provide proper flow direction and is prohibited for horizontal drainage.
A stack vent is defined as:
Answer: The extension of the soil or waste stack above the highest horizontal drain connection
A stack vent is the vertical extension of the drainage stack above the topmost fixture connection that terminates through the roof.
When sizing a building drain, the total fixture unit load must be compared to which variable?
Answer: The pipe diameter and slope
Building drain sizing tables in the IPC use both the pipe diameter and the installed slope to determine the maximum allowable drainage fixture unit load.