Journeyman Plumbers Exam Drainage, Waste, and Vent Systems 4

Question 1

A circuit vent serves:

Accepted Answer

A battery of fixtures connected to a common horizontal branch drain

Answer

A circuit vent serves a group (battery) of fixtures connected to a horizontal branch drain and provides venting for all fixtures in the group with one vent connection.

Question 2

What is the minimum diameter of a roof vent terminal (vent through roof) under most plumbing codes?

Accepted Answer

2 inches

Answer

The minimum diameter for a vent pipe that terminates through a roof is 2 inches to prevent frost closure in cold climates.

Question 3

When connecting a clothes washer standpipe to the drainage system, the standpipe must extend at least how high above the trap?

Accepted Answer

24 inches

Answer

The IPC requires the clothes washer standpipe to extend at least 18 inches but not more than 42 inches above the trap.

Question 4

An air admittance valve (AAV) is NOT permitted to:

Accepted Answer

Replace the main vent stack that terminates to open air

Answer

An AAV cannot replace the main vent stack because the drainage system must have at least one open vent pipe to atmosphere to equalize positive pressures.

Question 5

What is the correct location for a cleanout on a building drain near the foundation wall?

Accepted Answer

Outside the building, at the point where the drain exits the foundation

Answer

A cleanout is required near the junction where the building drain exits the foundation so the entire building drain can be rodded from that point.

Journeyman Plumbers Exam Practice Test

Journeyman Plumbers Exam Practice Test

Journeyman Plumbers Exam Drainage, Waste, and Vent Systems 4