Journeyman Plumbers General Plumbing Regulations Questions and Answers

Question 1

Under which of the following circumstances is a combination waste and vent system typically permitted by most plumbing codes?

Accepted Answer

For floor drains and sinks in specific applications like laboratories where conventional venting is structurally impractical.

Answer

Combination waste and vent systems are specialized systems permitted only where structural conditions prevent the installation of a conventional vent system. They are typically used for fixtures like floor drains and sinks in locations such as laboratories or island sinks, where the oversized horizontal drain pipe also serves as the vent.

Question 2

A journeyman plumber is installing a horizontal run of 2-inch Schedule 40 PVC drainpipe. According to the International Plumbing Code (IPC), what is the MAXIMUM allowable spacing between hangers or supports for this pipe?

Accepted Answer

Every 4 feet

Answer

The IPC Table 308.5 specifies the maximum horizontal support spacing for various piping materials to prevent sagging and maintain the required slope. For all sizes of PVC pipe, the maximum allowable spacing between supports is 4 feet.

Question 3

When performing a water test on a newly installed DWV (Drain, Waste, and Vent) system, what is the minimum required head of water that must be applied to the system and for what duration, according to the IPC?

Accepted Answer

10 feet of head for 15 minutes.

Answer

According to IPC Section 312.2, a water test on a DWV system requires it to be subjected to not less than a 10-foot head of water. This pressure must be held for a minimum of 15 minutes without any evidence of leakage.

Question 4

A plumber is installing a 4-inch horizontal building drain that makes a single 90-degree turn. Which of the following statements about cleanout requirements is correct according to most plumbing codes?

Accepted Answer

A cleanout is required at each change of direction greater than 45 degrees.

Answer

Plumbing codes, such as the IPC Section 708.1.4, mandate the installation of cleanouts to allow access for clearing blockages. For horizontal drainage pipes, a cleanout is explicitly required at each change of direction that is greater than 45 degrees.

Question 5

Which of the following is explicitly PROHIBITED by code for the discharge pipe of a water heater's Temperature and Pressure (T&P) relief valve?

Accepted Answer

Installing any type of shutoff valve or tee fitting in the line.

Answer

The discharge line from a T&P valve is a critical safety feature that must remain unobstructed at all times. Installing any valve, tee, or other potential obstruction is strictly prohibited by plumbing codes (IPC 504.6) as it could prevent the valve from relieving dangerous excess pressure or temperature.

Journeyman Plumbers Exam Practice Test

Journeyman Plumbers Exam Practice Test

Journeyman Plumbers General Plumbing Regulations Questions and Answers