CPD Sanitary Drainage Systems 2

Question 1

What is the minimum slope required for a 4-inch horizontal sanitary drain pipe per the IPC?

Accepted Answer

1/8 inch per foot

Answer

The IPC requires a minimum slope of 1/8 inch per foot for horizontal drain pipes 4 inches in diameter.

Question 2

Which type of fitting is NOT permitted for use in horizontal-to-horizontal sanitary drain connections?

Accepted Answer

Short-pattern quarter bend (sanitary tee used horizontally)

Answer

A sanitary tee used in a horizontal-to-horizontal configuration causes turbulence and is not permitted; wyes and long sweeps are required.

Question 3

In a building sanitary drainage system, what is the primary purpose of a cleanout?

Accepted Answer

Allow access for drain cleaning

Answer

Cleanouts provide access points in the drainage piping so that obstructions can be removed with drain-cleaning equipment.

Question 4

The developed length rule for horizontal drain pipes states that a cleanout must be provided every:

Accepted Answer

100 feet

Answer

The IPC requires cleanouts at maximum 100-foot intervals along horizontal drain piping.

Question 5

Which of the following correctly describes the term 'wet vent'?

Accepted Answer

A vent pipe that conveys both air and wastewater simultaneously

Answer

A wet vent is a pipe that serves as both a drain for one fixture and a vent for another fixture simultaneously.

(CPD) Certified Plumbing Designer Practice Test