PC Plumber Water & Drainage 5

Question 1

What is the purpose of a cleanout installed in a drainage system?

Accepted Answer

To provide access for drain cleaning equipment to clear blockages

Answer

To increase water pressure at fixtures

Answer

To vent the drain system to the atmosphere

Answer

To regulate flow between branch drains

Question 2

What is the minimum clearance required in front of a toilet (water closet) to the facing wall or obstruction under the IPC?

Accepted Answer

21 inches

Answer

12 inches

Answer

18 inches

Answer

30 inches

Question 3

A plumber notices that a kitchen sink drain gurgles when a clothes washer discharges nearby. This most likely indicates:

Accepted Answer

Insufficient venting causing back-siphonage

Answer

The kitchen drain pipe is too large

Answer

The water heater pressure is too high

Answer

A clogged water supply strainer

Question 4

Under the IPC, what is the maximum developed length of a 1.5-inch trap arm (from trap weir to vent)?

Accepted Answer

8 feet

Answer

2.5 feet

Answer

5 feet

Answer

10 feet

Question 5

Which fitting is prohibited from use in a horizontal drainage line under most plumbing codes?

Accepted Answer

Double sanitary tee (double tee-wye)

Answer

Long sweep 90-degree elbow

Answer

45-degree wye

Answer

Combination wye and 1/8 bend

Question 6

What is 'hydraulic load testing' used to verify in a new drainage system?

Accepted Answer

Watertightness and proper flow in the drain, waste, and vent system

Answer

Water pressure at supply fixtures

Answer

Thermal expansion in hot water piping

Answer

Correct slope on horizontal supply lines

Question 7

A floor drain installed in a garage must include which special feature to prevent flammable vapors from entering the building through the drain?

Accepted Answer

A trap primer to maintain the water seal

Answer

A backwater valve

Answer

A sediment bucket

Answer

A check valve on the outlet