NHIE Plumbing 2

Question 1

What is the minimum slope required for a horizontal drain pipe of 3 inches or less in diameter?

Accepted Answer

1/4 inch per foot

Answer

1/8 inch per foot

Answer

1/2 inch per foot

Answer

1 inch per foot

Question 2

Which type of pipe is NOT approved for use as a drain, waste, and vent (DWV) pipe in most US jurisdictions?

Accepted Answer

CPVC

Answer

ABS plastic

Answer

PVC plastic

Answer

Cast iron

Question 3

A home inspector observes a P-trap installed below the floor slab with no access. What is the primary concern?

Accepted Answer

The trap is inaccessible for cleaning and cannot be inspected for leaks

Answer

P-traps must always be chrome-plated

Answer

P-traps are prohibited below slabs

Answer

The water seal will evaporate faster below a slab

Question 4

What does a water hammer arrestor prevent?

Accepted Answer

Pressure surges that cause banging pipes when valves close quickly

Answer

Backflow of contaminated water into supply lines

Answer

Sediment buildup in water heater tanks

Answer

Freezing of supply pipes in cold climates

Question 5

An inspector finds a vent pipe that terminates 6 inches above the roof surface. What should be noted?

Accepted Answer

In cold climates, the termination should be at least 12 inches above the roof to prevent frost closure

Answer

This is acceptable in all climates

Answer

Vent pipes must terminate at least 24 inches above the roof in all cases

Answer

The vent pipe must be capped to prevent odors

Question 6

Which condition would most likely cause a gurgling sound at a fixture when another nearby fixture is draining?

Accepted Answer

An undersized or blocked vent pipe causing siphoning of trap water seals

Answer

Excessive water pressure at the supply line

Answer

A worn faucet washer

Answer

Galvanized pipe corrosion

Question 7

What is the purpose of a backwater valve installed in a drain line?

Accepted Answer

To prevent municipal sewer water from backing up into the home during flooding

Answer

To regulate hot and cold water mixing temperatures

Answer

To increase water pressure to upper floors

Answer

To allow cleanout access for drain snaking