InterNACHI Plumbing Systems Inspection 4

Question 1

What is the minimum distance a plumbing vent must extend above a flat roof where the roof is used as a deck or occupied space?

Accepted Answer

7 feet

Answer

When a roof is used as a deck or occupied area, vents must extend at least 7 feet above the roof surface to keep sewer gases away from occupants.

Question 2

Which of the following is a sign of a failing supply stop valve under a sink?

Accepted Answer

Mineral deposits or corrosion around the valve packing nut

Answer

Mineral deposits or corrosion around the packing nut of a stop valve indicate a slow leak or deteriorating stem seal that can worsen over time.

Question 3

A home inspector finds a water heater in a garage installed directly on the concrete floor. The concern with this installation is:

Accepted Answer

The pilot light or burner ignition is too close to potential fuel vapors at floor level

Answer

Gas water heaters must be elevated at least 18 inches in garages to keep ignition sources above the level where heavier-than-air fuel vapors may accumulate.

Question 4

What is the function of a pressure-reducing valve (PRV) in a residential plumbing system?

Accepted Answer

It reduces high municipal water pressure to a safe level for household piping and fixtures

Answer

A PRV reduces high incoming water pressure (typically above 80 psi) to a safe, consistent pressure, protecting pipes, fixtures, and appliances.

Question 5

Which pipe material is identified by its distinctive orange color and is used for gas supply lines?

Accepted Answer

Corrugated stainless steel tubing with orange jacket (CSST)

Answer

CSST (corrugated stainless steel tubing) with an orange jacket is a flexible gas piping product; it must be properly bonded to mitigate lightning strike risks.

(InterNACHI) International Association of Certified Home Inspectors Practice Test

(InterNACHI) International Association of Certified Home Inspectors Practice Test

InterNACHI Plumbing Systems Inspection 4