CCI Plumbing & Mechanical Systems 2

Question 1

What is the minimum slope required for horizontal drainage piping with a 3-inch diameter per the IPC?

Accepted Answer

1/8 inch per foot

Answer

The IPC requires 3-inch horizontal drainage pipes to slope at a minimum of 1/8 inch per foot toward the point of discharge.

Question 2

A pressure-reducing valve (PRV) is required when the water service pressure exceeds which threshold?

Accepted Answer

80 psi

Answer

Per the IPC, a PRV must be installed when the water supply pressure exceeds 80 psi to protect fixtures and piping.

Question 3

Which type of trap is prohibited under most modern plumbing codes?

Accepted Answer

S-trap

Answer

S-traps are prohibited because they can self-siphon, losing the water seal that prevents sewer gases from entering the building.

Question 4

During a hydrostatic pressure test on new water supply piping, what is the minimum test pressure and duration required by the IPC?

Accepted Answer

100 psi for 15 minutes

Answer

The IPC requires new water supply systems to be tested at 100 psi for a minimum of 15 minutes without leaking.

Question 5

What is the primary function of a backflow preventer in a plumbing system?

Accepted Answer

Prevent contaminated water from entering the potable supply

Answer

A backflow preventer stops contaminated or non-potable water from reversing flow and entering the clean water supply due to back-pressure or back-siphonage.

(CCI) Certified Construction Inspector Practice Test

(CCI) Certified Construction Inspector Practice Test

CCI Plumbing & Mechanical Systems 2