PC Installation Techniques 2

Question 1

When installing a bathtub drain assembly, what is the correct sequence?

Accepted Answer

Install drain flange first, then connect overflow plate

Answer

The drain flange is installed first into the tub opening, then the overflow plate is connected via the drain linkage to allow the assembly to function properly.

Question 2

What is the minimum slope required per foot for a 4-inch horizontal drain pipe under the International Plumbing Code?

Accepted Answer

1/8 inch per foot

Answer

Under the IPC, a 4-inch horizontal drain pipe requires a minimum slope of 1/8 inch per foot (1% grade) to ensure adequate flow.

Question 3

Which fitting is used to transition from cast iron hub-and-spigot pipe to PVC pipe?

Accepted Answer

Fernco flexible coupling

Answer

A Fernco (mission coupling) flexible rubber coupling is the standard fitting used to connect dissimilar pipe materials such as cast iron and PVC.

Question 4

When installing PEX tubing through a fire-rated wall assembly, what is required?

Accepted Answer

An intumescent firestop fitting or wrap

Answer

PEX penetrations through fire-rated assemblies require intumescent firestop fittings or wraps that expand when heated to seal the opening if the plastic melts.

Question 5

What is the purpose of a vacuum breaker installed on a hose bibb?

Accepted Answer

To prevent backflow from the hose into the potable water supply

Answer

A hose bibb vacuum breaker prevents backflow by admitting air into the line if negative pressure occurs, protecting the potable water supply from contamination.

(PC) Plumber Certification Practice Test

(PC) Plumber Certification Practice Test

PC Installation Techniques 2