PC Material Selection & Properties 2

Question 1

Which pipe material has the highest resistance to chlorine degradation in potable water systems?

Accepted Answer

Cross-linked polyethylene (PEX)

Answer

PEX has superior resistance to chlorine degradation compared to other plastic piping materials used in potable water systems.

Question 2

What is the primary reason copper Type M pipe is NOT recommended for aggressive water conditions?

Accepted Answer

It has the thinnest wall thickness of the copper types

Answer

Type M copper has the thinnest wall of the three copper types (K, L, M), making it more susceptible to corrosion failure in aggressive water.

Question 3

Which material is MOST appropriate for a buried sewer lateral subject to heavy vehicular traffic loads?

Accepted Answer

Extra-strength vitrified clay pipe

Answer

Extra-strength vitrified clay pipe provides excellent compressive strength and chemical resistance, making it ideal for high-load buried applications.

Question 4

What does the term 'SDR' mean when applied to plastic pipe?

Accepted Answer

Standard Diameter Ratio

Answer

SDR stands for Standard Dimension Ratio, which is the ratio of pipe outside diameter to minimum wall thickness.

Question 5

When connecting a copper water line to a galvanized steel pipe, which fitting must be used to prevent corrosion?

Accepted Answer

A dielectric union

Answer

A dielectric union isolates dissimilar metals electrically to prevent galvanic corrosion at the junction of copper and steel.

(PC) Plumber Certification Practice Test

(PC) Plumber Certification Practice Test

PC Material Selection & Properties 2