Plumbing Plumbing Codes & Safety 2

Question 1

What type of test is performed on a new DWV system to verify it is watertight?

Accepted Answer

Water test or air test at specified pressures per code

Answer

Air pressure test at 100 psi

Answer

Dye test only

Answer

Visual inspection only

Question 2

What is the purpose of a lead-free requirement in US plumbing codes?

Accepted Answer

To protect potable water from lead contamination in fittings and solder

Answer

To reduce pipe weight

Answer

To meet recycling standards

Answer

To reduce installation costs

Question 3

What is the minimum burial depth for a residential water service line in a climate with a 36-inch frost depth?

Accepted Answer

At or below the local frost line (36 inches)

Answer

12 inches below grade

Answer

24 inches below grade

Answer

48 inches below grade always

Question 4

What is 'potable water' and why is it important in plumbing codes?

Accepted Answer

Water that is safe for human consumption and meets EPA standards

Answer

Heated water above 120°F

Answer

Water treated with chlorine only

Answer

Recycled greywater

Question 5

What safety device is required on a gas water heater flue to prevent backdrafting?

Accepted Answer

A barometric damper or draft hood

Answer

A pressure relief valve

Answer

An expansion tank

Answer

A sediment trap

Question 6

What is required when a new water heater is installed to protect the building from thermal expansion?

Accepted Answer

An expansion tank on the cold water supply side

Answer

A pressure reducing valve only

Answer

A larger T&P valve

Answer

Additional pipe insulation