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

New DWV systems are tested with either a water test (filled to the highest point) or an air test at pressures specified by the applicable plumbing code to verify no leaks.

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

Since 2014, the Safe Drinking Water Act requires all plumbing fittings, fixtures, and solder in contact with potable water to be lead-free (less than 0.25% weighted average lead content).

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

Water service lines must be buried at or below the local frost line depth to prevent freezing; if the frost depth is 36 inches, the pipe must be buried at least 36 inches deep.

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

Potable water is water that is safe for human consumption, cooking, and personal hygiene, and plumbing codes contain extensive provisions to protect it from contamination.

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 draft hood (barometric damper) is required on atmospherically vented gas water heaters to prevent flue gases from backdrafting into the living space.

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Plumbing Plumbing Codes & Safety 2