Plumbing

Question 1

What is the minimum required slope for horizontal drainpipes?

Answer 1

¼ inch per foot for pipes ≤ 2 inches, and ⅛ inch per foot for pipes > 2 inches.

Question 2

What is the purpose of a P-trap in a plumbing system?

Answer 2

To prevent sewer gases from entering the home by holding a water seal.

Question 3

How far should a toilet be from side walls or other fixtures?

Answer 3

Minimum 15 inches from the center of the toilet to any side obstruction.

Question 4

What is the minimum water pressure required for a residential home?

Answer 4

40-60 psi, with 80 psi being the maximum before requiring a pressure regulator.

Question 5

What is the purpose of a TPR (temperature-pressure relief) valve on a water heater?

Answer 5

To release excess pressure and prevent the tank from exploding.

Question 6

Side A

Answer 6

Side B

Question 7

Acrylonitrile-butadiene-styrene (ABS)

Answer 7

Pipe used for drains, waste, and venting.

Question 8

Air chambers

Answer 8

Pressure-absorbing devices that eliminate water hammering. Air chambers should be installed as close as possible to valves or faucets and at the end of long runs of pipe.

Question 9

Air gap (water distribution system)

Answer 9

Unobstructed vertical distance through the free atmosphere between the lowest opening from any pipe or faucet supplying water to a tank, a plumbing fixture, or another device and the flood level rim of the receptacle.

Question 10

Air gap (drainage system)

Answer 10

Unobstructed vertical distance through the free atmosphere between the outlet of a water pipe and the flood level rim of the receptacle into which it is discharged.

Question 11

Air lock

Answer 11

Bubble of air that restricts the flow of water in a pipe.

Question 12

Backflow

Answer 12

Flow of water or other liquids, mixtures, or substances into the distribution pipes of potable water supply from any source or sources other than the intended source.

Question 13

Backflow preventer

Answer 13

Device that prevents the reverse flow of water, due to atmospheric or higher pressure, by means of a positive check valve.

Question 14

Back siphonage

Answer 14

Flowing back to used, contaminated, or polluted water from a plumbing fixture or vessel into a potable water supply due to a negative pressure in the pipe.

Question 15

Bibcock or bib

Answer 15

Water faucet connected to a hose. Also referred to as a sill cock or hose bib.

Question 16

Bleeding

Answer 16

1) Process of drawing air from a water pipe; 2) Seeping of resin or gum from lumber