Master Plumber Exam Gas Piping Systems 5

Question 1

A gas-fired water heater installed in a garage must be elevated so the ignition source is at least how high above the floor?

Accepted Answer

18 inches

Answer

Appliances with open flames or ignition sources in garages must be elevated at least 18 inches above the floor to keep ignition above the level where heavier combustible vapors accumulate.

Question 2

When two or more gas appliances are served by a common vent, the vent must be sized based on:

Accepted Answer

The combined total BTU input of all connected appliances

Answer

Common vents must be sized for the total combined BTU input of all appliances connected to ensure adequate draft and safe flue gas removal.

Question 3

What is the purpose of an excess flow valve (EFV) on a gas service line?

Accepted Answer

To automatically shut off gas flow if the pipe is severed or flow exceeds a set threshold

Answer

An excess flow valve automatically closes when gas flow exceeds a preset rate, such as when a service pipe is accidentally broken.

Question 4

Under IFGC, flexible gas connectors are prohibited from passing through:

Accepted Answer

Floors or walls

Answer

Flexible gas connectors must not be concealed within or pass through floors, walls, ceilings, or partitions.

Question 5

A plumber discovers an existing uncoated steel gas pipe buried in soil. The correct action is to:

Accepted Answer

Replace or coat it with approved corrosion protection

Answer

Underground steel gas piping must be protected from corrosion with approved coatings or cathodic protection; uncoated pipe must be corrected.

Master Plumber Exam Practice Test

Master Plumber Exam Practice Test

Master Plumber Exam Gas Piping Systems 5