Journeyman Plumbers Exam Gas Piping Systems 5

Question 1

A gas pipe run exposed in a garage must be protected from vehicle damage by:

Accepted Answer

Routing it at least 6 feet above the floor or installing mechanical protection

Answer

Gas piping in garages must either be installed at least 6 feet above the floor or protected by physical barriers to prevent damage from vehicles.

Question 2

What is the flammability range (lower explosive limit to upper explosive limit) of natural gas in air?

Accepted Answer

5% to 15%

Answer

Natural gas is flammable when its concentration in air is between approximately 5% (LEL) and 15% (UEL); outside this range it will not ignite.

Question 3

When installing a propane (LP) system, the tank must be located a minimum of how far from any building opening?

Accepted Answer

10 feet

Answer

NFPA 58 requires LP-gas containers to be located at least 10 feet from any building opening such as windows, doors, or dryer vents.

Question 4

When using the pressure drop method to size gas piping, what two factors are primarily used in the calculation?

Accepted Answer

Flow rate (CFH) and pipe length

Answer

The pressure drop sizing method uses the calculated flow rate in cubic feet per hour (CFH) and the actual pipe run length to select the appropriate pipe diameter from sizing tables.

Question 5

A gas line passing through a concrete slab must be:

Accepted Answer

Sleeved in a conduit that extends beyond the slab on both sides

Answer

Gas piping penetrating a concrete slab must be installed in a protective sleeve that extends beyond the slab on both sides to prevent corrosion and allow for movement.

Journeyman Plumbers Exam Practice Test

Journeyman Plumbers Exam Practice Test

Journeyman Plumbers Exam Gas Piping Systems 5