Journeyman Plumbers Gas Piping Systems Questions and Answers

Question 1

A plumber is installing a new natural gas piping system that will operate at a standard pressure of 7 inches water column (approx. 0.25 psi).
According to the International Fuel Gas Code (IFGC), what is the minimum required air pressure test for this new installation?

Accepted Answer

3 psig for a minimum of 10 minutes

Answer

10 psig for a minimum of 5 minutes

Answer

0.5 psig for a minimum of 30 minutes

Answer

1.5 times the operating pressure for 15 minutes

Question 2

A plumber is installing a gas line to a new furnace. To protect the appliance's controls from particulate matter, a sediment trap is required. Based on model fuel gas codes, which of the following describes the correct installation of a sediment trap?

Accepted Answer

Downstream of the appliance shutoff valve and before the flexible appliance connector.

Answer

Upstream of the appliance shutoff valve, as close to the main as possible.

Answer

On the vertical pipe dropping down to the appliance, with gas flow passing straight through the tee.

Answer

Only on appliances located in basements or crawlspaces.

Question 3

When installing Corrugated Stainless Steel Tubing (CSST) for a natural gas system, what specific safety measure is mandated by the manufacturer and fuel gas codes to protect against electrical hazards?

Accepted Answer

Bonding the CSST system directly to the building's electrical service grounding electrode system.

Answer

Wrapping the entire length of tubing in an approved insulating tape.

Answer

Installing a dielectric union at the connection to every appliance.

Answer

Ensuring the CSST is installed with at least 6 inches of separation from all electrical wiring.

Question 4

Which of the following locations is strictly prohibited for the installation of gas piping according to the International Fuel Gas Code?

Accepted Answer

Through a circulating air duct or chimney.

Answer

In an accessible, vented attic space.

Answer

Beneath a concrete slab, when sleeved in an approved conduit.

Answer

In a concealed wall space of a residential home.

Question 5

A plumber is running an underground polyethylene (PE) gas line to an outdoor barbecue grill. According to the IFGC, how must the PE pipe be transitioned for the above-ground connection to the appliance?

Accepted Answer

The PE pipe must transition to an approved metallic pipe using a manufactured anodeless riser before it emerges from the ground.

Answer

PE pipe can be run directly to the appliance if it is painted yellow for visibility.

Answer

A section of copper tubing must be used for the last 18 inches below grade before transitioning above ground.

Answer

The PE pipe can extend up to 6 inches above grade if it is sleeved in schedule 40 PVC.

Question 6

When sizing a low-pressure (less than 2 psi) natural gas piping system using the longest-run method, what are the three primary factors used in the sizing tables found in the IFGC?

Accepted Answer

The longest developed length of pipe, the total connected BTU/hr load, and the pipe size.

Answer

Pipe material, outdoor temperature, and number of fittings.

Answer

The building's elevation, the specific gravity of the gas, and the supply pressure.

Answer

The number of appliances, the pipe wall thickness, and the meter pressure.

A plumber is installing a new natural gas piping system that will operate at a standard pressure of 7 inches water column (approx. 0.25 psi).According to the International Fuel Gas Code (IFGC), what is the minimum required air pressure test for this new installation?

A plumber is installing a new natural gas piping system that will operate at a standard pressure of 7 inches water column (approx. 0.25 psi).
According to the International Fuel Gas Code (IFGC), what is the minimum required air pressure test for this new installation?