RMGA Gas Appliance Installation and Service

Question 1

What code governs the installation of natural gas appliances and piping inside buildings in most US jurisdictions?

Accepted Answer

NFPA 54 (National Fuel Gas Code) or ANSI Z223.1

Answer

API 1100

Answer

49 CFR Part 192

Answer

ASME B31.8

Question 2

What is the correct minimum clearance required between a gas appliance and combustible materials?

Accepted Answer

As specified on the appliance listing label and installation instructions

Answer

No clearance required for certified appliances

Answer

Always 36 inches regardless of appliance type

Answer

6 inches for all appliances

Question 3

What type of gas connector is required to connect a natural gas appliance to a rigid piping system?

Accepted Answer

An ANSI-listed flexible gas appliance connector designed for the specific appliance type

Answer

Any flexible hose available at hardware stores

Answer

PVC pipe with threaded connections

Answer

Copper tubing with compression fittings

Question 4

What is the purpose of a drip leg (sediment trap) installed in gas piping near an appliance?

Accepted Answer

To collect condensate, dirt, and pipe scale before they reach the appliance control valve

Answer

To reduce gas pressure to the appliance

Answer

To allow for thermal expansion of the gas piping

Answer

To measure gas flow to the individual appliance

Question 5

What is the minimum thread engagement required for a threaded gas piping connection?

Accepted Answer

As specified in NFPA 54 based on pipe size (typically 3 or more full threads)

Answer

1 thread

Answer

3 threads

Answer

10 threads for all sizes

Question 6

What test is performed on completed interior gas piping before appliances are connected and service is restored?

Accepted Answer

A pressure test using air or nitrogen at 1.5 times the operating pressure or per local code requirements

Answer

A hydrostatic test with water at 200 psig

Answer

A visual inspection only

Answer

A combustible gas detector scan at each fitting