Plumbing Gas Piping Systems 2

Question 1

When sizing a natural gas pipe, which of the following factors is NOT used in the calculation?

Accepted Answer

Color of the pipe material

Answer

Total length of the pipe run

Answer

Total BTU demand of the appliances

Answer

Allowable pressure drop

Question 2

What unit is commonly used to measure low natural gas operating pressure in residential systems?

Accepted Answer

Inches of water column (in. WC)

Answer

Pounds per square inch gauge (PSIG)

Answer

Millibars (mbar)

Answer

Pascals (Pa)

Question 3

Which type of fitting is NOT permitted for concealed gas piping inside a building?

Accepted Answer

Compression fitting

Answer

Welded joint

Answer

Threaded joint with approved pipe sealant

Answer

Brazed fitting (where approved)

Question 4

What material is PROHIBITED for use as interior gas piping inside a residential building?

Accepted Answer

PVC or CPVC plastic pipe

Answer

Schedule 40 black steel pipe

Answer

Corrugated stainless steel tubing (CSST)

Answer

Copper tubing (where permitted by local code)

Question 5

Where must a manual gas shutoff valve be installed for a new gas appliance?

Accepted Answer

Within 6 feet of the appliance in the same room, in an accessible location

Answer

At the gas meter only

Answer

In the main electrical panel room

Answer

Outside the building near the foundation

Question 6

What is the maximum typical low-pressure natural gas system operating pressure for residential appliances?

Accepted Answer

0.5 psi (14 in. WC)

Answer

2 psi

Answer

5 psi

Answer

10 psi

Question 7

What is the minimum required separation between a gas meter and electrical service equipment?

Accepted Answer

3 feet

Answer

No minimum separation required

Answer

5 feet

Answer

10 feet