CORRECT ANSWERS (VERIFIED ANSWERS) Q&A
2027 INSTANT DOWNLOAD PDF
1. What is the primary purpose of a gas piping system?
A. To store natural gas
B. To safely convey gas from the supply source to appliances
C. To increase gas pressure
D. To produce combustion air
Correct answer: B. To safely convey gas from the supply source
to appliances.
Rationale: Gas piping is designed to deliver fuel safely and
reliably from the source to gas-burning appliances.
2. Which gas is commonly used as a fuel in residential gas
piping systems?
A. Oxygen
B. Nitrogen
C. Natural gas
D. Carbon dioxide
Correct answer: C. Natural gas.
Rationale: Natural gas is widely distributed through utility
systems for residential and commercial fuel use.
,3. What is the most important consideration when installing
gas piping?
A. Appearance only
B. Safe containment and delivery of fuel gas
C. Maximum pipe length
D. Paint color
Correct answer: B. Safe containment and delivery of fuel gas.
Rationale: Gas piping must prevent leakage and provide safe
fuel delivery under operating conditions.
4. What is the purpose of a gas shutoff valve?
A. Increase gas pressure
B. Stop gas flow
C. Filter combustion air
D. Remove moisture from gas
Correct answer: B. Stop gas flow.
Rationale: A shutoff valve allows the gas supply to an appliance
or section of piping to be isolated.
5. Where is an appliance shutoff valve generally installed?
A. Only at the gas meter
B. In an accessible location near the appliance
,C. Inside the combustion chamber
D. Inside the chimney
Correct answer: B. In an accessible location near the appliance.
Rationale: An accessible shutoff permits the appliance to be
isolated for servicing or emergencies.
6. What is the purpose of a sediment trap in a gas piping
system?
A. Increase pressure
B. Collect debris and condensate before they enter an
appliance
C. Increase gas temperature
D. Supply combustion air
Correct answer: B. Collect debris and condensate before they
enter an appliance.
Rationale: Sediment traps help protect appliance controls and
burners from contaminants.
7. Which material is commonly approved for fuel-gas piping
when permitted by the applicable code?
A. PVC water pipe
B. Copper or steel piping where specifically permitted
C. Garden hose
D. Rubber tubing of any type
, Correct answer: B. Copper or steel piping where specifically
permitted.
Rationale: Fuel-gas piping materials must be specifically
approved for the application and fuel being used.
8. What should never be used as a substitute for an approved
gas connector?
A. Listed appliance connector
B. Approved flexible connector
C. Water hose
D. Listed gas tubing
Correct answer: C. Water hose.
Rationale: Water hoses are not designed or listed for fuel-gas
service and can create dangerous leaks.
9. What is the purpose of pipe sealant on threaded gas piping?
A. Lubricate the appliance burner
B. Seal threaded joints against gas leakage
C. Increase pipe diameter
D. Reduce combustion air
Correct answer: B. Seal threaded joints against gas leakage.
Rationale: Approved sealant helps make threaded joints gas-
tight.