GPT System Inspection & Maintenance 2 — Questions and Answers
Question 1: When inspecting a gas piping system for corrosion, which condition requires immediate remediation before the system is returned to service?
- Surface rust on an above-ground steel pipe
- Pitting corrosion that has reduced wall thickness by more than 30% (Correct answer)
- Minor discoloration on a coated pipe exterior
- Light oxidation on a brass valve body
Correct answer: Pitting corrosion that has reduced wall thickness by more than 30%
Pitting corrosion that significantly reduces wall thickness compromises structural integrity and creates a leak or rupture risk.
Question 2: A gas technician notices a pressure gauge reading that fluctuates erratically during a static pressure test. What is the most likely cause?
- The regulator is functioning normally
- There is an active leak somewhere in the system (Correct answer)
- The gauge is calibrated too high
- Ambient temperature is affecting the reading
Correct answer: There is an active leak somewhere in the system
Erratic pressure fluctuations during a static test indicate gas is escaping through a leak rather than holding steady.
Question 3: Which document must a technician review before performing maintenance on a gas system in a commercial building?
- The building's fire alarm test records
- The as-built piping drawings and any prior inspection reports (Correct answer)
- The local fire department contact list
- The tenant occupancy schedule
Correct answer: The as-built piping drawings and any prior inspection reports
As-built drawings show actual pipe routing, sizes, and valve locations, which is critical for safe and accurate maintenance.
Question 4: How often must pressure relief valves on gas appliances be manually tested according to standard maintenance practices?
- Every 5 years
- Every 10 years
- Annually (Correct answer)
- Only when a complaint is filed
Correct answer: Annually
Annual manual testing of pressure relief valves ensures they open at the correct set pressure and have not seized.
Question 5: When using an electronic combustible gas detector during a leak survey, what action must be taken if the detector alarms?
- Record the reading and continue the survey
- Mark the location and immediately notify the gas utility or supervisor (Correct answer)
- Reset the detector and retest once
- Ventilate the area and resume normal operations
Correct answer: Mark the location and immediately notify the gas utility or supervisor
An alarm indicates a potentially dangerous gas concentration; the location must be documented and escalated per safety protocols.
Question 6: What is the purpose of painting or labeling exposed gas piping with a specific color or marker?
- To indicate pipe material grade
- To identify the pipe as a gas line and prevent accidental damage (Correct answer)
- To satisfy aesthetic building code requirements
- To show the direction of gas flow
Correct answer: To identify the pipe as a gas line and prevent accidental damage
Identifying markers and colors help workers recognize gas piping and avoid accidental cutting, drilling, or damage during construction.
Question 7: During a routine inspection, a technician finds a gas valve that is partially open and supposed to be fully closed. What should be done first?
- Leave it as found and note it in the report
- Close the valve and investigate why it was open (Correct answer)
- Open it fully to equalize pressure
- Replace the valve immediately
Correct answer: Close the valve and investigate why it was open
Closing the valve to its correct position and investigating prevents unintended gas flow and identifies whether tampering or failure occurred.
GPT System Inspection & Maintenance 2
When inspecting a gas piping system for corrosion, which condition requires immediate remediation before the system is returned to service?