GPT System Inspection & Maintenance 3

Question 1

What is the primary purpose of cathodic protection on underground gas piping?

Accepted Answer

To prevent electrochemical corrosion of the metal pipe

Answer

To increase pipe flow capacity

Answer

To mark the pipe's location for excavation crews

Answer

To reduce operating pressure losses

Question 2

A technician is testing pipe joints with leak detection solution and observes bubbling at a threaded connection. What is the correct immediate response?

Accepted Answer

Depressurize the line, disassemble, apply new thread sealant, and retest

Answer

Tighten the joint while the system is pressurized

Answer

Apply additional sealant over the leaking joint without disassembly

Answer

Reduce system pressure by 10% and monitor

Question 3

Which of the following is NOT an acceptable method for locating underground gas piping before excavation?

Accepted Answer

Probing with a metal rod to feel for the pipe

Answer

Calling 811 (one-call utility notification)

Answer

Using a pipe locator or ground-penetrating radar

Answer

Consulting as-built drawings

Question 4

When inspecting flexible gas connectors on appliances, which condition requires immediate replacement?

Accepted Answer

A connector that shows kinking, crimping, or corrosion

Answer

A connector that is 3 years old

Answer

A connector that is longer than 36 inches

Answer

A connector installed in a cabinet enclosure

Question 5

What is the significance of a 'drip leg' (sediment trap) in a gas piping system, and how should it be maintained?

Accepted Answer

It collects moisture and debris; it should be periodically drained or cleaned

Answer

It increases gas pressure; it should be adjusted quarterly

Answer

It reduces gas velocity; it requires no maintenance

Answer

It acts as a pressure relief; it resets automatically

Question 6

A pressure regulator is found to be 'locking up' (pressure rises and stabilizes above setpoint when no gas is flowing). What does this indicate?

Accepted Answer

A failing or worn regulator seat allowing gas to bypass

Answer

Normal operation under no-flow conditions

Answer

The upstream pressure is too low

Answer

The downstream piping has a blockage

Question 7

Which safety precaution must be taken before entering a confined space that contains gas piping for inspection?

Accepted Answer

Test the atmosphere with a combustible gas detector and ensure adequate ventilation

Answer

Turn off the building's main electrical breaker

Answer

Remove all tools from the space first

Answer

Notify the local fire department 24 hours in advance