GPT Safety & Leak Detection 2

Question 1

When using electronic combustible gas detectors, the sensor tip should be held how far from the surface being tested?

Accepted Answer

1/4 to 1/2 inch from the surface

Answer

Holding the sensor tip 1/4 to 1/2 inch from the surface allows the instrument to sample gas concentrations escaping from joints or fittings without contaminating the sensor.

Question 2

Which condition makes a soap bubble test unreliable for detecting small gas leaks?

Accepted Answer

Wind or air currents near the test area

Answer

Wind or air currents disperse escaping gas before bubbles can form, making soap bubble tests unreliable outdoors or in drafty areas.

Question 3

A technician detects a gas odor inside a building but cannot locate the source. What is the FIRST action?

Accepted Answer

Evacuate all occupants and call 911 from outside

Answer

Life safety takes priority — evacuate all occupants and call emergency services from outside before taking any other action.

Question 4

What does LEL stand for in the context of gas hazard measurement?

Accepted Answer

Lower Explosive Limit

Answer

LEL (Lower Explosive Limit) is the minimum concentration of gas in air at which ignition can occur, typically around 5% for natural gas.

Question 5

During a pressure test, a technician notices a slow but steady pressure drop over 30 minutes with no soap bubble visible. What should the technician do?

Accepted Answer

Use an electronic detector to locate the concealed leak

Answer

A steady pressure drop indicates a real leak that must be located; an electronic detector is appropriate when visual methods fail to find the source.

(GPT) Gas Pipe Technician Certification Practice Test

(GPT) Gas Pipe Technician Certification Practice Test

GPT Safety & Leak Detection 2