MCC-NH Gas Fitters Practice Exam

Which method is recommended for locating a leak during a pressure test?

1. Bubble solution

2. Gas detector

3. Water immersion test

4. Lighter

The correct answer is: Bubble solution

Using a bubble solution is recommended for locating a leak during a pressure test because it visually reveals the presence of gas escaping from a pipe or fitting. When the bubble solution is applied to the suspected leak area, any escaping gas will produce bubbles that clearly indicate the location of the leak. This method is effective, widely used, and simple, making it a suitable choice for both professional gas fitters and DIY enthusiasts. While other methods such as gas detectors or water immersion tests can be used under certain conditions, they may not provide the same immediate visual feedback as a bubble solution. Gas detectors are valuable for identifying the presence of gas in the air; however, they may not pinpoint the exact location of a leak like a bubble solution does. A water immersion test can be effective as well, but it typically requires more time and preparation. The use of a lighter is unsafe and not an acceptable or professional method for detecting gas leaks.