Red Seal Gasfitter — Class B Practice Exam

What is the minimum pressure test duration for new gas lines?

1. 10 minutes

2. 20 minutes

3. 30 minutes

4. 40 minutes

The correct answer is: 30 minutes

When testing new gas lines, the minimum pressure test duration is generally set to ensure the integrity and safety of the installation before it is put into operation. A 30-minute duration is required because it allows sufficient time to detect any potential leaks in the system. This time frame measures if the pressure remains stable, indicating no leaks are present. Longer testing durations provide a more rigorous assessment of the installation’s integrity, but 30 minutes strikes a balance between practicality and thorough inspection. It's important to follow established codes and guidelines, which often specify these minimum durations as part of safety protocols. In the context of other options, shorter durations may not provide enough time to reliably determine if the gas line is leak-free, while longer durations, although suitable, exceed the minimum requirements necessary for a safe assessment.