How should gas pressure tests be performed on existing systems?

Performing gas pressure tests on existing systems is crucial for ensuring safety and functionality. The correct choice involves utilizing a pressure gauge while ensuring that all appliances are turned off. This approach is necessary because when appliances are off, you can accurately assess the integrity of the gas system without the influence of additional gas flow from those appliances. The pressure gauge allows for precise measurement of the gas pressure, which is essential to identify any potential leaks or deficiencies in the system.

Using pressure in the system—while it might seem necessary—should be done carefully, as increasing pressure beyond standard operating levels can cause stress on the components and may lead to unsafe conditions. An electric meter is not appropriate here, as the context specifically pertains to measuring pressure in gas systems rather than electrical metrics. Visual inspections alone are insufficient for testing gas pressure; while they can identify visible issues, they cannot provide quantitative data necessary for safe operation and compliance with regulations. Therefore, the method of using a pressure gauge while appliances are off represents the best practice for conducting a gas pressure test on existing systems.