What is the minimum diameter of a pressure gauge needed for a leak test on gas piping?

The minimum diameter of a pressure gauge for conducting a leak test on gas piping is indeed 3 inches. This size ensures that the gauge can accurately display the pressure without the risk of damage due to the pressure fluctuations that can occur during a leak test. A larger gauge diameter typically provides better readability and allows for clearer indication of pressure changes, which is crucial when assessing the integrity of gas piping. Gauges that are smaller may not provide the necessary sensitivity or could become less effective at showing subtle pressure differences that might occur during testing. Additionally, proper gauge size is also a factor in adhering to safety standards within the industry, ensuring that all testing equipment is adequate for the tasks they are designed for.