If you open an air test fitting and air is escaping, what is that an indication of?

• A. Fire
• B. A leak
• C. Over-pressurization
• D. Blocked line

Answer: (A)

The idea behind an air test is to pressurize a line and listen for air leaking out. If you open the test fitting and air escapes, that shows there’s a leak at that point or somewhere in the connected section—the air is finding a path to the outside rather than staying in the line. The correct action is to locate and fix the leak (tighten fittings, replace damaged parts) and re-test to ensure the system holds pressure. This isn’t an indication of a fire, which would involve heat or flames, not just pressurized air escaping. Over-pressurization would show up as a gauge reading rising or a relief valve activating, not continuous escaping air at the fitting.