What is the first step when performing maintenance on a propane system?

• A. Shut off the gas supply, close the cylinder valve, depressurize the line, and verify no gas remains before work.
• B. Ignite a small flame to test system.
• C. Open the cylinder valve wider.
• D. Remove the regulator and proceed.

Answer: (A)

Isolating and depressurizing the propane system before you touch anything is the essential safety step. By shutting off the gas supply and closing the cylinder valve, you stop any new gas from entering the system and isolate the fuel source. Depressurizing the line releases the remaining pressure so you’re not working with pressurized gas in the lines or components. Verifying that no gas remains confirms it’s safe to proceed with maintenance. Introducing an ignition source, like lighting a flame, would create an immediate fire hazard. Opening the cylinder valve wider or removing the regulator while gas is present can release gas unpredictably and increase the risk of fire or explosion.