Alberta Boilers Safety Association (ABSA) Practice Test

Ensuring the boiler is purged is a critical step before lighting a gas-fired boiler because this process removes any unburned fuel, air, or flammable gases that may have accumulated in the combustion chamber. Purging helps to prevent dangerous explosions or fire hazards by ensuring that the environment inside the boiler is safe for ignition.

If there were residual fuel or gas present when ignition occurs, it could result in an uncontrolled explosion, jeopardizing both equipment and personnel. Therefore, performing a thorough purge confirms that all hazardous materials are eliminated from the combustion area, creating a stable and safe atmosphere for the ignition process to commence.

Although properly securing manhole covers, preparing fuel valves, and ensuring the steam drum vents are open are also important safety and operational procedures, they are secondary steps that do not directly address the immediate risk of combustion safety, which is the primary concern before starting the boiler.