🔍 Key Concepts

• Boiler furnace safety procedures before lighting off • Purpose of purging a boiler furnace • Risks of unburned fuel or combustible gases in a cold furnace

💭 Think About

• Think about what might be present in a cold boiler furnace that could cause an explosion when the burner is first lit. • Which step, if skipped, would make it most dangerous to introduce a flame or fuel into the furnace? • Which option deals with removing any possible accumulated vapors or gases from the furnace before ignition?

✅ Before You Answer

• Identify which choice directly clears the furnace of any combustible mixture before lighting off. • Eliminate any options that would reduce your visibility or trap gases inside the furnace. • Confirm which step is a standard first safety action in boiler light‑off procedures.