🔍 Key Concepts

• Boiler flareback and what causes it • Order of priority when responding to a fire/explosion hazard in fuel-burning equipment • Difference between removing air vs removing fuel vs removing products of combustion

💭 Think About

• In a sudden flareback, which immediate action most quickly stops the source of the hazard? • Which choice directly affects the energy source of combustion rather than just its side effects (noise, heat, smoke)? • Think about standard emergency shutdown steps for oil-fired boilers: what is usually done first, before purging or changing ventilation?

✅ Before You Answer

• Identify which option directly stops fuel flow to the seat of combustion. • Consider what must be done before it is safe or effective to purge or adjust ventilation. • Eliminate any step that would tend to spread flames or hot gases through the fireroom instead of controlling them.