What type of fire extinguisher is best suited for extinguishing an induction fire in a reciprocating engine?

• A. Carbon Dioxide (CO2)
• B. Dry Chemical
• C. Water
• D. Halotron

Answer: (A)

When a fire starts in the engine’s induction system, the flame is in a confined space where you need to rapidly blanket the fire and starve it of oxygen without leaving behind materials that could damage the engine. Carbon dioxide extinguishers do this effectively by displacing the surrounding air and cooling the flame, rapidly smothering the fire in the intake area. They also leave no particulate residue that could contaminate the fuel-air path or lubricants, which is important in a sensitive engine bay. Dry chemical extinguishers, while versatile, can deposit powders that may foul valves, sensors, and passages in the induction system and require more cleanup. Halotron is a clean agent and useful for sensitive equipment, but it’s typically reserved for equipment bays where residue must be minimized and may not be as practical for flushing a flame inside the intake. Water is unsuitable for a fuel-air fire and can spread flammable liquids. So, for an induction fire inside a reciprocating engine, a carbon dioxide extinguisher provides fast, effective knockout of the flame with minimal risk of collateral contamination.