Which extinguisher is most appropriate for electrical fires on board?

• A. Water
• B. Foam
• C. CO2
• D. Dry chemical

Answer: (C)

When fighting an electrical fire on a vessel, you want an extinguisher that won’t conduct electricity and won’t leave residue that could damage live equipment. Carbon dioxide fits this need because it is non-conductive and displaces the air around the fire without leaving a conductive or corrosive residue. Water-based extinguishers would pose a serious electric shock risk and can spread fire via conductive paths; foam behaves similarly and adds moisture that can worsen electrical damage. Dry chemical extinquisher, while versatile, can leave a powder that clogs and potentially damages sensitive electrical components. So, the best choice for electrical fires aboard is a CO2 extinguisher, used with caution in enclosed spaces due to the asphyxiation hazard.