For which hazards is the yellow/cream extinguisher not suitable?

• A. Water-based fires
• B. Electrical equipment only
• C. Solid metals
• D. Flammable gas, electrical equipment and cooking oils/fats

Answer: (D)

Foam extinguishers (the yellow/cream label) use a water-based agent that blankets the fire and cools the fuel, making them good for ordinary combustibles and many liquids. But they’re not suitable for three hazards because the water content creates problems in those situations. For fires in electrical equipment, the water can conduct electricity, posing a shock risk and potentially worsening the fault, so non-conductive extinguishing media are preferred. In kitchens with cooking oils and fats, foam can cause splattering and spreading of the oil rather than smothering it; wet chemical extinguishers are the specialist choice for those fires. And for flammable gas fires, foam doesn’t reliably stop the gas flame or shut off the fuel supply, so other extinguishing agents and gas-control measures are needed. So the hazards that this extinguisher isn’t suitable for include flammable gas, electrical equipment, and cooking oils/fats.