Which type of extinguisher is best for liquid fires?

The foam extinguisher is best suited for liquid fires due to its ability to form a blanket over the burning liquid. This blanket cools the fire and prevents the release of flammable vapors, effectively smothering the fire and cutting off the oxygen supply. Foam extinguishers are particularly effective on flammable liquids like petrol, oils, and solvents, making them an excellent choice in environments where such materials may be present.

In contrast, while water extinguishers can be effective for solid combustibles, they are not suitable for liquid fires due to the risk of spreading the fire by causing the flammable liquid to float and disperse. Dry powder extinguishers are versatile and can be used on a variety of fires, yet they do not provide the same smothering effect specifically for liquid fires as a foam extinguisher does. CO2 extinguishers are effective for electrical fires and some flammable liquids, but they may not provide adequate cooling and can sometimes lead to re-ignition. Thus, the foam extinguisher stands out as the most effective option for tackling liquid fires.