Which type of fire extinguisher is recommended for putting out fires involving flammable liquids such as grease or gasoline?

The recommended type of fire extinguisher for putting out fires involving flammable liquids such as grease or gasoline is Type B extinguishers. Type B extinguishers are specifically designed to combat fires caused by flammable liquids, which include petroleum-based products, paints, and solvents. This is due to the extinguishing agents in Type B extinguishers, such as foam, dry chemical, or carbon dioxide, which are effective in smothering the flames and inhibiting the chemical reactions that sustain the fire.

In contrast, Type A extinguishers are suitable for ordinary combustibles such as wood, paper, and cloth, but they are not effective on flammable liquids. Type C extinguishers are intended for electrical fires and would not be appropriate for flammable liquids, as introducing water or some other agents used in Type A extinguishers could pose further risks. Type D extinguishers are meant for metal fires, often involving reactive metals, which is a different category of hazards.

Thus, for flammable liquids, the characteristics and effectiveness of Type B extinguishers make them the appropriate choice for handling such dangerous fire situations.