What is the best method for extinguishing a grease fire?

Using a Class K fire extinguisher or covering a grease fire with a metal lid is the most effective method for extinguishing this type of fire. Class K fire extinguishers are specifically designed to tackle fires that involve cooking oils and fats, which are common in kitchen environments. These extinguishers discharge a wet chemical that effectively cools and smothers the flames, preventing them from reigniting.

Covering a grease fire with a metal lid also works because it cuts off the oxygen supply to the fire, which is necessary for combustion to continue. By smothering the fire, you eliminate one of the key elements of the fire triangle—oxygen—thereby resolving the situation safely.

Using water directly on a grease fire is highly dangerous, as it can cause the fire to spread explosively due to the reaction between water and hot oil. Similarly, while baking soda can help extinguish small grease fires in some instances, it may not be effective for larger flames and does not provide the same level of assurance as a Class K extinguisher or proper smothering methods. A Class A fire extinguisher, which is intended for ordinary combustibles like wood and paper, is also ineffective for grease fires and can worsen the situation.