What is a common method to extinguish Class B fires?

Class B fires involve flammable liquids such as gasoline, oil, and grease. When it comes to extinguishing these types of fires, it is crucial to use an agent that can effectively displace oxygen or interrupt the chemical reaction occurring in the fire without spreading it.

Using carbon dioxide (CO2) is a common and effective method for extinguishing Class B fires. CO2 is a non-flammable gas that can displace oxygen in the area around the fire, effectively suffocating the flames. Additionally, CO2 extinguishers leave no residue, which is advantageous in many situations where clean-up is a concern, such as when dealing with flammable liquids.

In contrast, water is not suitable for Class B fires as it can cause the flammable liquid to spread or even vaporize, potentially increasing the size of the fire. Steam could also propagate the flames for the same reasons. While dry chemical extinguishers can be effective, specifically designed for Class B fires, in this context, CO2 is one of the most common agents utilized for safely and effectively extinguishing these types of fires.