Which of the following is a characteristic of Class B fires?

• A. They involve flammable solids
• B. They involve flammable liquids and gases
• C. They exclusively involve electrical materials
• D. They always require water to extinguish

Answer: (B)

Class B fires are specifically identified by their involvement with flammable liquids and gases. This classification includes materials such as gasoline, oil, paint, and other substances that can ignite, leading to fires that pose unique challenges compared to other classes, such as Class A, which involves ordinary combustibles like wood and paper.

Understanding the nature of Class B fires is crucial for firefighting efforts, as the methods for extinguishing them differ significantly. For example, water, which is effective for Class A fires, can exacerbate Class B fires by spreading flammable liquids. Instead, extinguishing agents such as foam, dry chemical, or CO2 are more appropriate for Class B fires to effectively cut off the oxygen supply and quell the flames.

Recognizing that Class B fires encompass flammable liquids and gases underscores the importance of selecting the correct firefighting technique and equipment for effective response in these situations.