🔍 Key Concepts

• How foam, gases, and water-based agents extinguish fire (cooling vs smothering vs vapor suppression) • The idea of a floating or buoyant blanket on top of a flammable liquid • Difference between water fog, steam, CO2, and foam in how they act on burning vapors

💭 Think About

• Ask yourself: which agent can actually float on top of a flammable liquid and form a layer between fuel and air? • Consider which agent creates a stable surface layer rather than just mixing with the air or quickly dispersing. • Think about which one is specifically designed to control flammable liquid fires by covering the surface.

✅ Before You Answer

• Verify which agent is commonly used on flammable liquid (Class B) fires to form a surface seal. • Check which option creates a physical blanket or film on the fuel surface, not just displacement of oxygen. • Confirm which agent is described in your materials as having a buoyant, floating layer that suppresses vapors.