🔍 Key Concepts

• Class B fires (flammable liquids like oil) and how different agents affect surface burning and vapor suppression • How water fog, foam, CO₂, and dry chemical each work and whether they are compatible when used together • Why a solid stream of water can be dangerous on a burning oil surface

💭 Think About

• For each choice, think: will this combination spread the burning oil, or smother/cool it safely? • Which agent is best at forming a blanket over the fuel surface and which agent is best at cooling adjacent structure without disturbing the fuel? • Are there any combinations where one agent would disrupt or blow away the other, making it less effective?

✅ Before You Answer

• Eliminate any option that uses a solid stream of water directly on the oil surface of a large oil fire • Ask yourself which agent must usually be applied gently after cooling/controlling the area, rather than blasted into the fire • Consider whether gaseous agents (like CO₂) or powder agents (dry chemical) are normally recommended for very large open-deck oil fires exposed to wind, versus surface-covering agents like foam