Which advantage does dry chemical have over...

🔍 Key Concepts

• Extinguishing agents: how dry chemical vs CO2 actually put out a fire (smothering, cooling, interrupting chemical chain reaction) • Re-flash (re-ignition): which agent leaves something behind that can still protect the fuel after discharge stops? • Clean agent vs residue: think about which one leaves a mess and which one doesn’t

💭 Think About

• Think about what happens after you stop discharging each agent on a flammable liquid or Class B fire. Which one continues to protect the fuel from air? • Ask yourself which agent physically coats or blankets the fuel, and which one simply displaces oxygen while it is present. • Consider whether an agent that leaves residue is more or less likely to be called ‘clean’ in a practical firefighting sense.

✅ Before You Answer

• Before choosing, be clear on which agent (dry chemical or CO2) is actually considered a clean agent. • Verify in your study materials whether dry chemical is or is not compatible with all foam agents (hint: think about mechanical vs chemical foams). • Focus on which agent is better at preventing re-flash by forming a barrier or interrupting the chemical chain reaction on the fuel surface.

Which advantage does dry chemical have over carbon dioxide (CO2) in firefighting?

More protective against re-flash

Compatible with all foam agents

Cleaner

All of the above

🔍 Key Concepts

💭 Think About

✅ Before You Answer