When using a dry chemical extinguisher, you should aim at the base of the fire and use which motion?

When using a dry chemical extinguisher, you should aim at the base of the fire and use which motion?

• A. Top of Fire; Sweeping
• B. Sides of Fire; Pulsing
• C. Base of Fire; Pulsing
• D. Base of Fire; Sweeping

Answer: (D)

The important idea is that to extinguish a fire with a dry chemical extinguisher you must reach the fuel source and blanket it. Aiming at the base of the fire ensures the agent hits the part of the fire that continues to feed the flames, not just the visible flames. Sweeping the nozzle from side to side across the base spreads the powder over the burning surface, covering it quickly and forming a barrier that interrupts the chemical reactions occurring at the flame and prevents reignition. Aiming at the top or sides won’t effectively cover the fuel, and short, pulsing bursts often miss large areas, leaving unprotected fuel that can flash back. Sweeping across the base is the most reliable method to extinguish with a dry chemical extinguisher.

The important idea is that to extinguish a fire with a dry chemical extinguisher you must reach the fuel source and blanket it. Aiming at the base of the fire ensures the agent hits the part of the fire that continues to feed the flames, not just the visible flames. Sweeping the nozzle from side to side across the base spreads the powder over the burning surface, covering it quickly and forming a barrier that interrupts the chemical reactions occurring at the flame and prevents reignition. Aiming at the top or sides won’t effectively cover the fuel, and short, pulsing bursts often miss large areas, leaving unprotected fuel that can flash back. Sweeping across the base is the most reliable method to extinguish with a dry chemical extinguisher.