When operating a portable fire extinguisher, where should you aim the nozzle?

Aiming the nozzle at the base of the fire is the appropriate technique when using a portable fire extinguisher. This approach is effective because it targets the fuel source that is actively burning, which helps to extinguish the fire more effectively. By focusing on the base, you interrupt the combustion process and remove the heat that is necessary for the fire to continue burning.

Aiming at the top of the flames or at the smoke does not address the root of the fire and could allow the flames to continue spreading. Directing the nozzle into the air above the fire also fails to impact the fire directly, thus not facilitating extinguishment. Proper training and techniques emphasize that to successfully extinguish a fire, it is crucial to attack the flames at their source rather than the visible flames or smoke.