Four Ways to Apply Foam Fire
- The roll-on method can be used on flammable liquid spills that are not diked or uncontained. This method involves the firefighter on the nozzle (or turret in the ARFF apparatus) directing the foam stream near the edge of the liquid fuel that is on fire. Using a sweeping motion, the firefighter creates a complete foam blanket as the foam rolls over the surface of the fuel fire. This controls and extinguishes the fire.
- The deflection method is used when there is an object in which the firefighter can direct the foam stream deflect off of. The stream is directed at the object, causing a disruption in the stream, which then flows down onto the flammable liquid surface. As the foam flows down or deflects off of the object, it rolls over the surface of flammable liquid to control or extinguish the fire.
- The raindrop method calls for the foam stream to be directed into the air, above the fuel fire. The finished foam from the stream then gently rains down upon the surface of the flammable liquid fire until a complete blanket is formed. It is more effective when the stream is allowed to rain over one location of the fire and moved out as the finished foam blanket is formed. This method is employed when the previous methods mentioned here are not feasible, meaning that the spill is too large or there is not an object from which the stream can be deflected off of.
- Sometimes a flammable liquid pool needs to be redirected from an object to create a safer environment or provide a safe path for firefighters to perform rescue operations. This advanced technique requires the foam stream to effectively push away a pool to a desired location by directing it at and then sweeping across the pool's edge. Only experienced professionals who are skilled in this method should ever attempt this technique because of the high probability of splashing or spreading the fuel fire.
Roll-on Method
Bank-Down or Deflection Method
Rain-down or Raindrop Method
Pool Redirection
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