Fire Fighter technique to protect firefighters during a backdraft.

What you guys see here is a technique to protect firefighters during a backdraft.

Now, what is a backdraft?

A backdraft is basically what happens when you introduce a fire that has been burning for a while to oxygen. While a fire burns, it slowly uses up all oxygen it can reach. When all the oxygen is gone, the fire starts burning really low, and might not seem like a threat anymore.

Now, what happens during a backdraft is that somehow a major source of oxygen becomes available to the fire. This could be a wall breaking down, someone opening a window etc. The fire gets access to oxygen and starts to burn again. This sudden surge of activity almost looks like an explosion, and is a lethal threat to any firefighters inside the building.