By Vincent Dunn

There are three ways you can delay flashover. First, by venting the windows of a burning room, you release the build up of heat in there. This slows down flashover in addition to improving visibility in smoke-filled conditions.

Second, by not venting and instead closing the door to the burning room, you can also delay flashover. By not venting, you starve the fire of oxygen, which slows down the combustion rate, which in turn slows down the build up of heat in the room. This may be done when there is a delay in stretching a hose-line and all persons are out of the burning room.

Third, the discharge of a portable extinguisher can cool the heat down in a burning room temporarily and also delay flashover.

• Vincent Dunn is a retired FDNY Deputy Chief. For more details and tips, go to Vincentdunn.com.