In just 3½ minutes, the heat from a room fire can reach 1100 degrees F. As this happens, flashover occurs. Everything in the room bursts into flames—wood dining table, wood and upholstered chairs, cookbooks, curtains and wall decorations. The oxygen in the room is virtually sucked out (used up during the rapid combustion); glass windows shatter. Balls of fire and flames shoot out windows and doorways. The upstairs fills with thick, hot, noxious smoke and the stairwell is impassible. When you have flashover in a room, temperatures can reach up to 1,400 degrees F—now, all of the other rooms in the house are severely at risk.