Ignition begins a chain of change
A heat source ignites fuel, which may be cooking oil, furniture, wiring insulation, bedding, or another material. Heat rises and warms nearby surfaces. Smoke and hot gases collect overhead and begin moving through openings.
Modern furnishings and open layouts can support rapid fire growth. The U.S. Fire Administration warns that residents may have less than two minutes to escape after a smoke alarm sounds.
The room becomes difficult to survive
Smoke can make familiar hallways impossible to see. Heat is much greater near the ceiling, but conditions near the floor can also become dangerous. Smoke and toxic gases are a major threat before flame reaches every part of the room.
A closed door may slow heat and smoke. Opening a door or breaking a window can add oxygen and change fire behavior, sometimes rapidly. Leave ventilation decisions to firefighters.
Escape is the task
Use the safest planned exit, stay low when smoke is present, close doors behind you when possible, go to the meeting place, and call 911 from outside. Do not go back for belongings. Tell firefighters who or what may remain inside.
Sources and further help
This is general information. Follow instructions from firefighters, medical professionals, utilities, building officials, and your insurer.