Structure fires may be attacked with either “interior” or “exterior” resources, or both. Interior crews, using the “two in, two out” rule, may extend fire hose lines inside the building, find the fire and cool it with water. Exterior crews may direct water into windows and other openings, or against any nearby fuels exposed to the initial fire. Hose streams directed into the interior through exterior wall apertures may conflict and jeopardize interior fire attack crews.
Buildings that are made of flammable materials such as wood are different from building materials such as concrete. Generally, a “fire-resistant” building is designed to limit fire to a small area or floor. Other floors can be safe by preventing smoke inhalation and damage. All buildings suspected or on fire must be evacuated, no of fire rating.
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