Fire prevention and control, the prevention, detection, and extinguishment of fires, including such secondary activities as research into the causes of fire, education of the public about fire hazards, and the maintenance and improvement of fire-fighting equipment.
Until after World War I little official attention was given to fire prevention, because most fire departments were concerned only with extinguishing fires. Since then most urban areas have established some form of a fire-prevention unit, the staff of which concentrates on such measures as heightening public awareness; incorporating fire-prevention measures in building design and in the design of machinery and the execution of industrial activity; reducing the potential sources of fire; and outfitting structures with such equipment as extinguishers and sprinkler systems to minimize the effects of fire.
The importance of increasing public understanding of the causes of fire and of learning effective reactions in the event of fire is essential to a successful fire-prevention program. To reduce the impact and possibility of fire, the building codes of most cities include fire safety regulations. Buildings are designed to separate and enclose areas, so that a fire will not spread; to incorporate fire-prevention devices, alarms, and exit signs; to isolate equipment and materials that could cause a fire or explode if exposed to fire; and to install fire-extinguishing equipment at regular intervals throughout a structure. Fire-retardant building materials have also been developed, such as the paints and chemicals used to coat and impregnate combustible materials, such as wood and fabric.
In the United States a study conducted over a 10-year period found that the most frequent type of fire was electrical (23 percent of all fires); other causes of fire included tobacco smoking (18 percent), heat caused by friction in industrial machinery (10 percent), overheated materials (8 percent), hot surfaces in such devices as boilers, stoves, and furnaces (7 percent), burner flames (7 percent), and combustion sparks (5 percent).
To reduce the hazardous effects of fire the most basic mechanism is an alarm system, which warns people to leave a building at once, alerts the fire department, and identifies the location of a fire within a structure. Besides the fire alarms that are triggered by people, there are many automatic devices that can detect the presence of fire. These include heat-sensitive devices, which are activated if a specific temperature is reached; a rate-of-rise detector, which is triggered either by a quick or a gradual escalation of temperature; and smoke detectors, which sense changes caused by the presence of smoke, in the intensity of light, in the refraction of light, or in the ionization of air.