Fire Sprinkler System, a network of piping filled with water under pressure is installed behind the walls and ceilings, and individual sprinklers are placed along the piping to protect the areas beneath them. Because the water is always in the piping, the fire sprinkler system is always "on call". If fire breaks out, the air temperature above the fire rises and the sprinkler activates when the air temperature gets high enough.
The sprinkler sprays water forcefully over the flames, extinguishing them completely in most cases, or at least controlling the heat and limiting the development of toxic smoke until the fire department arrives. Only the sprinkler(s) nearest the fire activate. Smoke will not activate sprinklers.
Sprinklers are so effective because they react so quickly. They reduce the risk of death or injury from a fire because they dramatically reduce the heat, flames and smoke produced, allowing people the time to evacuate the home. Home fire sprinkler systems release approximately 10-25 gallons of water per minute. Without sprinklers, a fire is likely to grow to dangerous levels by the time the fire department is able to arrive.
Sprinklers are installed by specially trained contractors who follow NFPA codes and standards and other local requirements. The best time to install sprinklers is when you are building a new home or remodeling an existing home. Nationally, installing sprinklers adds between 1 and 1.5% to the total cost of construction. Installing sprinklers during remodeling, known as "retrofitting", generally costs more and the cost depends on the existing structure.