History

• The first sprinkler system was invented in the late 19th century by Henry Parmelee, who owned and operated a piano store in Connecticut. Put off by high insurance rates, he decided to skip the insurance policy for fire damage and protect his store using a fire suppression system of his own invention. His design featured closed sprinkler heads that were operated by a pull switch. He hired a manufacturing company called Grinnell to produce his sprinkler systems for sale to other businesses. Eventually, Grinnell developed a more effective version of their own, and quickly became world leaders in the industry. They are credited with designing many sprinkler systems, including automatic versions during the 20th century. Today, most developed countries require builders to install automatic sprinkler systems in many commercial and industrial buildings.
  
  

Function

• Automatic sprinkler systems are composed of a fusible metal link. At a certain temperature level, this link melts, which forces a metal plug into the head, creating pressure that forces water out of the nozzle. Other automatic systems are triggered when a fire alarm is pulled. Nearly all sprinkler heads operate individually, so that if a fire breaks out in a small area, only the heads near that area will activate.
  
  

Benefits

• Sprinkler systems provide the obvious benefit of giving people more time to escape in the event of a fire, thus helping to save lives. They also act to contain the fire and keep it from spreading, as well as to put the fire out as quickly as possible to minimize damage to property and physical assets. In addition, automatic sprinklers systems pay for themselves in the form of lower construction costs and insurance premiums. Even in buildings where they are not required to be installed, sprinkler systems are often used as a precaution. This is because most building codes provide extensive construction leeway for sprinkler buildings. The use of sprinklers means fewer means of egress are required, and larger floor areas are permitted, resulting in more useable space.
  
  

Types

• There are several types of automatic sprinkler systems available. The most common and by far the most widely used is a wet system, where the pipes are already full of water, waiting to be activated. Dry systems, where the pipes are empty of water during normal operation, can be used only in unoccupied areas, or those where the temperature is so low that the pipes could freeze. These dry systems make use of a powder that cuts off oxygen to the fire, in lieu of using water. Pre-action systems are used in areas where the accidental release of water could damage assets, such as libraries and museums. Foam sprinklers are used in areas exposed to highly flammable chemicals, such as industrial buildings. Here, foam is released with the water through the sprinkler head, helping to control fires that may be fed by the chemicals used in the building.
  
  

Considerations

• The regulation of sprinkler systems is controlled by the National Fire Protection Association, also called NFPA. This independent agency is responsible for researching and developing standards for fire protection in the U.S. The regulations they create are not necessarily binding, though most major governing bodies in the U.S. rely on NFPA's research and recommendations when enacting fire codes. Nearly every major commercial building is required to have a sprinkler system of some kind, and those that are not required will often choose to install one anyway to take advantage of cost savings and life safety benefits.