ESFR: Wet Piping

• Developed in 1990, Early Suppression Fast Response, or ESFR, sprinkler systems were designed to put out fires with high pressure water. The sprinkler heads can sense heat 50 percent faster than other heads and trigger gushing water in an attempt to stop the fire before firefighters can respond. This is a wet piping system, which means water sits in the pipes until use.
  
  ESFR systems are most common in large buildings and warehouses, and in warmer areas where pipes won't freeze.
  
  

Dry Piping System

• Dry piping eliminates the risk of frozen pipes, because the pipes are filled with pressurized air. Water sits in a reservoir until a fire triggers the valve to open.
  
  These systems are more common in the northern United States, where pipes freeze easily in low winter temperatures.
  
  

Foam Water Sprinklers

• These sprinklers hold a mixture of water and foam and create a foam spray when in use. They are most commonly used in situations where regular water spray will not put out the flames, such as electrical or flammable liquid fires. The foam spray will smother these types of fire.
  
  

Water Spray

• Water spray systems are built to control a fire until firefighters arrive on the scene with high pressure hoses. The purpose of these is to spray enough water to keep the fire from spreading to flammable objects, but to reduce the damage from excessive amounts of water. The water is released in droplets to cover a larger area within a home or office.
  
  Some sprinkler heads are placed horizontally, so the water sprays sideways in a half-circle. Some heads are suspended perpendicular to the ceiling, and spray in a full circle of mist, covering a wider area. The mist made by the spray allows the water to capture some of the heat made by the fire, turning it into vapor.
  
  

Deluge

• Deluge sprinklers have open coils that allow heat to determine when the sprinkler should go off, similar to ESFR systems. Water is released from all the sprinkler heads in the system. Deluge systems also include a manual start, where a lever can be pulled, setting off the spray of water. Once open, the valves need to be shut off with pliers at the mainframe, usually located in a basement or utility room. Firefighters often shut down the system after dousing a fire at a home or office.
  
  Most houses and offices have deluge water sprinklers, if they have sprinklers at all. Because of the quick response of the deluge coils, they can stop fires quickly.