A Fire sprinkler system is an Active fire protection method, consisting of a water supply system, providing adequate pressure and flow rate to a water distribution piping system, onto which fire sprinklers are connected. Although historically only used in factories and large commercial buildings, systems for homes and small buildings are now available at a cost-effective price. Fire sprinkler systems are extensively used worldwide.

How do Fire Sprinkler Systems Function?

The “Sprinkler” is a heat sensing device. Sprinkler Systems are of various types, temperature ranges and designs. The heat sensing element (of the Sprinkler) is pointed to the floor or to the area most prone to fire. The other end of the Sprinkler is connected to a network of pipes storing water under high pressure. Usually from 7bar to 10bar.

When there is a fire, near a Sprinkler; whose temperature is higher than the temperature rated value of the, heat sensing element in the Sprinkler. The bulb present inside the Sprinkler, or the heat sensing device bursts and water now flows through the Sprinkler Systems under pressure directly on to the fire affected area.

All of this is automated and happens, within 3mins, of the fire being detected. In this way Fire Protection Sprinkler System is an automatic, Fire Detection and Extinguishing System. However, Fire Sprinkler Systems was originally meant for Fire Suppression only.

Active and Automated Protection :

Fire Sprinkler Systems are so designed to, be completely automated. This is their major advantage above all other systems. They do not require human intervention of any kind. The basic concept, is that fire will suppressed, at an infant stage. This will stop it from spreading. This is especially more advantages, if it is a residential project. As the Fire Protection System fights the fire, residents can be evacuated from the building. Hence, the chances of any person getting injured or killed because of fire, are very slim. Sprinkler System for Fire Fighting is a very effective method to suppress fire or the spread of fire.

Types of Sprinkler System

Wet Pipe Systems

By a wide margin, wet pipe sprinkler systems are installed more often than all other types of fire sprinkler systems. They also are the most reliable, because they are simple, with the only operating components being the automatic sprinklers and (commonly, but not always) the automatic alarm check valve. An automatic water supply provides water under pressure to the system piping.

Wet Pipe Antifreeze

Wet systems may be charged with an antifreeze chemical, for use where pipes can't reliably be kept above 40 degrees Fahrenheit.

While such systems were once common in cold areas, after several fires caused by systems running too high a percentage of antifreeze, the regulatory authority in the United States effectively banned new antifreeze installations

Dry Pipe Systems

Dry pipe systems are the second most common sprinkler system type. Dry pipe systems are installed in spaces in which the ambient temperature may be cold enough to freeze the water in a wet pipe system, rendering the system inoperable. Dry pipe systems are most often used in unheated buildings, in parking garages, in outside canopies attached to heated buildings.

Deluge Systems

"Deluge" systems are systems in which all sprinklers connected to the water piping system are open, in that the heat sensing operating element is removed, or specifically designed as such. These systems are used for special hazards where rapid fire spread is a concern, as they provide a simultaneous application of water over the entire hazard. They are sometimes installed in personnel egress paths or building openings to slow travel of fire (e.g. openings in a fire-rated wall).

Pre-Action Systems

Pre-action sprinkler systems are specialized for use in locations where accidental activation is especially undesirable, such as in data centers, museums with rare art works, manuscripts, or books; and data centers, for protection of computer equipment from accidental water discharge.

Pre-action systems are hybrids of wet, dry, and deluge systems, depending on the exact system goal. There are two main sub-types of pre-action systems: single interlock, and double interlock.

Foam Water Sprinkler Systems

A foam water fire sprinkler system is a special application system, discharging a mixture of water and low expansion foam concentrate, resulting in a foam spray from the sprinkler. These systems are usually used with special hazards occupancies associated with high challenge fires, such as flammable liquids, and airport hangars. Operation is as described above, depending on the system type into which the foam is injected.

Water Spray

"Water spray" systems are operationally identical to a deluge system, but the piping and discharge nozzle spray patterns are designed to protect a uniquely configured hazard, usually being three-dimensional components or equipment (i.e. as opposed to a deluge system, which is designed to cover the horizontal floor area of a room). The nozzles used may not be listed fire sprinklers, and are usually selected for a specific spray pattern to conform to the three-dimensional nature of the hazard (e.g. typical spray patterns being oval, fan, full circle, narrow jet). Examples of hazards protected by water spray systems are electrical transformers containing oil for cooling or turbo-generator bearings. Water spray systems can also be used externally on the surfaces of tanks containing flammable liquids or gases (such as hydrogen). Here the water spray is intended to cool the tank and its contents to prevent tank rupture/explosion and fire spread.

Water Mist systems

Water mist systems are used for special applications in which it is decided that creating a heat absorbent vapor is the primary objective. This type of system is typically used where water damage may be a concern, or where water supplies are limited. NFPA 750 defines water mist as a water spray with a droplet size of "less than 1000 microns at the minimum operation pressure of the discharge nozzle." The droplet size can be controlled by the adjusting discharge pressure through a nozzle of a fixed orifice size. By creating a mist, an equal volume of water will create a larger total surface area exposed to the fire. The larger total surface area better facilitates the transfer of heat, thus allowing more water droplets to turn to steam more quickly. A water mist, which absorbs more heat than water per unit time, due to exposed surface area, will more effectively cool the room, thus reducing the temperature of the flame.