An automatic sprinkler system is intended to detect, control and extinguish a fire, and warn the occupants of occurrence of fire. The installation comprises fire pumps, water storage tanks, control valve sets, sprinkler heads, flow switches, pressure switches, pipe work and valves. The system operates automatically without human intervention.
Each sprinkler head contains a glass bulb or a fusible link. The bulb contains a liquid and a quantity of vapour. The liquid expands under the influence of heat as do the fusible link heads. When the temperature reaches a certain level – typically at 68 Degree Centigrade – it will expand the liquid and break the bulb or fusible link, which in turn releases water directly onto the seat of the fire.
The hot gases from a fire will make the sprinkler operate. A fire creates a narrow plume of hot air and gasses that rise to the ceiling and spread out. These hot gasses activate the sprinkler head at the correct temperature.
The installation is the most common type and a typical sprinkler is shown as below.