The main components of sprinkler systems comprise: sprinkler heads and piping, sprinkler valve set and the sprinkler system water supply.

Sprinkler head
Each sprinkler head consists of the deflector, fusible link or bulb, plug and the sprinkler head frame. If the temperature rises by more than 30°C relative to the ambient temperature, the sprinkler head fusible link or bulb trips thus allowing the water spray to eject the plug. The water spray is dispersed through the deflector of the sprinkler head creating a parabolic water spray.

Sprinkler heads classified according to the type of deflector:
spray, flat spray (flat jet spray nozzle), concealed spray nozzle and sidewall spray nozzle

Sprinkler heads classified according to the direction of mounting:
upright, pendent (ceiling mounted), sidewall and horizontal sidewall

Sprinkler heads classified according to the response time index (RTI factor) to:
standard response (RTI>80) i quick response (RTI<50) standard response (RTI>80) and quick response (RTI<50) Sprinkler heads with the RTI factor higher than 50 and below 80 are called special response and are not classified under the NFPA standard; they are occasionally used in Europe Sprinkler heads classified according to the K factor (quantity of water supplied by the spray nozzle): The K-factor is defined with the following formula:
Q – flow (l/min)
K – factor
p – pressure (bar)

Standard K-factors are the following:
K57, K80, K115, K160, K200, K242, K320, K363.

Sprinkler heads classified according to the activation temperature:
57°C (orange bulb), 68°C (red bulb), 79°C (yellow bulb), 93°C (green bulb), 141°C (blue bulb), 182°C (light purple bulb), 260°C (black bulb).

Apart from the previously mentioned types, there are other types of closely specialised spray nozzles, such as: dry pendent sprinkler head (the head installed in the areas subject to freezing temperatures connected to the deluge sprinkler network), twin sprinkler head (twin head which releases water only when both bulbs are actuated), in-rack sprinkler heads (heads with a fitted deflector for mounting in the shelving) etc.

Sprinkler valve set
The main purpose of the sprinkler valve set is to signalise the activation of the sprinkler system. The main classification of sprinkler valve assemblies is the following:

Sprinkler Wet type station is a valve set with water contained in the top and bottom chamber. Due to pressure imbalance in the top and bottom chambers (develops when the sprinkler head is set off), the plug of the sprinkler valve is elevated thus releasing the water into the alarm gong line. This line houses an alarm gong providing an audible notification of the fire, as well as a pressure switch which transmits the fire alarm signal to the fire alarm control unit.

Sprinkler dry station is a valve set with air contained in the top chamber and water in the bottom chamber. Due to pressure imbalance in the top and bottom chambers (develops when the sprinkler head is set off), the plug of the sprinkler valve is elevated thus releasing the water into the alarm gong line. This line houses an alarm gong providing an audible notification of the fire, as well as a pressure switch which transmits the fire alarm signal to the fire alarm control unit.

Pre-action sprinkler station is a valve set with air contained in the top chamber and water in the bottom chamber. When the fire alarm system is set off and the pressure in the line drops, the electromagnetic valve is activated causing pressure imbalance on the sprinkler pre-action valve, raising the sprinkler valve plug which releases the water into the alarm gong line. This line houses an alarm gong providing an audible notification of the fire, as well as a pressure switch which transmits the fire alarm signal to the fire alarm control unit.

Sprinkler system water supply
Opskrba vodom sprinkler sustava kao i vremena gašenja sprinkler sustava ovisi o vrsti štićenog prostora, tipu štićenog materijala i veličini sprinkler instalacije.

Supply of water to the sprinkler system and the shutdown time of the sprinkler system depend on the type of protected zone, type of protected material and size of the sprinkler arrangement.

The main classification of the water supply is to: exhaustible and inexhaustible water source. These sources of water are pump rooms connected to water storage tanks and reduced capacity tanks, air to water pressure tanks and the water supply line. In the case of larger sprinkler systems and pursuant to the regulations, different types of water sources are combined in order to increase the safety in the delivery of extinguishing water. Water supply to the sprinkler system should cater to the most demanding case of fire in a building by delivering adequate pressure and adequate quantity resulting from hydraulic calculation.