The purpose of the sprinkler system is; to provide an early response to a fire, to take the fire under control and to discharge a certain amount of water within a specific time frame which is calculated by taking into consideration the design zone.
Sprinkler system consists of; sprinkler heads, pipes, connection parts, hangers, plumbing control valves, alarm gongs, flow indicators and fire pumps.
The sprinkler system can be fitted an emergency alarm system that gives warning to the individuals that are inside the building upon the activation of the system.
The legal legislation for fire extinguishing systems in Turkey is “Binaların Yangından Korunması Hakkında Yönetmelik” (Fire protection building code). It is stated that in the rooms/sites where sprinkler systems and their installation are mandatory, the design shall be made according to design parameters that are indicated in the TS EN 12845 standard.
Beside the Turkish standards, in the following article which is stated in the code , ”In the event that Turkish standards don’t have conclusive or adequate judgment about certain issues and in subways, marinas, helipads, tunnels, stadiums, airports and in places that have similar fields of usage, design will be based on European standards. In case neither Turkish nor European standards can adequately cover an issue, then internationally recognised standards could be used as well.”, it mentions that if needed European standards or internationally recognised standards can be taken into consideration during the design of sprinkler systems.
We are aware of the fact that NFPA 13 standard is used in projects frequently for system design both nationally and around the globe. It could be derived that the standards popularity is due to its proven safety measures that relies on vast amount of in-depth test data.
The most important step in the design of sprinkler system is to dictate a design density and operational site, or in another word, to determine the necessary design criteria. Before determining the design criteria, first we must specify the hazard class of the related zones.
As it could be seen below, there are some differences in the specifications of the buildings hazard classes.
|Buildings||TS EN 12845||NFPA 13|
|Parking Areas||Ordinary G.2||Ordinary G.1|
|Plumbing Buildings||Ordinary G.3||Ordinary G.1|
|Cinemas & Theatres||Ordinary G.4||Low|
|Shopping Malls||Ordinary G.3||Ordinary G.2|
|Hazard Zones||Regulation/TS EN 12845||NFPA 13|
|Design Density / Operation area||Design Density / Operation Area|
|Ordinary Hazard G.1||5,0||72||6,1||139|
|Ordinary Hazard G.2||5,0||144||8,1||139|
|Ordinary Hazard G.3||5,0||216||-||-|
|Ordinary Hazard G.4||5,0||360||-||-|
|High Hazard Production G.1||7,7||260||12,2||232|
|High Hazard Production G.2||10,0||260||16.3||232|
|High Hazard Production G.3||12,5||260||-||-|
|High Hazard Production G.4||Deluge System is used.||-||-
The steps should be followed during the design are respectively;
- determining the hazard class
- selection of the system type
- assessing the amount of water required
- determining the sprinkler type
- determining the foundations of piping
- performing a hydraulic analysis
- determining the pipe hanger details
- Wet pipe Sprinkler Systems
- Dry pipe Sprinkler systems
- Preaction Sprinkler Systems
- Single interloc
- Double interlock
- Deluge Sprinkler Systems
When determining the sprinkler type; the intended use of the building, weather conditions and other specific conditions related to the building should be taken into consideration as essential factors.
Mistake that are done in Sprinkler Systems
The misspecification of the design criteria, following this the miscalculation of the water requirements, false selection of sprinkler type, not holding enough water in the water reservoir, the misuse of the water designated for the fire protection for other purposes, in case of having diesel fire pumps not holding any or enough fuel in the tank, the faulty installation of the sprinkler heads according to design criteria, not considering the obstacles that could prevent the discharge of waters on floor, not fixing the piping properly, the use of fixing equipment that don’t comply with standards, faulty production during piping (during welding etc.), not testing overall installation(flow tests etc.), Not using the appropriate seismic hanger parts to take precautions against earthquakes, not doing the necessary maintenance or its controls, not putting the control valves in the pump room into correct position (on/off), not periodically checking up and starting the pumps.