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Fundamentals of combustion

For the emergence of a fire three conditions must be met:

  • Presence of a combustible substance
  • supply of air
  • Reaching the ignition temperature of the combustible substance

The graphic shows the so-called fire triangle. If one of these three conditions is not met, no fire can occur. The system fights the fire on two sides of the fire triangle.

On the one hand, as with a classic extinguishing system, the temperature is lowered by the application of water. On the other hand, so-called oxygen displacement occurs with water mist. Due to the fine distribution of the mist, it emerges as a gas and floating as an aerosol. Due to the thermals generated by a fire, the fire supplies itself independently with the aerosol (extinguishing agent). When the water particles hit the seat of the fire, they are vaporized, the water particles change their physical state, absorb energy and expand by around 1,600 times their volume. This leads to a local displacement of oxygen at the seat of the fire.

Functional principle

Depending on the prevailing environmental conditions and the corresponding requirements, the fire is detected by suitable alarm systems.

Larger firefighting systems are often divided into several protection areas.

The detectors forward the signal to a fire alarm control panel, which in turn forwards the signal for each protected area to the interface distributor, but also to other locations, such as the fire brigade, if necessary. From there the signal is transmitted to the control center of the system. This then triggers all the necessary processes to start fighting the fire in the requested area.

System structure
1.     Water container6.     Phoenix control
2.     HP pump 7.     Interface distributor
3.     Operating area distributor8.     Central fire alarm system
4.     Conduit grid9.     Fire alarm technology
5.     Water mist nozzles