2 Building Safety Technologies
2.3 Fire Protection Systems

For reduction of consequences of fires, passive and active fire protection measures are used in buildings. Passive protection is focused on construction, materials and fire resistance of materials used in buildings. For active fire protection, the following technologies can be used:

Fire consequences are less severe if the fire is detected and reported as early as possible. The principle commonly used is quite simple: the building is divided into separate zones in order to limit the fire to the smallest possible space. These zones are equipped with systems for rapid identification of smoke or fire and its restriction in the area of detection. In the zone where fire is detected, fire suppression systems or smoke exhaust ductwork can be activated.

To avoid false alarms, several types of sensors (light, temperature, smoke, etc.) are installed in each fire zone. Evaluation of a fire breakout is based on signals from sensors in a binary logic circuit function called majority (usually majority 2 of 3). That means that if two of three sensors detect a fire then alarm will be triggered.

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Fig. 2.4: Logical scheme