Part 1: Architect’s Guide 1 - 47 Their main purpose is to limit the spread of fire, in order to allow people to escape as quickly as possible and to facilitate the prompt intervention of the emergency services. Detection systems Fire detection requires different types of devices that are characterised by the processes they use (static, velocimetric or differential), the phenomena detected (smoke, flames, heat, gas) and the sphere of activity (confined or linear). Table 6.5 Main type of detectors Detectors Function Application domain Ionic Comparison between ambient air and air contained in exposed room Offices, circulation areas Smoke Abatement or diffusion of light through smoke Computing areas or areas prone to smoke Flames Optical system, sensitive to infrared or ultraviolet light) Storage of inflammable liquids or electrogen group Thermal Sensitive to heat Aggressive areas (in combination with other forms of protection) Thermal velocimetric Sensitive to rapid increase in temperature Aggressive areas (installation near sources of normal heat) Autonomous Detection and Release systems (ADR) also exist. After detecting a local phenomenon linked to fire, one or more Activated Safety Devices (ASD) are released; the purpose is to activate the safety equipment: fire door, smoke extractor, etc. Extinguishers and smoke extraction systems Extinguishing systems commonly applied in warehouses create a foam blanket, the effect of which is to reduce oxygen and/or to cool down the premises. Automatic water fire extinguishers (sprinklers) are designed to detect fire by means of thermo-sensitive sprinkler heads. Gas extinguishers using CO2, FM200, Novec or other gases which rely on the principle of CO2 reduction in the area subject to fire. This process is often used in computer offices, white rooms/laboratories or hospital theatres), etc. Outlet ducts are used to evacuate smoke and hot gases in order to allow people to escape and to limit increase in temperature of the premises. These come in various types of openings (single or double doors with intumescent strips), which are placed on the roof or façades and can be released manually with fuses or using an ADR.
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