Plumis, a London-based tech firm, is taking a decidedly different way to control fires. The sprinklers for its Automist Smartscan system are located in the walls. A single ceiling-mounted device senses when there's excessive heat in the room. This activates the wall unit, causing it to scan the room with its infra-red pyrometer. When it detects the hottest point in the room, it shoots a stream of water mist at that location, continuing to do so until the heat signature lessens to the point that it no longer poses a threat.
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