Passive fire security design elements are accustomed to resist, retard and isolate flames and also the related smoke and fumes: they do not in them selves extinguish flames hence They are really classed as 'passive security'. Smoke detectors will be the equipment and sensors that can figure out prospective fire https://www.thesafetycentre.co.uk/blog/ems-wireless-firecell-systems-from-the-safety-centre/