Passive fire safety construction components are utilized to resist, retard and isolate flames and the associated smoke and fumes: they don't in them selves extinguish flames for this reason These are classed as 'passive defense'. – For complicated web sites with several structures for example educational facilities or colleges – https://www.thesafetycentre.co.uk/blog/ems-wireless-firecell-systems-from-the-safety-centre/