Passive fire protection construction components are utilized to resist, retard and isolate flames as well as the connected smoke and fumes: they don't in them selves extinguish flames for this reason They can be classed as 'passive defense'. FireCell is based on “Hub & Cluster” technologies an EMS patented infrastructure https://www.thesafetycentre.co.uk/blog/ems-wireless-firecell-systems-from-the-safety-centre/