This is a hardwired emergency telephone system for firefighters and emergency personnel. It allows them to communicate reliably with the control centre in order to manage difficult and dangerous situations including phased evacuations of the public from a building.
Large amounts if steel in modern buildings affect the reception of personal radio sets, it is therefore desirable in large or complex buildings to have a 'fixed communication system'.
BS9999 recommends that permanently fixed fire trlrphone handsets should be provided at strategic points. For sports grounds, no person who has an need of an emergency telephone should have to travel more than 30 metres.