The fire alarms, smoke detectors, sprinklers, exit lights, hoods, portable fire extinguishers, and other such warning and protection systems in commercial buildings. Most recently, halon (nonwater) fire-extinguishing systems became an important component, because of the need to protect sophisticated computer and telecommunications equipment in the event of a fire.Industry leaders are now calling for inclusion of protections,or at least warnings,for chemical and biological contaminants associated with possible terrorist attacks. Sometimes called life safety systems.