Fire alarm systems are designed to detect fires in the early stages of initiation, when there is still time for the safe evacuation of occupants. Early detection also plays an important role in protecting the safety of responders. Early detection can reduce property damage and minimize downtime because control efforts begin when the fire is small. Most alarm systems provide information to the emergency services about the location of the fire, which speeds up the firefighting process.
To be useful, detectors must be paired with alarms. Alarm systems at a minimum notify the occupants of the building and typically transmit a signal to a manned monitoring station on or off the premises. In some cases, alarms can go directly to the fire service, although this is no longer the norm in most places.
As mentioned above, these systems have numerous advantages. The main limitation is that they do nothing to contain or control the fire. Extinguishing systems, such as automatic sprinklers, work to control the fire. They also report that they are operational, allowing them to perform the function of a heat detection-based system when connected to detectors throughout the building. However, they do not work as quickly as a smoke alarm system. For this reason, facilities where instant notification is essential, even if equipped with sprinkler systems, still needs detection and alarm systems.