The answer to this question depends on the premises in question and the legal requirements. In large high-rise buildings, such systems are essential to warn all occupants that a fire or emergency situation exists and the system is used to control evacuation in an orderly way. Large sites with a retained fire brigade may require the system to call the brigade and direct them to the area of risk. The property may have considerable intrinsic value and the insurers either require a fire detection system or may incentivise its use.
The building may be unoccupied for periods where equipment is still powered and the owner wishes to ensure that if anything goes wrong fire fighters are called to the scene in a timely manner.
Fire alarm systems are often used for other purposes as well as fire detection and alarm, such as bomb alert signalling, monitoring systems for high risk equipment or places, emergency call systems and even class change systems
Sometimes fire detection and alarm systems are used to compensate for structural fire protection shortcomings or to give special cover for items of high value. Whatever the reason, an automatic fire detection and alarm system generally provides a network of manual callpoints, fire sensors and alarm warning devices over the area covered. It is, in effect, the eyes and mouth of the building to constantly monitor the building and warn if a fire breaks out, or is suspected. In the same way we do if we see flames or smell burning.
Insurance requirements normally relate to the protection of property – rather than life. The objective is therefore to detect fire as early as possible and instigate measures to put the fire out with the minimum amount of damage
Generally a system designed for property protection will also give protection of life as well but the essential difference is that the requirements for property protection are driven from the insurance company’s desires rather than law
Generally the legal requirement for a fire alarm system relates to the protection of life. Either of those in the building or those in adjacent buildings. The primary objective of life protection is to warn occupants of the risk of fire and get them to a place of safety as quickly as possible