Fire detection & warning systems
This section provides guidance on fire detection and warning systems
Where an electrical fire-warning system is necessary then a straightforward arrangement typically includes the following;
Manual call points (break-glass call points) next to exits with at least one call point on each floor. Electronic sirens or bells.
A control and indicator panel.
An alternative system of interconnected combined manual call points and sounders may be acceptable. If your building has areas where a fire could develop undetected or where people work alone and might not see a fire, then it may be necessary to upgrade your fire-warning system to incorporate automatic detection or install an automatic fire-detection and warning system.
If, for any reason, your system fails you must still ensure that people in your premises can be warned and escape safely. A temporary arrangement, such as gongs, whistles or air horns, combined with suitable training, may be acceptable for a short period, pending your system repairs.
The fire warning sound levels should be loud enough to alert everyone, taking into account background noise. In areas with high background noise, or where people may be wearing hearing protectors, the audible warning should be supplemented, e.g. with visual alarms.
People with hearing difficulties
Where people have hearing difficulties, particularly those who are profoundly deaf, then simply hearing the fire warning is likely to be a major difficulty. If these persons are never alone while on the premises then this may not be a serious problem, as it would be reasonable for other occupants to let them know that the building should be evacuated. If a person with hearing difficulties is likely to be alone, then consider other means of raising the alarm. Amongst the most popular are visual beacons and vibrating devices or pagers that are linked to the existing fire alarm.
Research has shown that some people and, in particular, members of the public, do not always react quickly to a conventional fire alarm. Voice alarms are therefore becoming increasingly popular and can also incorporate a public address facility. The message or messages sent must be carefully considered. It is therefore essential to ensure that voice-alarm systems are designed and installed by a competent person with specialist knowledge of these systems.
In order to quickly determine where a fire has been detected, you should consider displaying a schematic plan showing fire alarm zones in a multi-zoned system adjacent to the control panel.