Fire Safety Regulations Guide

Fire-detection and Warning Systems

In some simple, open-plan, single-storey buildings and warehouses, a fire may be obvious to everyone as soon as it starts. In these cases, where the number and position of exits and the travel distance to them is adequate, a simple shout of 'fire' or a simple manually operated device, such as a gong, whistle or air horn that can be heard by everybody when operated from any single point within the building, may be all that is needed. Where a simple shout or manually operated device is not adequate, it is likely that an electrical fire warning system will be required.

In more complex premises, particularly those with more than one floor, where an alarm given from any single point is unlikely to be heard throughout the building, an electrical system incorporating sounders and manually operated call points (break glass boxes) is likely to be required. This type of system is likely to be acceptable where all parts of the building are occupied at the same time and it is unlikely that a fire could start without somebody noticing it quickly. However, where there are unoccupied areas, or common corridors and circulation spaces in multi-occupied premises, in which a fire could develop to the extent that escape routes could be affected before the fire is discovered, automatic fire detection may be necessary.

The use of these systems may also be risk dependent, so a small factory or warehouse which handles, manufactures, stores or uses low flash point or highly flammable hazardous substances might also need an automatic fire detection system.

You may need to consider special arrangements for times when people are working alone, are disabled, or when your normal occupancy patterns are different, e.g. when maintenance staff or other contractors are working at the weekend.

In large or complex premises, particularly those accommodating large numbers of people, it is likely that a more sophisticated form of warning and evacuation, possibly phased, should be provided.

False alarms from electrical fire warning systems are a major problem (e.g. malicious activation of manual call points) and result in many unwanted calls to the fire and rescue service every year. To help reduce the number of false alarms, the design and location of activation devices should be reviewed against the way the premises are currently used.

Checklist

Can the existing means of detection ensure a fire is discovered quickly enough for the alarm to be raised in time for all the occupants to escape to a place of total safety?

Are the detectors of the right type and in the appropriate locations?

Can the means of warning be clearly heard and understood by everyone throughout the whole building when initiated from a single point?

Are there provisions for people or locations where the alarm cannot be heard?

If the fire-detection and warning system is electrically powered, does it have a back-up supply?