Fire System Categories

There are many types of fire alarm systems each suited to different building types and applications. A fire alarm system can vary dramatically in both price and complexity, from a single panel with a detector and sounder in a small commercial property to an addressable fire alarm system in a multi-occupancy building. Systems have to protect both buildings and occupants.

The categories of fire alarm systems are :

    L if they are designed to protect life,

    P to protect buildings and

    M if they are manual system

Life Protection Categories

 

M - Manual Only

Manual call points where recommended and alarms throughout the building. No automatic fire detection (Smoke / Heat detectors). This category of system relies on the occupants of the building discovering the fire and acting to warn others by operating the system. Such systems form the basic requirement for places of employment with no sleeping risk

 

L4 - Protection of escape routes only

L4 systems cover escape routes and circulation areas only. Therefore, detectors will be placed in escape routes, although this may not be suitable depending on the risk assessment or if the size and complexity of a building is increased. Detectors might be sited in other areas of the building, but the objective is to protect the escape route.

 

L3 - AFD Protection on escape routes and rooms opening onto escape routes

This category is designed to give early warning to everyone. Detectors should be placed in all escape routes and all rooms that open onto escape routes. Category 3 systems provide more extensive cover than category 4. The objective is to warn the occupants of the building early enough to ensure that all are able to exit the building before escape routes become impassable.

 

L2 - AFD Protection on escape routes and rooms opening onto escape routes AND other areas of high fire risk

A category L2 system designed for the protection of life and which has automatic detectors installed in escape routes, rooms adjoining escape routes and high hazard rooms. In a medium sized premises (sleeping no more than ten residents), a category L2 system is ideal. These fire alarm systems are identical to an L3 system but with additional detection in an area where there is a high chance of ignition, e.g., kitchen) or where the risk to people is particularly increased (e.g., sleeping risk).

L1 AFD Throughout

A category L1 system is designed for the protection of life and which has automatic detectors installed throughout all areas of the building (including roof spaces and voids) with the aim of providing the earliest possible warning. A category L1 system is likely to be appropriate for the majority of residential care premises. In practice, detectors should be placed in nearly all spaces and voids. With category 1 systems, the whole of a building is covered apart from minor exceptions.

 

Property Protection Categories

P1 - Property protection, automatic detection installed throughout the protected building.

The system is installed throughout the building - the objective being to call the fire brigade as early as possible to ensure that any damage caused by fire is minimized. Small low risk areas can be excepted, such as toilets and cupboards less than 1m²

 

P2 - Property protection, automatic detection in designated areas.

Detection should be provided in parts of the building where the risk of ignition is high and/or the contents are particularly valuable. Category P2 systems provide fire detection in specified parts of the building where there is either high risk or where business disruption must be minimised.