Fire Alarm Categories | Faelsafe: Fire Alarms, Extinguishers and Emergency Lighting in Leeds, Bradford and across West Yorkshire
logo
Fire alarm categories

FIRE ALARM CATEGORIES

ALL FIRE ALARM SYSTEMS ARE DESIGNED IN ACCORDANCE WITH THE BRITISH STANDARD (BS5839 part 1 of 2008)


Listed below are the various categories in this standard, and are used as a guide for system designers, fire authorities, building control, and insurance companies.

Fire alarm systems may be installed in buildings to satisfy one or both of two principal objectives, namely; protection of life and protection of property. The objectives may differ in time or place. Other possible objectives exist, such as protection against business interruption and protection of the environment; these are likely to be satisfied by the recommendations in Bs5839 part 1 of 2008, standard for protection of property.

Because of the great variety of applications for systems covered by this Part of BS 5839, systems are divided into a number of different categories, as follows:

CATEGORY M
Manual systems and, therefore, incorporate no automatic fire detectors.

CATEGORY L

Automatic fire detection systems intended for the protection of life.
They are further subdivided into the following categories:

L1:
Systems installed throughout all areas of the building.
L2:

Systems installed only in defined parts of the building.

A Category L2 system should include the coverage necessary to satisfy the recommendations of this standard for a Category L3 system; the objective of a Category L2 system is identical to that of a Category L3 system, with the additional objective of affording early warning of fire in specified areas of high fire hazard level and/or high fire risk.

L3:
Systems designed to give a warning of fire at an early enough stage to enable all occupants, other than possibly those in the room of fire origin, to escape safely, before the escape routes are impassable owing to the presence of fire, smoke or toxic gases.
L4:

Systems installed within those parts of the escape routes comprising circulation areas and spaces, such as corridors and staircases.

The objective of a Category L4 system is to enhance the safety of occupants by providing warning of smoke within principal escape routes.

NOTE: The installation of detectors in additional areas is not precluded, and the system could then still be regarded as a Category L4 system.

L5:

Systems in which the protected area(s) and/or the location of detectors is designed to satisfy a specific fire safety objective (other than that of a Category L1, L2, L3 or L4 system).

NOTE: The protection afforded by a Category L5 system may, or may not, incorporate that provided by a Category L2, L3 or L4 system.
Often the design is based on a fire risk assessment or forms part of a fire engineering solution. Such a system could be as simple as one that incorporates a single automatic fire detector in one room (in which outbreak of fire would create undue risk to occupants, either in the room or elsewhere in the building), but the system could comprise comprehensive detection throughout large areas of a building in which, for example, structural fire resistance is less than that normally specified for buildings of that type.

CATEGORY P

Automatic fire detection systems intended for the protection of property. They are further subdivided into the following categories:

P1:

Systems installed throughout all areas of the building.

The objective of a Category P1 system is to offer the earliest possible warning of fire so as to minimize the time between ignition and the arrival of fire fighters.

P2:

Systems installed only in defined parts of the building.

The objective of a Category P2 system is to provide early warning of fire in areas of high fire hazard level, or areas in which the risk to property or business continuity from fire is high.

NOTE: The defined parts of the building may be as few as one or more rooms, or as extensive as, for example, complete floors of the building.

Don't Fael To Be Safe

FAELSAFE (SMC) Ltd • All rights reserved.
Copyright 2014 • Site by ShazzooDesigns • All rights reserved.