Fire detection and alarm systems (BAFE SP203-1)

A fire detection and alarm system must be designed, installed and maintained in line with industry standards (BAFE SP203-1) so that when called on it activates to ensure the safety of people and property.

NSI approved companies are continually assessed by our team of specialist auditors to ensure they remain competent to design, install and commission a system that meets your needs and undertake maintenance to ensure your system will operate effectively should it be activated.

When choosing a fire alarm system there are many factors to be considered such as the activities being undertaken, the individuals within the building, the building structure and all the associated risks.

Fire alarm systems essentially operate on the same principle. If a detector detects smoke or heat or someone operates a break glass unit (manual call point), then alarm sounders operate to warn occupants to evacuate the premises.


Fire Detection and Alarm System categories

Manual systems

Category M. M systems require manual call points to be located on all escape routes and in particular at all exit points. Persons are not expected to walk more than 45m to operate one, although this distance may be significantly reduced where persons of limited mobility are expected to be first to activate the call points or if there is a risk of a fire developing rapidly.

Property protection

Systems designed for protection of property only, fall into one of two categories: P1 or P2.

Category P1. The objective of a P1 system is to provide the earliest possible warning of a fire and is designed to protect the whole building. Where a P1 includes manual call points, this would be categorised as a P1/M.

Category P2. These systems are installed in defined parts of the building, which may have a high fire hazard level or from where there is a significant risk of the fire spreading and causing damage to high value items. Where a P2 includes manual call points, this would be categorised as a P2/M.

Life protection

Life Protection systems are designed on a hierarchical basis from Category L5 to Category L1, where L5 protects specific fire risks within a building and L1 provides full coverage. The category selected will depend on a risk assessment of the activities being undertaken within the building, the individuals using the building and the design of the building.

Categories L1-L5 Fire Alarm Systems

Category L5. L5 fire alarm systems are designed for buildings or areas within a building to fulfil a specific fire safety objective.

Category L4. L4 fire alarm systems provide detection in the circulation areas of a building used as escape routes, such as corridors and stairways.

Category L3. In additional to the requirements of L4, Category L3 fire alarm systems also provide detection in all rooms leading onto the escape route to alert people prior to any escape route becoming ‘smoke logged’.

Category L2. L2 systems cover all the areas identified in a L3 systems with additional protection provided in areas where a high fire hazard level or fire risk is identified.

Category L1. L1 systems provide protection throughout the building to provide the earliest warning of fire to achieve the longest possible time for escape.

Once the category of fire alarm system has been determined  by carrying out a fire risk assessment, your NSI approved company can advise you of the most appropriate type of fire alarm system for the building.

For more information.


Learn more about fire safety for your workplace

Life Safety Fire Risk Assessments (BAFE SP205)

Portable Fire Extinguishers (BAFE SP101)

Emergency Lighting (BAFE SP203-4)

Kitchen Fire Protection Systems (BAFE SP206)

Fixed Gaseous Suppression Systems (BAFE SP203-3)

Evacuation Alert Systems (BAFE SP207)

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