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    • Home
    • System Design
    • Installation
    • Commissioning
    • Routine Maintenance
    • Fire Extinguishers
    • Fire Risk Assessments
    • Fire Training
  • Home
  • System Design
  • Installation
  • Commissioning
  • Routine Maintenance
  • Fire Extinguishers
  • Fire Risk Assessments
  • Fire Training

Fire Protection System Design

Before designing an automatic fire detection system, it is essential to define the main objectives of the fire alarm systems in place. This determination is typically made through a Fire Risk Assessment, which should be included as part of the fire system specification to ensure fire safety compliance. BS5839 categorizes fire alarm systems into three design types: M Type System - Manual Only, L Type Systems - Life Protection, and P Type Systems - Property Protection.

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DESIGN CATAGORIES

M Type System

L5 Type System

L5 Type System

Floor plan with marked fire alarm call points.

Category M systems are manual fire alarm systems that depend on the occupants of the building to discover a fire and activate the system to alert others. These systems are essential for fire safety compliance in workplaces where there is no sleeping risk. 


In addition to these manual means of triggering an alarm, L category systems typically incorporate an element of automatic fire detection, utilizing smoke or heat detectors for enhanced safety.

L5 Type System

L5 Type System

L5 Type System

Floor plan with fire alarm system components.

Category L5 systems are the 'custom' category that addresses specific requirements not covered by other classifications. When implementing fire alarm systems or automatic fire detection solutions, it is crucial to reference the objective of the cover, typically derived from a fire risk assessment, to ensure fire safety compliance.

L4 Type System

L5 Type System

Fire alarm system layout with detectors and call points in office areas.

Category L4 systems focus primarily on escape routes and circulation areas within the building. While automatic fire detection devices may be installed in other parts of the structure, the main goal remains to ensure the safety of these escape routes in compliance with fire alarm systems and fire safety compliance standards.

L3 Type System

L3 Type System

Floor plan showing fire alarm devices in offices, kitchen, canteen, and food store.

Category L3 systems offer more extensive cover than Category L4, ensuring that rooms leading onto escape routes are included. The primary goal of these systems is to utilize automatic fire detection technology to warn building occupants early enough, allowing everyone to evacuate safely before escape routes become impassable. This is crucial for maintaining fire safety compliance in any structure.

L2 Type System

L3 Type System

L2 Type System

Floor plan showing fire alarms and detectors in offices and common areas.

Category L2 systems involve automatic fire detection and are designed to provide fire alarm systems for specific areas within a building, all while also meeting the requirements of Category L3. The broader coverage aims to address parts of the building that are deemed to have a high level of risk or fire hazard, ensuring fire safety compliance.

L1 Type System

L3 Type System

L2 Type System

Fire alarm system layout with detectors and call points.

With Category L1 systems, the entire building is equipped with automatic fire detection, ensuring comprehensive coverage with minor exceptions. This setup is essential for effective fire alarm systems and maintaining fire safety compliance.

P1 Type System

P1 Type System

P1 Type System

Fire alarm system layout with sensors in various rooms.

Category P1 systems are installed throughout the building with the objective of enhancing fire safety compliance by providing the earliest possible warning of fire through effective automatic fire detection, minimizing the time between ignition and the arrival of fire fighters.

P2 Type System

P1 Type System

P1 Type System

Floor plan of a P2 fire alarm system showing various rooms.

Category P2 systems utilize automatic fire detection to monitor specified parts of the building where there is either a high risk or where business disruption must be minimized, ensuring robust fire alarm systems that contribute to overall fire safety compliance.

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