Fire Alarm Categories

There are eight main types of fire alarm categories for Grade A Fire Alarm and Detection Systems, each designed to cater to the unique requirements of your property. These requirements are dependent on a number of variables, such as the kind of property you own, the nature of your business, the kind and value of the things inside the structure, and the degree of fire risk involved. The following eight types of fire alarms:

• Category M – Manual fire alarm system
• Category L1 – Maximum life protection automated fire alarm system
• Category L2 – Additional life protection automated fire alarm system
• Category L3 – Standard life protection automated fire alarm system
• Category L4 – Modest life protection automated fire alarm system
• Category L5 – Localised life protection automated fire alarm system
• Category P1 – Maximum property protection automated fire alarm system
• Category P2 – Minimum property protection automated fire alarm system

Category M means manual fire alarm systems, and this represents the simplest form of fire alarm systems, depending on the ability of building occupants to detect a fire and initiate an alarm. In the event of a fire, it becomes the responsibility of individuals within the building to manually activate the alarm, thereby notifying others about the imminent danger.

In this setup, employees play a pivotal role in activating the alarm manually when they identify a fire.

This collective approach to safety ensures that, in the event of a fire, occupants take the initiative to raise the alarm. A common example of a manual fire alarm system is the installation of manual call points (MCPs) at exit points in a building, enabling individuals to initiate the alarm as they evacuate.

Fire alarm systems categorized as “L” are considered to be the most appropriate for ensuring the safety of occupants within a building. These systems are further classified into five sub-categories based on their efficacy levels.

Category L1 provides the highest level of fire protection, with detectors installed throughout the building in all areas where a fire could potentially start. These detectors are linked to a centralised fire alarm system, which triggers a full-building alert at the first sign of smoke or heat, ensuring immediate notification to all occupants.

Category L2 fire alarm systems are designed with smoke detectors strategically positioned along escape routes, including corridors, rooms, and high-risk areas such as kitchens, boiler rooms, and locations housing heavy machinery. These detectors provide early detection in critical areas, enhancing safety for all occupants.

This system ensures a swift warning for individuals both near and far from the fire source, particularly in high-risk zones. Commonly used in factories, industrial facilities, and medium-sized residential buildings, Category L2 is essential for safeguarding people and property through prompt fire detection.

 Category L3 fire alarm systems feature smoke detectors installed along all escape routes and in rooms that open onto these routes. Their primary purpose is to provide occupants with sufficient time to evacuate before fire, smoke, or toxic fumes block exits, ensuring safe passage during emergencies.

This system is well-suited for medium-sized office buildings and commercial properties with staircases and multiple exits, where quick detection and alerting are crucial to preventing entrapment during a fire.

Category L4 fire alarm systems focus on installing detectors in escape route areas, such as corridors and stairways. By monitoring these critical circulation spaces, the system provides early warning to ensure evacuation paths remain safe and unobstructed during a fire.

This system is ideal for low-risk properties, such as single-story office buildings, where occupants have quicker access to exits and require minimal time to evacuate safely.

Category L5 fire alarm systems are tailored to address specific fire hazards in designated areas of a building. They are ideal for rooms or zones with heightened fire risks due to stored materials or specific business operations. Often, L5 systems complement broader setups, such as Category L4, by providing targeted protection in vulnerable areas.

This customised approach ensures that high-risk zones receive focused protection, effectively mitigating fire hazards where they are most likely to occur.

The P-category fire alarm systems are aimed at protecting property. A system can be classified under this category when assessing the potential impact of fire on a business and its operations.

A P1 fire alarm system involves installing detectors in all areas of the building. This type of system is aimed at safeguarding critical facilities for business operations.

By implementing comprehensive protection throughout the site, those responsible for fire safety can quickly detect and respond to any fire incidents, reducing the risk of damage and disruption and the financial impact on the company.

A category P2 fire alarm system features fire detectors installed in high-risk areas only. Although it doesn’t offer the same coverage as a P1 system, it provides early detection of the most probable fire sources.

This early detection shortens the response time of fire services and helps to minimize property damage and business losses.

Ensuring the safety of your business premises goes beyond protecting assets—it requires compliance with fire safety regulations, specifically the Regulatory Reform (Fire Safety) Order 2005. This legislation applies to nearly all types of buildings, excluding individual private homes, and mandates that business owners meet strict fire safety standards.

A critical aspect of compliance is determining the correct fire alarm category for your premises.

The British Standard BS 5839 outlines eight fire alarm categories, divided into three main system types:

1. Manual Systems (M): Operated by individuals using call points.
2. Life Protection Systems (L): Focused on early warning for safe evacuation.
3. Property Protection Systems (P): Designed to minimise fire damage to the building and its contents.

Each category is suited to specific building types, fire risks, and operational needs, making it essential to choose the right one for your premises.

Selecting the correct fire alarm system requires a detailed assessment of:

• Building Type: Size, layout, and occupancy levels.
• Business Nature: Activities carried out and potential fire hazards.
• Contents Value: Importance of protecting valuable equipment or materials.
• Fire Risks: High-risk areas, such as kitchens or machinery rooms.

Selecting the Right Fire Alarm System

When choosing the ideal fire alarm system, factors like building size, occupancy, fire risk level, and specific requirements identified through a fire risk assessment are key considerations. Consulting with our experts at Cobra Fire and Security offers valuable guidance for an informed decision.

Optimal safety for occupants and property hinges on selecting the right fire alarm system. Acquaint yourself with various categories and their features to make an informed decision tailored to your needs. Conducting a thorough fire risk assessment and seeking professional advice from Cobra Fire and Security ensures your chosen system provides optimal protection in case of a fire.

Cobra Fire and Security possesses the knowledge to help your business meet legal requirements in fire safety, including legislation on fire alarms. Take a moment to explore our website for more articles and guides covering services like fire risk assessments, fire alarm installation and fire alarm maintenance, advisory services, and insightful articles on fire safety provisions, along with our Top Fire Safety Tips!”

Reviewed: 22/01/2025 Our articles are reviewed regularly. However, any changes made to standards or legislation following the review date will not have been considered. Please note that we provide abridged, easy-to-understand guidance. To make detailed decisions about your fire safety provisions, you might require further advice or need to consult the full standards and legislation.