Fire Detection and Alarm Basics

A reliable fire detection and alarm (FD&A) system is vital to protecting life and property. Whether your premises are large or small, these systems give early warning of danger and allow safe evacuation before fire spreads.

This guide explains what your system does, how to ensure it remains effective, and where to find more detailed advice on managing false alarms.

How fire detection and alarm systems work

Fire detection and alarm systems are designed to detect heat, smoke, or flames and then warn occupants through audible and visual signals. When a detector activates, the system triggers alarms and, where installed, sends a signal to an Alarm Receiving Centre (ARC) or the Fire & Rescue Service.

A compliant system should:

  • Detect fires quickly and accurately
  • Warn people in time for safe evacuation
  • Identify the location of the alarm on a control panel
  • Be installed and maintained to BS 5839-1 standards

Your system may be manual (activated by a break-glass point), automatic (triggered by detectors), or a combination of both.

 

Understanding system zones and categories

To make alarms easier to manage, most systems are divided into zones. Each zone covers a specific area of your premises, helping you identify where an alarm has activated.

Systems are also classified by category, which determines their coverage and purpose:

  • Category L systems protect life (L1–L5)
  • Category P systems protect property (P1–P2)

A competent fire alarm company can confirm which system category best suits your building type and occupancy.

 

Maintaining your fire alarm system

Regular servicing is essential. A fire alarm system that is not maintained can give false signals or fail to detect a real fire. Maintenance must be carried out by a third-party certified provider, ideally registered with BAFE or LPCB, in accordance with BS 5839-1.

Your responsibilities include:

  • Keeping maintenance records in your fire log book
  • Scheduling routine service visits
  • Reporting any faults immediately
  • Acting on engineer recommendations promptly

Well-maintained systems keep people safe and help you stay compliant with the Regulatory Reform (Fire Safety) Order 2005.

Also in this section

Prevent and Manage False Alarms
Evacuation Plan and Response
Competence and Third-Party Certification for Buyers

Reducing false alarms

False alarms cause disruption, cost, and complacency. Most are preventable with the right system design, maintenance, and user awareness.

You can:

  • Ensure detectors are correctly located and suitable for their environment
  • Keep areas clean to reduce dust or steam interference
  • Train staff on correct fire alarm procedures
  • Investigate and record every alarm activation

For detailed guidance, see Prevent and Manage False Alarms.