BS 5839 and Its Application to Fire Alarm Systems
Understanding BS 5839
BS 5839 is the British Standard that provides guidance on the design, installation, commissioning, and maintenance of fire detection and alarm systems in buildings. It is an essential document for ensuring compliance with fire safety laws and best practices, particularly in non-domestic buildings such as offices, schools, hospitals, and industrial sites.
BS 5839 is divided into two key parts:
- BS 5839-1 → Covers fire alarm systems in non-domestic buildings.
- BS 5839-6 → Covers fire alarm systems in domestic premises.
This document primarily focuses on BS 5839-1, which applies to commercial and public buildings.
Why BS 5839 is Essential for Fire Alarm Systems
Compliance with BS 5839-1 is crucial because it:
- Ensures life safety by providing early fire detection and warning systems.
- Reduces property damage by enabling faster emergency response.
- Meets legal and insurance requirements, ensuring compliance with fire safety laws.
- Enhances system reliability, reducing false alarms and improving performance.
BS 5839 does not impose a legal obligation but is widely used as the standard reference for compliance with the Regulatory Reform (Fire Safety) Order 2005 (FSO) and other fire safety legislation.
Key Parts of BS 5839 Relevant to Fire Alarm Systems
Several key sections of BS 5839-1 are essential for ensuring that fire alarm systems meet safety and performance requirements.
System Categories and Coverage
BS 5839 defines fire alarm system categories based on their intended purpose:
- Category M → Manual fire alarm systems (requires manual call points, no automatic detection).
- Category L → Life protection systems (L1 to L5, based on coverage and risk levels).
- Category P → Property protection systems (P1 and P2, focusing on early fire detection to reduce property loss).
Each category specifies the required level of fire detection coverage within a building.
Design Considerations
This section outlines key factors to consider when designing a fire alarm system:
- Fire risk assessment → Identifying risks to determine appropriate system coverage.
- Detector selection → Choosing between smoke, heat, or multi-sensor detectors based on environmental factors.
- Alarm audibility requirements → Ensuring sounders and voice alarms meet minimum decibel levels for occupant warning.
- False alarm management → Implementing measures to minimize nuisance alarms and improve system reliability.
Installation Requirements
To ensure fire alarms function effectively, BS 5839 specifies strict installation guidelines:
- Cabling → Fire-resistant cables must be used and correctly routed to prevent failure in a fire.
- Power supplies → Systems must have reliable mains power and battery backup to prevent failure during outages.
- Spacing of call points and detectors → Manual call points should be positioned near exits, and detectors must be installed at appropriate intervals for full coverage.
Testing & Maintenance
Regular inspection, testing, and maintenance are essential for ensuring fire alarm systems remain operational and compliant.
- Weekly tests → The responsible person must test a manual call point every week.
- Quarterly servicing → A competent fire alarm engineer must inspect and test the system every three months.
- Annual servicing → A full system inspection must be carried out yearly to check all devices and connections.
- False alarm management → Records of false alarms must be reviewed, and appropriate actions taken to reduce unnecessary activations.
Failure to maintain a fire alarm system as per BS 5839 could lead to non-compliance with fire safety laws and insurance invalidation in the event of a fire.
Consequences of Non-Compliance
Failing to comply with BS 5839-1 can result in:
- Increased risk to life and property due to inadequate fire detection.
- Legal penalties if the system does not meet fire safety requirements under UK law.
- Higher false alarm rates, leading to potential fines or loss of trust in the system.
- Insurance disputes, as insurers may refuse claims if the system was not properly maintained.
Final Thoughts
BS 5839-1 is the foundation for designing and maintaining effective fire alarm systems in non-domestic buildings. By following its requirements, responsible persons, installers, and maintenance engineers can ensure:
✅ Compliance with fire safety laws and regulations.
✅ A reliable system that minimizes false alarms.
✅ Protection of lives and property.
Whether planning, installing, or maintaining a fire alarm system, adhering to BS 5839 is essential for safety, legal compliance, and system effectiveness.