BS 5839-1:2025 – What You Need to Know About the Latest Fire Alarm Standard in the UK
On 30th April 2025, the British Standards Institution introduced the latest version of BS 5839-1, updating the 2017 edition. This new standard outlines the current best practices for the design, installation, commissioning, and maintenance of fire alarm systems in UK non-domestic buildings.
What is BS 5839-1?
BS 5839-1 is the established British Standard governing fire alarm systems in commercial and other non-residential properties. It is referenced within the Building Regulations’ Approved Document B and details everything from system types and component placement to performance criteria and upkeep procedures—ensuring occupant safety and compliance with legal requirements.
Key Changes in the 2025 Edition
- Detector Preferences in Sleeping Areas
The standard now recommends smoke detectors rather than heat detectors for sleeping areas such as hotels, care homes, and student residences to ensure quicker detection. - Expanded Scope for System Categories
Lift shafts must now be covered under L4 category systems, and detection is also required in low-risk lobby areas depending on the system classification. - Improved Manual Call Point Guidance
The updated rules specify that manual call points should be placed in frequently used areas, improving accessibility and helping reduce false alarms. - Lockdown Alarm Tone Addition
Fire alarm panels may include a separate lockdown tone, but it must be easily distinguishable from fire alarm signals to avoid confusion. - Consideration for Ceiling Obstructions
Installers are now required to account for ceiling structures like beams or ductwork that may block detector coverage, preventing blind spots. - Quicker Monitoring Response
Automatic fire detection systems must send activation alerts within 90 seconds and fault signals within three minutes, speeding up response times. - Updated Battery and Cable Requirements
Red mains cabling is now compulsory for clear identification, and the battery backup calculation method has been revised, meaning existing systems need re-evaluation. - Focus on Visual Alarm Devices (VADs)
There is increased emphasis on VADs to better accommodate those who are deaf or hard of hearing. - Mandatory Zone Plans for Multi-Zone Sites
Clear, displayed zone plans are now required near control panels in buildings with multiple fire zones to aid rapid emergency responses. - New Requirements for Residential Care Facilities
Fire alarms in residential care settings must automatically alert central monitoring stations to ensure immediate action. - Flexible Servicing Intervals and Enhanced Maintenance
The servicing window has been adjusted to allow 5 to 7 months between inspections instead of a fixed 6 months. Maintenance must include tasks such as clock synchronization, log updates, removal of obsolete equipment, and keeping control interfaces accessible. Professionals must also maintain Continuing Professional Development (CPD). - Updated Documentation and Certificates
All paperwork, logs, and certificate formats have been refreshed. Any changes to fire alarm systems must now be backed by formal Modification Certificates, with all variations clearly documented.
Why These Updates Matter
The revisions in BS 5839-1:2025 focus on enhancing life safety through:
- Faster and more reliable detection, particularly in sleeping quarters
- Greater flexibility and clarity in maintenance and servicing
- Improved inclusivity for people with hearing impairments
- Higher standards for documentation and technician qualifications
Keeping up with the latest BS 5839-1 guidance is essential for anyone involved in fire safety management within UK commercial or residential care environments. These changes reflect current best practices designed to protect lives and property more effectively.
