Updated fire alarm standard implemented 30 April 2025

The revised BS 5839-1:2025, the British Standard for fire detection and fire alarm systems in non-domestic premises came into effect on 30 April 2025. The standard outlines best practice for the design, installation, commissioning and maintenance of fire alarm systems.

What is BS 5839-1:2025 About?

BS 5839-1 is a code of practice rather than a legal requirement to install fire alarms in specific buildings. It is, however, widely referenced in Approved Document B and used by regulatory authorities, enforcement bodies and insurers when assessing fire safety provisions.

The standard applies to non-domestic buildings and is intended for those involved in system design, installation, maintenance and commissioning, including fire engineers, consultants, H&S managers and systems integrators.

What’s Changed in the 2025 Revision?

This latest update supersedes BS 5839-1:2017 and was developed ahead of schedule to reflect lessons learned from recent fire incidents, including a 2022 Prevention of Future Deaths letter following a fatal care home fire.

Key changes include:

• Cause-and-effect matrix now required at system handover (Clause 6.3.6)
• Stricter control on variations – Some deviations are now explicitly prohibited due to safety concerns (Clause 6)
• False alarm monitoring – New requirements for logging, investigating, and acting on false fire signals (Clauses 29–33)
• Improved guidance on detector siting – Especially for voids, stairwells, lobbies, and escape routes (Clauses 21.1 & 22)
• Automatic fire detection now preferred in sleeping accommodation (Clause 22.3)
• Manual call point placement guidance simplified
• Zone plans – Missing or incorrect plans now classed as a major non-conformity (Clause 40)
• Cyber security measures added for remote access systems (Clause 21.2)
• New Section 7 introduced for extensions and modifications
• Clause restructuring – Clause 4 moved to the Introduction; Clause 33 merged with Clause 31

Further Learning & Resources

Download the FIA Guide to the Changes
The Fire Industry Association has published a helpful overview of the new standard:
Download the Guide

Take the Online Seminar
The FIA is offering an online, CPD-accredited seminar covering the key updates to BS 5839-1:2025.
The seminar can be taken at any time – the dates listed are for registration and administration purposes only.

• £20 per registration
• A Certificate of Completion is issued upon successful completion of the online test
• Organisations with 10 or more learners can access discounted rates – contact training@fia.uk.com to enquire.

Find out more and register here:

Access the Full Standard at a Discount
ISCVE members can purchase the full BS 5839-1:2025 document at a discounted rate via our BSI agreement.
Contact us at info@iscve.org.uk  for details.