Source note. This article is based on the Fire Industry Association's published summary of the changes, Guide to the changes in BS 5839-1:2025 (Version 1, June 2025). It has not been checked line by line against the text of BS 5839-1:2025 itself, which is the authoritative document. Check clause wording in the standard before relying on it in a contract, certificate or dispute. The standard applies to the UK; other countries use different codes.
Section 7: extensions and modifications
The FIA reports that BS 5839-1:2025 adds a new Section 7, which incorporates the former clause 46 of the 2017 edition and adds a new clause on extensions. Points it highlights:
- Extensions. New work should comply with the current version of the standard. The standard acknowledges the overall system might not conform to it.
- Certificate. The certificate issued after work is now an extension or modification certificate, rather than a modification certificate.
- Firmware. Updating the firmware of a control panel is a modification, so it needs a certificate.
- Redundant equipment. Where equipment is no longer in use after a modification, the FIA says redundant devices should be removed where practicable, or clearly identified as no longer in use, to avoid confusion.
The firmware point is the one most likely to catch people out, because it is often treated as routine maintenance.
Agreed variations
The FIA describes a new approach to variations: not every variation is permitted any more, and all variations need justification, especially if proposed at installation or commissioning. All agreed variations should be recorded in the system logbook. The 2017 edition recommended recording only major variations, with no definition of major.
Logbook and documentation
- The logbook clause has been updated to recommend recording all variations, and the model logbook format has moved from Annex F in 2017 to Annex H in 2025.
- A cause and effect matrix, or a text description of how cause and effect operates, is now recommended within the documentation for the purchaser or user. The FIA notes this could be as simple as stating that the system is a simultaneous evacuation, or a full matrix for a complex strategy.
- The commissioning engineer should tell the user it is important to keep documentation up to date and available to interested parties.
Practical points
- Add firmware updates to your job types so a certificate is raised each time.
- Mark or remove redundant devices on the zone plan and on site.
- Keep every agreed variation and its justification in the logbook, with the date.
- Hand over a cause and effect description even for simple systems.
See the maintenance schedule for how these records feed the servicing routine, and servicing under BS 5839-1:2025.
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Scope
This article covers BS 5839-1 as used in the UK. Other countries use different standards for modification control and record-keeping, and this article does not describe them.