BS5839 Part 1 2025

The new British Standard for fire alarms in non-domestic premises (BS5839-1:2025) was released earlier this week and immediately came into force on Tuesday29th April.

There is no grace period and from the 29th of April (the day of release) BS5839:1 2025 is in-force.

These changes only apply to Part 1 systems, as BS5839:6 2019 hasn’t changed yet.

 Below is an outline of the changes to the new standard from the previous standard released in 2017.

Maintenance

The time on the control panel must be adjusted during every maintenance visit. 

Service intervals remain at 6 months but now have flexibility to be 5 or 7 months (previously, exceeding 6 months was non-compliant).

The zone chart must be verified at each service (device text is not included).

All redundant systems (old detection, call points, etc.) must be removed. 

All ‘variations’ from BS must be recorded in the fire alarm log book.

Competent persons (engineers) must now undertake continual professional development (CPD).

You can now write the battery fitted date directly on the battery with a sharpie

Using a sharpie wasn’t previously allowed so we provided labels to write on.

Design/Installation

Mains cables to fire alarm systems must be red; this requirement has been clarified.  

L4 systems now include detection at the top of lift shafts.

L2 design now includes sleeping risk in addition to specifically risk-assessed additional rooms.

All low-risk lobbies (e.g., toilet lobbies and other small lobbies) must now have detection (depending on L system specified).

Lock-down alarms can now be integrated into the fire alarm system, provided they have a distinctive tone

The formula for battery calculations has been changed to clarify it.

Clarifications have been made regarding ceiling obstructions, including duct-work and closely spaced beams.

Monitoring requirements on category L systems have been clarified: 90 seconds for signal and 3 minutes for fault.

There is now a list of items prohibited from being listed as a variation: including zone charts and monitoring in care homes

A new sticker must be placed on the front of the panel: “FALSE ALARM NOTICE This fire alarm has an active connection to fire and rescue service.