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Fire Alarm Extension or Modification Certificate (BS 5839-1)

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Sample Fire Alarm Extension or Modification certificate

Sample Fire Alarm Extension or Modification with fictional data. All personal details shown are fake.

A Fire Alarm Extension or Modification Certificate records changes made to an existing non-domestic fire alarm system, including extensions, alterations, relocations, upgrades and control panel firmware updates. It confirms device compatibility, system testing after the work, what happened to devices taken out of use, and that the existing system remains unaffected. It covers the new work, not the conformity of the rest of the system.

BS 5839-1:2025, Regulatory Reform (Fire Safety) Order 2005Valid: One-off (for the specific modification)

What it covers

Existing system details
Modification scope and device changes
Control panel firmware versions before and after
Compatibility confirmation
Post-modification test results
Updated system information
Handover documentation updates

Who needs a Fire Alarm Extension or Modification?

Fire alarm contractors

Building owners making alterations

Facilities managers

Tenants fitting out commercial space

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Frequently asked questions about Fire Alarm Extension or Modification

Do I need a modification certificate for small changes?

Yes. Any change to a fire alarm system, including adding, removing, or relocating a single device, should be recorded on an extension or modification certificate. BS 5839-1:2025 also treats a control panel firmware update as a modification. This keeps the as-built records current and makes sure the system is retested after changes.

What about compatibility of new devices?

New devices must be compatible with the existing control panel. The modification certificate specifically records that compatibility has been confirmed and that the panel has sufficient capacity for any additions.

Learn more

Fire Alarm Certificates Explained: BS 5839 Design, Commissioning and Servicing Browse all certificate types

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