When do I need a modification certificate?
Whenever an existing fire alarm system is altered or extended — for example adding detection to a new area, or relocating devices — to record the change and confirm the existing system is not impaired.
BS 5839-1
Fire Alarm Modification Certificate App (BS 5839-1)
Fill it in on site, sign on screen, and send a professional FA Modify PDF before you leave the job.
Free to build · Send it with a 7-day free trial
Need a FA Modify for your own property? It's issued by the tradesperson who does the work — TradePlanr is the app they use.
When an existing fire detection and alarm system is altered — devices added, removed or relocated, or a new area brought into use — a modification certificate records the change and confirms it does not impair the existing system.
TradePlanr captures the description and reason for the modification, the areas affected, the cause and effect update and retest, and whether the system category is unchanged.
Sign on screen and issue a branded PDF for the system's log book and documentation.
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- 7-day
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What it covers
- The control panel, category and type of the existing system
- A description of the modification and the reason for it
- The areas or zones affected and the devices added, removed or relocated
- Cause and effect updated and the affected devices retested
- Whether the system category is unchanged, or the revised category
- Confirmation the system was left fully operational
When it's required
A modification certificate is issued whenever an existing fire alarm system is altered or extended.
It records that the change was carried out to BS 5839-1 and does not impair the safety of the existing system.
How to issue it in TradePlanr
- 1
Record the system
Add the existing panel, category and type of system.
- 2
Describe the change
Record the modification, the reason, the areas affected and the devices changed.
- 3
Update and retest
Confirm the cause and effect was updated, the affected devices retested and the documentation updated.
- 4
Sign and issue
Sign on screen and produce a branded PDF for the log book.
Issue this certificate from your phone or the web
TradePlanr generates this and 79 other gas, electrical, oil, plumbing and renewables certificates as proper PDFs — filled on site, signed on screen and stored against the job. Works even with no signal. Free to start.
Frequently asked questions
Does a modification change the system category?
It can. The certificate confirms whether the category is unchanged, or records the revised category if the modification alters the system's coverage.
Related certificates
Fire Alarm Inspection & Servicing Certificate
The periodic inspection and servicing certificate for fire alarm systems under BS 5839-1.
Fire Alarm Commissioning Certificate (BS 5839-1)
The BS 5839-1 commissioning certificate confirming the system was tested and commissioned.
Fire Alarm Device List (BS 5839)
A schedule of every fire detection and alarm device by zone, location and address.
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