What is GS38?
GS38 is the HSE guidance note on electrical test equipment. Safe isolation uses a GS38-compliant voltage indicator, proved on a known source before and after testing to confirm it is working.
HSE GS38 · EAWR 1989
Electrical Isolation Certificate App (Safe Isolation Record)
Fill it in on site, sign on screen, and send a professional Isolation PDF before you leave the job.
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Need a Isolation for your own property? It's issued by the tradesperson who does the work — TradePlanr is the app they use.
A safe isolation certificate records that a circuit or item of equipment was isolated, secured against being switched back on, and proved dead before anyone worked on it. It is the evidence that safe isolation was carried out in line with the Electricity at Work Regulations 1989 and HSE guidance note GS38.
TradePlanr lets you complete the record on site: the point and means of isolation, the lock-off and warning notice, and the full prove-dead sequence — proving your voltage indicator on a known source before and after testing line to line, line to earth and neutral to earth.
Sign on screen and issue a branded PDF for the job file or the client's records.
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What it covers
- The circuit or equipment isolated and the location of the work
- The point and means of isolation (MCB off, isolator, fuse removed, breaker)
- Securing the isolation: lock-off, lock/tag ID, warning notice and who holds the key
- Proving dead to GS38: voltage indicator, proving unit, and proved-before / proved-after
- Confirmation the circuit was dead at the point of work
- Re-energisation details on completion
When it's required
Safe isolation is required before working on or near any electrical equipment that could otherwise be live, under the Electricity at Work Regulations 1989.
A written isolation record is good practice on commercial and industrial sites, for permit-to-work systems, and wherever you need to demonstrate the isolation was carried out correctly.
How to issue it in TradePlanr
- 1
Record the isolation
Note the circuit or equipment, the point and means of isolation, and the reason for the work.
- 2
Secure it
Confirm the lock-off, tag ID and warning notice, and who is holding the key.
- 3
Prove dead (GS38)
Record proving your indicator on a known source before and after, and the dead readings at the point of work.
- 4
Sign and issue
Sign on screen and produce a branded PDF; record re-energisation on completion.
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
Do I legally need an isolation certificate?
Safe isolation itself is a legal requirement before working on equipment that could be live. A written certificate is the record that proves it was done, and is commonly required on commercial sites and permit-to-work systems.
Related certificates
Electrical Danger Notification
The notification issued on the spot when a C1 or C2 dangerous condition is found.
Electrical Installation Condition Report (EICR)
The periodic inspection report for existing installations, with observations and codes.
Minor Electrical Installation Works Certificate
The BS 7671 MEIWC for additions and alterations that do not create a new circuit.
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