EICR Codes Explained: C1, C2, C3 and FI in Plain English
You’ve had an EICR done and the report has landed — full of codes like C2 and FI. What do they actually mean, and has your installation passed or failed? Here’s the plain-English version.
First: is it satisfactory or unsatisfactory?
Every EICR ends with one overall outcome:
- Satisfactory — the installation is safe for continued use.
- Unsatisfactory — there’s at least one issue that needs attention before it can be considered safe.
What pushes a report into “unsatisfactory” is the presence of any C1, C2 or FI observation. Let’s break those down.
C1 — Danger present
Meaning: Risk of injury. Immediate action required.
This is the most serious code. It means there’s something actively dangerous right now — for example, exposed live parts. A responsible electrician will usually make it safe on the spot (with your permission) and explain what’s needed.
C2 — Potentially dangerous
Meaning: Urgent remedial action required.
A C2 isn’t dangerous this very second, but it could become dangerous — for instance, no earthing/bonding where it’s needed, or a damaged accessory. C2 items must be fixed to make the installation satisfactory.
C3 — Improvement recommended
Meaning: Not dangerous; improvement advised.
A C3 is the one people worry about unnecessarily. It does not make your report unsatisfactory. It’s a recommendation that would bring things up to the latest standards — worth considering, but not urgent or mandatory.
FI — Further investigation required
Meaning: Something needs looking into.
An FI means the inspector found something that can’t be fully assessed without more work — and it could turn out to be serious. FI items make a report unsatisfactory until they’re investigated and resolved.
A quick reference
| Code | Meaning | Affects pass/fail? |
|---|---|---|
| C1 | Danger present | Yes — unsatisfactory |
| C2 | Potentially dangerous | Yes — unsatisfactory |
| C3 | Improvement recommended | No |
| FI | Further investigation | Yes — unsatisfactory |
What to do next
If your report is unsatisfactory, don’t panic — get a clear, itemised quote for the remedial work, have it carried out, and obtain updated certification. If it’s satisfactory with a few C3s, you can plan those improvements at your own pace.
The most important thing is that you understand your report. If yours is full of codes and you’d like it explained, or you need remedial work done across Central Scotland, get in touch — I’m always happy to talk it through.
Luke Day
Qualified electrical maintenance engineer & QC Inspector, and founder of LAD Electrical Services. Specialising in inspection, testing, fault finding and maintenance across Central Scotland.
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