Troubleshooting & Advice
What Is the Difference Between C1, C2 and C3 on an EICR?
C1 is immediate danger, C2 potentially dangerous, C3 improvement recommended. Here is what each means and what you must do.
By Steels Electrical · 4 June 2026 · 4 min read
The short answer
On an EICR, C1 means danger is present and there is a risk of injury — immediate action required. C2 means potentially dangerous — urgent remedial work needed. C3 means improvement recommended — not dangerous, no action legally required. FI means further investigation is needed. Any C1, C2 or FI makes the report “unsatisfactory”; C3 on its own does not.
EICR codes confuse a lot of people, especially landlords trying to work out whether they have to act. Here is what each code means in plain terms.
What each code means
The inspector assigns one of these to any issue found:
- C1 — Danger present. Risk of injury; immediate action required (the inspector usually makes it safe on the spot).
- C2 — Potentially dangerous. Remedial work needed urgently.
- C3 — Improvement recommended. Not dangerous; no obligation to act, but worth doing.
- FI — Further investigation required without delay.
Which codes make a report unsatisfactory
A report is marked “unsatisfactory” if it contains any C1, C2 or FI. Those must be put right — for landlords, within 28 days, with written confirmation. A report with only C3 items is “satisfactory”, though acting on the C3s still improves the installation.
Frequently asked questions
- Do I have to fix C3 items?
- No. C3 is advisory — the installation is safe. They are improvements worth considering, but they do not make the report unsatisfactory and there is no legal duty to act.
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