The Most Common EICR Faults We Find — And What They Mean

An Electrical Installation Condition Report doesn't just say "pass" or "fail." It lists observations, each given a code that tells you how urgent it is. Understanding those codes takes the mystery out of a report that can otherwise read like a wall of jargon.

C1 — Danger present

The most serious code. It means a risk of injury exists right now, and it should be addressed immediately — in practice, a competent engineer will often make it safe on the spot before leaving site. Exposed live parts and damaged consumer units are typical C1 findings.

C2 — Potentially dangerous

Not an immediate emergency, but a defect that could become dangerous and needs attention urgently rather than at the report's leisure. Missing earthing/bonding and overloaded circuits are common C2 findings, and a report with C2s attached is classed "unsatisfactory" until they're fixed.

C3 — Improvement recommended

Not a regulatory failure — the installation is safe to continue in use — but there's a sensible improvement that would bring it up to current standards. Older but functioning wiring colour codes are a typical C3.

FI — Further investigation required

Used when the engineer can't confirm safety without more access or testing than the inspection scope allowed — for example, a circuit that couldn't be isolated on the day.

What this means for a landlord

Only C1 and C2 findings make a report "unsatisfactory" and require remedial work before re-certification. C3s are worth doing when convenient but don't block the certificate. If a report you've received doesn't explain which codes were found and why, that's worth asking about before authorising any remedial work.