EICR coding
EICR code checker (C1, C2, C3, FI)
Pick a common observation to see the classification code it usually attracts and why. Coding is always the inspector's judgement on the day. This is a guide, not a ruling.
Based on Electrical Safety First Best Practice Guide 4 and common industry consensus. The final code is the inspecting electrician's responsibility.
C1 Danger present. Risk of injury. Immediate remedial action required.
C2 Potentially dangerous. Urgent remedial action required.
C3 Improvement recommended (does not make the report unsatisfactory).
FI Further investigation required without delay.
How EICR coding works
An EICR is only as useful as its coding, and the four codes carry different weight. A report is unsatisfactory if it contains any C1, C2 or FI. A report with only C3 observations is satisfactory. A landlord, agent or buyer reads that line first, so the code matters as much as spotting the defect.
What each code means
- C1, danger present: someone could be hurt now, such as exposed live parts. Make safe before you leave.
- C2, potentially dangerous: safe until a fault occurs, such as missing earthing or bonding.
- C3, improvement recommended: below current standard but not dangerous. It does not fail the report.
- FI, further investigation: something needs opening up or testing before it can be coded.
Judgement, not a lookup
This tool follows the consensus in Electrical Safety First Best Practice Guide 4, but the guidance is clear that coding is the inspector's judgement in context. The same defect can be C2 in a wet plant room and C3 in a dry domestic cupboard. Use the checker to sanity-check your thinking, not to make the decision. You sign the report. Pair it with the max Zs checker for the tests behind the observations.
FAQs
What do C1, C2 and C3 mean on an EICR?
C1 means danger is present and immediate action is required. C2 means potentially dangerous and urgent action is required. C3 means improvement is recommended. FI means further investigation is required. C1, C2 and FI make a report unsatisfactory. C3 does not.
Who decides the EICR code?
The inspecting electrician, using professional judgement and guidance such as Electrical Safety First Best Practice Guide 4. This tool reflects common consensus but does not replace that judgement.
Is a plastic consumer unit a C2 or C3?
On its own, with no other defect, a plastic (combustible) consumer unit in domestic premises is generally coded C3, improvement recommended, not C2.