EICR C1, C2 and C3 Codes Explained: What They Mean and What to Do
When an EICR identifies faults in a London property, each observation is assigned a classification code. Understanding what C1, C2 and C3 mean is essential for landlords and homeowners who need to decide how urgently to act on the findings.
How EICR Classification Codes Work
An electrical installation condition report (EICR) records the findings of a qualified electrician who has inspected and tested all fixed electrical circuits in a property. When the electrician identifies a defect, deterioration, or departure from the current wiring regulations, each observation is assigned a classification code that indicates the severity of the issue and the urgency of the action required. The three codes used are C1, C2, and C3. A fourth designation, FI (further investigation required), is used when a suspected fault cannot be confirmed or fully assessed during the inspection and requires follow-up investigation before a classification can be assigned.
The overall result of an EICR is either satisfactory or unsatisfactory. A report containing any C1 or C2 observations must be classified as unsatisfactory overall, meaning the installation cannot be certified as safe in its current condition. A report containing only C3 observations or no observations at all may still receive an overall satisfactory result.
C1: Danger Present
A C1 classification is assigned when the electrician identifies a condition that presents an immediate danger to persons or property. Examples of C1 observations include exposed live conductors that can be touched, a protective device that has failed in a way that leaves a circuit unprotected, or an earthing arrangement so severely compromised that a fault would not be safely cleared. A C1 observation means that the risk exists right now and must be addressed immediately — it should not be left until a convenient time.
When a C1 defect is identified during an EICR, the electrician should make the installation safe before leaving the property if possible. This may involve isolating the affected circuit, capping off an exposed conductor, or in extreme cases recommending that the electricity supply is isolated entirely until the defect is repaired. A landlord who receives an EICR with a C1 observation must treat it as an emergency and arrange for a qualified electrician to carry out the remedial works as a matter of urgency before the property can be safely occupied.
C2: Potentially Dangerous
A C2 classification indicates that while there is no immediate danger in the current state of the installation, the condition identified could become dangerous under foreseeable circumstances. Examples of C2 observations include inadequate earthing or bonding on a circuit, a protective device that is not correctly rated for the circuit it protects, an absence of RCD protection on circuits that current regulations require to be RCD-protected, or deteriorated cable insulation that has not yet failed but is at risk of doing so.
A C2 observation does not require the electrician to make the installation immediately safe in the way a C1 does, but it does mean the overall EICR result is unsatisfactory and remedial works must be carried out. For landlords in England, an EICR containing C2 observations must have the remedial works completed within 28 days of the inspection report date, or sooner if the report specifies a shorter timescale. The landlord must provide written confirmation to the local authority that the works have been completed if requested.
C3: Improvement Recommended
A C3 classification indicates that while the installation complies with the regulations in force at the time it was installed, it does not meet the current edition of the wiring regulations and would benefit from improvement. C3 observations do not make the overall EICR result unsatisfactory on their own, and they do not carry a legal obligation to remediate within any specific timeframe. Examples include wiring installed to older standards that has not been updated, or protective measures that were acceptable at installation but are no longer considered best practice.
Although there is no compulsion to act on C3 observations immediately, they represent a considered recommendation from the inspecting electrician. Addressing C3 observations at the same time as any C1 or C2 remediation is often cost-effective, since the electrician is already working on the installation. Leaving C3 observations unaddressed at successive five-yearly EICR inspections increases the risk of them deteriorating into C2 conditions over time.
What to Do After Receiving an EICR with Observations
When you receive an EICR containing C1 or C2 observations, the correct sequence of actions is: review the report with the inspecting electrician to confirm your understanding of each observation; obtain a quote from a qualified electrician for the remedial works; have the works completed within the required timeframe; obtain written confirmation from the electrician that the works are complete; and retain copies of the original EICR and the completion confirmation for your records. If the EICR result was unsatisfactory, a follow-up inspection confirming satisfactory remediation can be used to demonstrate compliance to a local authority or managing agent. Prestige Engineers carry out EICR inspections and remedial works for London landlords and homeowners, providing clear explanations of all observations and competitive pricing for both inspection and remediation.