EICR Codes Explained: C1, C2, C3 and FI

An Electrical Installation Condition Report doesn't just say pass or fail. It lists observations about the installation and gives each one a code showing how serious it is. Understanding the codes tells you what must be fixed now, what should be fixed soon and what is advice for the future. This guide explains each code in plain English, with neutral examples of the kind of thing that might be recorded.

C1: danger present

C1 means there is a risk of injury right now. The inspector should make the situation safe immediately where possible, for example by isolating a circuit, and tell the person responsible straight away. Typical examples are exposed live parts that can be touched, such as a broken socket with conductors showing, or a damaged accessory where live metal is accessible. A C1 makes the report unsatisfactory.

C2: potentially dangerous

C2 means the installation isn't dangerous at this moment, but could become dangerous if a fault or other event occurs. It needs putting right urgently. Examples might include a missing or inadequate main protective bonding conductor, sockets that could be used for equipment outdoors without RCD protection, or signs of overheating at a connection. A C2 makes the report unsatisfactory.

C3: improvement recommended

C3 marks something that doesn't meet the current edition of the wiring regulations but isn't considered dangerous. Installations built to older editions often attract C3s simply because standards have moved on. An example might be lighting circuits without RCD protection in an older installation, where current rules would require it for new work. A C3 alone does not make the report unsatisfactory. It is advice to consider, often when other work is planned.

FI: further investigation required

FI means the inspector found something that needs investigating more than was possible within the inspection, such as test results that suggest a hidden problem on a circuit, or a circuit that couldn't be traced. Until investigated, its seriousness isn't known, so an FI makes the report unsatisfactory. The investigation may resolve to nothing, or reveal a C1 or C2.

What makes a report unsatisfactory

Any C1, C2 or FI makes the overall condition unsatisfactory. Only C3 observations, or none at all, can give a satisfactory report. The summary page states the overall result and the recommended date of the next inspection.

Remedial work

Once you know the codes, ask for a quote to put right the C1, C2 and FI items. A good quote lists each observation against the work proposed, so you can see what you are paying for. C3 items can be quoted separately as optional improvements. You can use the inspector who wrote the report or another electrician for the remedial work.

Confirmation paperwork

When remedial work is complete, the electrician issues the appropriate certificate, such as a Minor Works or Electrical Installation Certificate, or written confirmation, covering each item. Landlords in England have rules about giving that confirmation to tenants and the local authority within set periods; our guide to landlord EICR rules explains them in general terms. Our page on installation certificates explains the different documents.

Reading your own report

Look first at the summary and overall result, then the list of observations with their codes, then the schedule of test results. If any wording is unclear, ask the inspector to explain it in plain terms. Our general guide what is an EICR? covers the rest of the report.

Why codes can differ between inspectors

Coding involves professional judgement. Two competent inspectors looking at the same installation will usually agree on clear dangers, but may differ on borderline items. Industry guidance exists to keep coding consistent, and an inspector should be able to explain the reason for each code and point to the relevant requirement. If a report lists many C2 items with little explanation, it is reasonable to ask for more detail before agreeing a remedial quote.

Limitations

Every report has a limitations section describing anything that couldn't be inspected, such as rooms without access or circuits that couldn't be switched off. Read it, because a limitation can mean part of the installation hasn't been assessed at all. Arrange access so it can be covered next time.

How long codes take to fix

Remedial work ranges from replacing a single accessory to rewiring a circuit, so time varies widely. Grouping all the C1, C2 and FI items into one visit keeps disruption down.