When you receive an Electrical Installation Condition Report, the section that matters most is the observations schedule. Every defect or concern found during the inspection is assigned a code — C1, C2, C3, or FI — and these codes determine what you must do next, how quickly you must act, and whether your installation is deemed satisfactory overall. Misunderstanding these codes can lead to unnecessary panic, or worse, dangerous complacency.
C1 — Danger Present
A C1 code means there is an immediate danger that could cause injury. Examples include exposed live conductors, missing earth connections on Class I equipment, or a consumer unit that is actively overheating. When a C1 is found, the electrician has a duty to make the circuit safe immediately, usually by isolating it and fitting a warning label. You should not use the affected circuit until remedial work is completed.
C1 codes are rare in well-maintained properties but common in older homes where DIY modifications have been made, or in rental properties where tenants have damaged accessories. They are also seen in commercial premises where temporary supplies have been installed incorrectly.
C2 — Potentially Dangerous
A C2 code indicates a condition that is not immediately dangerous but could become so. Examples include an RCD that fails to trip within the required time, inadequate earth bonding on a gas pipe, or a socket outlet mounted on a combustible surface without adequate protection. While you can continue using the installation, remedial work is required urgently.
The distinction between C1 and C2 is important. A C2 is not an emergency, but it should be treated as a high priority. Most insurance companies and mortgage lenders will want to see evidence that C2 defects have been resolved within 28 days of the report being issued.
C3 — Improvement Recommended
C3 codes are advisory. They indicate that the installation does not meet the current edition of BS 7671 in some way, but the deviation does not present a safety risk. Examples include the absence of surge protection in a domestic property, or a consumer unit that predates the 2016 metal enclosure requirement but is otherwise in good condition.
You are not legally required to act on C3 codes, and they do not make the installation unsatisfactory. However, addressing them when you next have electrical work done is sensible, particularly if you are planning to sell the property or install high-value equipment such as an EV charger or solar panels.
FI — Further Investigation Required
An FI code means the inspector has found something that cannot be fully assessed without additional work. This might include a circuit that cannot be traced due to buried junction boxes, or a distribution board with no circuit chart, making it impossible to confirm what each breaker protects. FI codes also render the installation unsatisfactory until the investigation is completed.
Expert Tip
If your EICR contains any C1, C2, or FI codes, the overall assessment is unsatisfactory. You must take action within 28 days for rental properties, and it is strongly recommended for all other premises. D3C Electrical provides a same-day remedial quotation service so you know exactly what needs to be done and how much it will cost.
What Is a Satisfactory EICR?
An installation is deemed satisfactory only when the EICR contains exclusively C3 codes or no codes at all. In practice, most installations over ten years old will have at least one C3. This is normal and expected. The key point is that there are no C1, C2, or FI observations that create an obligation to carry out urgent work.
At D3C Electrical, we take the time to explain every code on your report in plain English. We provide photographs of each observation, a written explanation of why the code was assigned, and a detailed quotation for any remedial work. Our goal is to give you complete clarity so you can make an informed decision.