An Electrical Installation Condition Report (EICR) assesses the condition of the wiring and electrical installation in a property. When one comes back with a list of faults, the classification codes next to each observation matter enormously — they determine whether the property is deemed safe for continued use, and what work needs to be done before it is.
The problem is that not every EICR is produced to the same standard. We regularly take on remedial work for customers who’ve received a report where items have been given a higher code than the guidance warrants, or where things that shouldn’t appear on a report at all have been used to justify an unsatisfactory outcome. This guide explains what the codes actually mean, what the industry guidance says about common situations, and what to look out for if something doesn’t seem right.
What the classification codes mean
The codes used on an EICR come from a best practice guide published by Electrical Safety First, developed with NICEIC, NAPIT, ECA, SELECT and other industry bodies. There are four codes, plus two additional categories:
C1 — Danger present. There is an immediate risk of injury. Action is needed before the inspector even leaves site. Examples include exposed live conductors accessible to touch, or incorrect polarity at the origin of the installation. Any C1 code makes the overall outcome of the report unsatisfactory.
C2 — Potentially dangerous. Not currently causing harm, but would become an immediate danger if a fault occurred. Remedial action is required urgently. Common examples include absence of earthing at a socket-outlet, an RCD that fails to operate when tested, or unsatisfactory electrical connections showing signs of overheating. Any C2 code also makes the overall outcome unsatisfactory.
C3 — Improvement recommended. Not dangerous, not potentially dangerous, but the installation would be safer if the item were addressed. A C3 does not make the overall report unsatisfactory. Where a report contains only C3 observations, the outcome must be recorded as satisfactory.
FI — Further investigation advised. Used where a potential safety issue has been identified but couldn’t be fully assessed within the scope of the inspection. Rarely appropriate in domestic properties where the inspector can usually attribute a definitive code.
A C3-only report must be satisfactory
This is one of the most commonly misunderstood aspects of EICRs. If there are no C1 or C2 observations, the overall condition of the installation must be reported as satisfactory — not unsatisfactory. An unsatisfactory outcome can only be given where at least one C1 or C2 observation exists.
This matters in practice. A report listing several C3 items — things like the absence of RCD protection on a socket-outlet unlikely to be used outdoors, or an older type of RCD installed where a newer type is now preferred — is a satisfactory report. The improvements are recommended, but the property is not unsafe for continued use and there is no regulatory requirement to carry out the work before, for example, renting a property.
Things that should be C3, not C2
The distinction between C2 and C3 is frequently where errors appear. The following are C3 observations — often incorrectly escalated to C2:
Absence of RCD protection for a socket-outlet that is unlikely to supply outdoor equipment, and is not in a bathroom. This is C3. If it’s a socket in a kitchen or living room with no indication it supplies outdoor equipment, it does not warrant a C2.
A plastic consumer unit not located under a wooden staircase or within a sole escape route. The guidance is clear: plastic consumer units in that specific position are C3, not C2. A consumer unit on a hall wall away from the staircase is C3.
A Type AC RCD where a Type A is now required. This is C3 — an improvement recommended, not an urgent danger.
Absence of an RDC-DD device for an EV charge point. Also C3.
Mixed-brand switchgear in a consumer unit where there are no signs of thermal damage, the enclosure hasn’t been modified, components are securely fitted, and they operate correctly. With all those conditions met, this is C3. It becomes C2 if any of those conditions don’t hold — for example, if there are burn marks or the toggle direction differs from existing devices.
Things that don’t need a classification code at all
Some observations don’t require a C code. Non-conformities that don’t give rise to danger and where improvement is not recommended — referred to in the guidance as “NC only” — should be recorded but don’t affect the outcome. Examples include old cable colours (pre-2004 red and black wiring), switch lines that aren’t sleeved as line conductors, and undersized main bonding conductors where the conductor is at least 6mm² and shows no thermal damage.
Items can also be recorded as observations without a code where they’re noteworthy but not non-compliances — a consumer unit accessible but located at height, for example, or combustible materials near the meter.
Things that shouldn’t appear on an EICR at all
The guidance identifies a category it calls “myths” — items that are commonly reported on EICRs but are not actually non-compliances with BS 7671 and have no place in the report. Appearing as a classification code on a report, they’re simply wrong. These include:
- Rewireable fuses, where they provide adequate circuit protection. These are a legitimate means of protection under BS 7671 — an older installation with rewireable fuses is not automatically defective.
- Absence of switches on socket-outlets and fused connection units. A socket without a switch is not a fault.
- Absence of barriers inside a consumer unit, where the cover can only be removed with a key or tool. If the cover is secure, no additional internal barrier is required.
- Absence of earthing or bonding to metallic sinks and baths. This only applies where those items are extraneous-conductive-parts in their own right — which is rarely the case in modern plumbing.
- Absence of bonding to boiler pipework, where the pipework is not an extraneous-conductive-part.
- Circuit breakers to BS 3871. These are not a fault. Older MCBs that meet BS 3871 are acceptable where they provide adequate protection.
If any of these appear on your EICR with a C1, C2 or C3 code attached, the report is inaccurate on those points.
What to do if you think your EICR is wrong
If you have an EICR that has come back unsatisfactory and you’re not confident the observations are correctly classified, it’s reasonable to get a second opinion. A competent inspector should be able to explain why each code has been applied and point to the specific requirement in BS 7671 or the Electrical Safety First guidance that justifies it.
The full Best Practice Guide 4 — which covers classification codes for domestic installations — is freely available from electricalsafetyfirst.org.uk and is the document all inspectors should be following.
If you’re in Bristol or South Gloucestershire and want an EICR carried out correctly, or a second opinion on a report you’ve received, get in touch.
