EICR Classification Codes
Understanding C1, C2, C3, and FI codes on condition reports
BS 7671, IET Guidance Note 3 & Best Practice Guide 4
What is an EICR?
An Electrical Installation Condition Report is a formal assessment of an existing electrical installation. The inspector records observations using classification codes to indicate the severity of any defects found. Since 2020, EICRs are mandatory for private rented properties in England, Scotland, and Wales.
Classification Codes
Risk of injury. Immediate remedial action required.
Action Required
Notify the client immediately. Isolate or make safe before leaving site.
Examples
- - Exposed live parts accessible to touch (missing CU blanks)
- - Severely damaged cable with bare conductors visible
- - Incorrect polarity at the origin of the installation
- - Evidence of arcing or overheating at terminals
- - Socket-outlet smashed exposing internal terminals
Urgent remedial action required.
Action Required
Advise the client safety is not at immediate risk but requires urgent attention.
Examples
- - Missing main protective bonding to gas/water services (Reg 411.3.1.2)
- - No RCD protection on circuits serving outdoor equipment
- - Undersized cable for the load / incorrect protective device
- - Obsolete consumer unit (rewireable fuses, no RCD)
- - Missing earth conductor on a circuit
Improvement would enhance safety but no immediate danger.
Action Required
Record the non-compliance; advise improvement is beneficial but not mandatory.
Examples
- - Plastic consumer unit in good condition (Reg 421.1.201)
- - No additional RCD protection on internal lighting (where not required at time of install)
- - Lack of supplementary bonding in bathroom (where Reg 415.2.2 is met)
- - Absence of SPD (where not required at time of install)
- - Lack of circuit identification at distribution board
Further investigation required without delay.
Action Required
Inform the client that safety cannot be assured — investigation is mandatory.
Examples
- - Unexplained low insulation resistance reading on a circuit
- - Evidence of overheating inside distribution board (source not visible)
- - Unable to access junction box to verify connections
- - Cannot confirm earth path continuity to a buried cable
- - Suspected rodent damage behind walls
Overall Assessment
| Outcome | Meaning | Note |
|---|---|---|
| Satisfactory | No C1 or C2 codes recorded. Installation is safe for continued use. | C3 and FI codes may still be present |
| Unsatisfactory | One or more C1, C2, or FI codes recorded. Remedial work needed. | Client must be notified and remedial work recommended |
Recommended Inspection Frequencies
Based on IET Guidance Note 3, Table 3.2. An inspector may recommend a shorter interval if the installation is in poor condition.
| Premises Type | Routine Check | Maximum Interval |
|---|---|---|
| Domestic (general) | — | 10 years or change of occupancy |
| Domestic (rented) | 1 year | 5 years or change of occupancy |
| HMOs / halls of residence | 1 year | 5 years or change of occupancy |
| Educational | 6 months | 5 years |
| Commercial (offices/shops) | 1 year | 5 years |
| Industrial / factories | 1 year | 3 years |
| Medical locations | 6 months | 1 year |
| Swimming pools | 4 months | 1 year |
| Construction sites | 3 months | 3 months |
| Petrol filling stations | 1 year | 1 year |
Landlord Legal Requirements by UK Region
Electrical Safety Standards (Private Rented Sector) Regulations 2020
- EICR required every 5 years
- Remedial work within 28 days if unsatisfactory
- Fines up to £30,000 for non-compliance
- Must provide copy to tenants within 28 days
Housing (Scotland) Act 2006 — Repairing Standard
- EICR required every 5 years
- Applies to private and social landlords
- PAT testing also required for landlord-supplied appliances
Renting Homes (Wales) Act 2016 (in force Dec 2022)
- Valid EICR required during each occupation
- Copy to tenant within 14 days of tenancy start
- No valid EICR = property "unfit for human habitation"
- No rent payable during non-compliance
Common Coding Disputes
Reg 421.1.201 requires non-combustible CU enclosures. A plastic CU in good condition with no thermal damage is generally C3.
It becomes C2 if there is evidence of overheating, loose connections, or if it is on a sole escape route (e.g., under a wooden staircase).
30 mA RCD protection is required for all socket outlets up to 32 A and internal lighting circuits in domestic premises under current regs.
For older installations that complied at the time of design, the absence of RCD is typically C3 unless a specific high risk exists (outdoor equipment, bathrooms) — then C2.
Absence of SPDs or AFDDs in an existing installation where they were not required at the time of construction is recorded as C3. Rarely C2 unless the installation serves critical safety services or sensitive medical equipment.
Professional Observation Wording
Observations should be factual, reference the regulation, and be intelligible to a layperson while precise enough for another electrician to act on.
| Subject | Poor | Professional |
|---|---|---|
| Consumer unit | Fuse box is old and plastic. | Consumer unit enclosure is of combustible material (plastic) and is located on a primary escape route (Regulation 421.1.201). |
| Earthing | Earthing is bad. | Main protective bonding to gas and water services is missing or disconnected (Regulation 411.3.1.2). |
| Socket outlets | Sockets are loose. | Socket-outlet enclosure in kitchen is damaged, exposing live parts to touch (Regulation 416.1). |
| Circuit identification | Circuits aren't labeled. | Lack of clear identification of circuits at the distribution board (Regulation 514.8.1). |
Key Points for Inspectors
- - A single C1 or C2 code makes the entire installation Unsatisfactory
- - C3 codes alone do not make an installation Unsatisfactory
- - FI codes must be investigated — they may lead to C1, C2, or C3 once resolved
- - Judge against the edition of BS 7671 current at the time of installation, not today's edition
- - Never use the observation section as a "proposal for remedial work" — keep it factual
- - Limitations must be agreed with the client before the inspection begins
- - NICEIC Platinum Promise covers up to £25,000 if registered work is substandard
Who Can Issue an EICR?
- - NVQ Level 3 in electrical installation (or equivalent)
- - City & Guilds 2391 (or equivalent inspection and testing qualification)
- - Minimum 2 years professional experience
- - Current 18th Edition certification
- - Registered with a Competent Person Scheme (NICEIC, NAPIT, SELECT)