An EICR (Electrical Installation Condition Report) is carried out in a fixed sequence set out in BS 7671 Chapter 65 and IET Guidance Note 3: gather information and agree the extent and limitations with the client, carry out a visual inspection using the schedule of inspections, then test in the GN3 order (dead tests before live tests), record the results on the schedule of test results, classify every defect as C1, C2, C3 or FI, give an overall Satisfactory or Unsatisfactory assessment with a recommended next-inspection interval, and sign and issue the report. This guide walks through each stage as a working inspector would.
- Agree extent and limitations before you touch anything, and write them down.
- Dead tests first, live tests second, and prove safe isolation before every dead test.
- Sampling is allowed but must be representative, recorded, and increased if you find defects.
- Every observation needs a location, a description, a code and ideally a regulation reference.
- The report is only complete when the schedules, observations, summary and signature all agree with each other.
What do you need before you start an EICR?
Pre-inspection information
BS 7671 Regulation 651.1 and GN3 both expect the inspector to gather what is available before arriving. Ask the client or agent for:
- Previous EICRs, EICs and Minor Works certificates, with their schedules of test results.
- Any circuit charts or distribution board schedules.
- Details of alterations since the last report.
- Known problems (tripping, flickering, burning smells).
- Access arrangements: keys, tenants, lofts, locked plant rooms, outbuildings.
- The purpose of the report (landlord compliance, sale, insurance, change of use) because it affects the extent you agree.
Previous test results matter because periodic inspection is about deterioration: a Zs that has gone from 0.4 Ω to 0.9 Ω is a story; the same reading alone is just a number.
Instruments and documents
You need a calibrated multifunction tester (MFT), a GS38-compliant voltage indicator and proving unit, lock-off kit, and the model EICR form from BS 7671 Appendix 6 or a scheme/app equivalent. Check test leads and probes before the job, not on site.
How do you agree the extent and limitations?
The extent is what the report covers: which boards, circuits and parts of the building. The limitations are what was agreed in advance would not be done, plus anything discovered on the day that could not be done.
Agree with the person ordering the report, before starting:
- Which boards and circuits are included (all of them, for a normal domestic).
- The sampling percentage for accessories (commonly 10 to 20 per cent of accessories on each circuit for a domestic, increased where defects are found).
- Whether circuits with critical loads (fridge-freezers, servers, life support, alarms) can be isolated.
- Whether cables concealed in walls, floors and ceilings will be inspected (usually not, other than where visible).
- Whether lofts, voids, outbuildings and locked areas will be accessed.
Record all of this in the "Extent and limitations" section. GN3 accepts limitations agreed with the client; limitations invented afterwards to explain a thin report are not acceptable. Any limitation that stops you determining whether something is safe should produce an FI observation, not silence.
How do you carry out the visual inspection?
The visual inspection is done against the schedule of inspections in the EICR form, which lists the items to check for the intake, the earthing and bonding, the consumer unit, the final circuits, and special locations. It is done with the supply on for the parts you can see, and then with the consumer unit cover off after safe isolation. The main items are:
Supply and intake - Earthing arrangement (TN-C-S, TN-S, TT), main switch, main fuse, meter tails. - Earthing conductor and main protective bonding: present, correctly sized (Sections 542 and 544), connected and labelled.
Consumer unit or distribution board - Enclosure material and condition (Reg 421.1.201 for domestic), damage, signs of overheating. - Protective devices: type, rating, suitability for the circuit and for the prospective fault current. - RCD provision for sockets (411.3.3), lighting in domestic premises (411.3.4), cables in walls (522.6.203), bathrooms (Section 701). - Circuit chart present and accurate (Reg 514.9). Labels, warning notices, RCD test notice. - Terminations, conductor identification, no borrowed neutrals visible.
Final circuits and accessories - Sampled accessories opened: condition, terminations, cpc connected and sleeved, polarity. - Cable types, support (Reg 521.10.202), safe zones, mechanical protection, signs of overheating or DIY alteration.
Special locations - Bathrooms (Section 701): zones, IP ratings, supplementary bonding or the conditions that allow its omission. - Outdoor, EV charging (Section 722), solar PV (Section 712) if present.
Photograph every observation and the board with the cover off. Photographs settle arguments later.
What is the correct testing sequence for an EICR?
GN3 sets the order for safety: the dead tests prove the installation is safe to re-energise before the live tests.
Safe isolation
Before every dead test: identify the circuit, isolate, lock off, prove the voltage indicator, test dead (all conductors to each other and to earth), prove again. This is the GS38 procedure and it is not optional. Tell the occupier why the power is going off.
Dead tests
| Order | Test | What it proves | Typical minimum / acceptance |
|---|---|---|---|
| 1 | Continuity of protective conductors (R1+R2) and main/supplementary bonding | Every exposed and extraneous conductive part is connected to earth | Value consistent with cable length and csa; bonding typically ≤0.05 Ω |
| 2 | Continuity of ring final circuit conductors (r1, rn, r2, then figure-of-eight) | Ring is continuous with no interconnections or breaks | End-to-end readings consistent; cross-connected readings substantially equal at each socket |
| 3 | Insulation resistance | No breakdown of insulation between live conductors and to earth | ≥1 MΩ at 500 V DC for circuits up to 500 V (Reg 643.3.2); anything below 2 MΩ warrants investigation |
| 4 | Polarity (dead) | Single-pole devices are in the line conductor, terminals correctly connected | Confirmed at each sampled point |
On a periodic inspection, insulation resistance is usually tested line and neutral together to earth to avoid damaging connected equipment; test line to neutral with loads disconnected if the reading is low. Switch off anything electronic (dimmers, smart switches, boiler controls, SELV drivers) before testing at 500 V.
Live tests
| Order | Test | What it proves | Typical acceptance |
|---|---|---|---|
| 5 | Earth fault loop impedance (Ze at the origin, Zs at circuit ends) | Fault current is enough to operate the protective device in time | Zs ≤ 80 per cent of the maximum in BS 7671 Chapter 41 tables (the 0.8 rule of thumb for temperature correction) |
| 6 | Prospective fault current (PFC / PSCC) | Protective devices can safely interrupt the fault | Ipf below the breaking capacity of every device |
| 7 | Polarity (live) | Confirms live polarity at the origin and at points that could not be dead-tested | Correct at every point checked |
| 8 | RCD operation | RCDs disconnect within the required times | 30 mA RCD: trip at 1× IΔn within 300 ms; at 5× IΔn within 40 ms where additional protection is provided; no trip at ½× IΔn |
| 9 | Functional testing | Switches, isolators, RCD test buttons, interlocks operate | All operate as intended |
Record Ze, PFC at the origin, nominal voltage and earthing arrangement in the supply characteristics section. Maximum Zs figures come from the BS 7671 Chapter 41 tables for the device type and rating; see maximum Zs values.
How do you fill in the schedule of test results?
The schedule of test results is one line per circuit, per distribution board. For each circuit record:
- Circuit number and description (what it actually feeds, not what a wrong label says).
- Wiring type, reference method, live conductor and cpc csa.
- Protective device: BS (EN) number, type, rating, breaking capacity; RCD rating, IΔn and type where fitted.
- Maximum permitted Zs for that device.
- Continuity: R1+R2 or R2, and r1, rn, r2 for ring finals.
- Insulation resistance: L-L (where tested), L-E, N-E.
- Polarity confirmed, measured Zs, RCD times at 1× and 5×, test button operated.
- Remarks, such as "IR L+N to E, loads connected".
Fill in the schedule as you go, circuit by circuit, not from memory in the van. Readings transposed to the wrong circuit are the most common EICR error and almost impossible to spot afterwards. Column-by-column guidance is in schedule of test results: how to fill in.
How do you code the observations?
Every defect found is entered in the observations section with a code: C1 danger present (make safe before leaving), C2 potentially dangerous, C3 improvement recommended, FI further investigation required. Any C1, C2 or FI makes the report Unsatisfactory. The accepted references for applying the codes consistently are IET GN3 and Electrical Safety First Best Practice Guide 4; the EICR codes guide gives 25+ worked examples. When writing each observation, give the location, the finding, the regulation where you are sure of it, and the code. One item per line. If you have made a C1 safe, say what you did.
Cross-check: every low IR value, high Zs, failed RCD test and missing cpc on the schedule should have a matching observation, and every observation about a circuit should appear in that circuit's remarks.
How do you complete the summary and sign off?
The summary section has three parts:
- General condition of the installation: a few plain sentences. Age, apparent history of alteration, overall standard of workmanship, any pattern (for example, "several DIY additions to the ring final circuits, all without RCD protection").
- Overall assessment: Satisfactory or Unsatisfactory. This must agree with the observations. If there is a C2 anywhere, the box says Unsatisfactory.
- Recommended interval to the next inspection: from Regulation 653.2 and the GN3 tables (5 years for rented domestic as the legal maximum, 10 years owner-occupied, 3 years industrial and so on; see how often is an EICR required). Where the report is Unsatisfactory, make the recommendation conditional on the remedial work.
Then the declaration: the inspector signs as the person carrying out the inspection and testing, with a second signature from the person authorising issue where a company issues the report. Include name, position, company, scheme registration number and inspection dates. Attach both schedules for every board; the report is not valid without them.
How do you issue the report?
Issue the complete report (all pages, all schedules, photographs if included) to the person who ordered it, promptly. For a rented property in England the landlord then has 28 days to give it to the tenant and, if Unsatisfactory, 28 days to complete remedial work; see the landlord requirements guide. If you found a C1 you could not make safe, put that in writing to the client on the day. Keep your own copy with photographs and raw readings; scheme assessors ask for sample reports at every visit.
How Certio helps
Certio produces the EICR, EIC, Minor Works certificate and PAT records on the BS 7671 model forms and turns them into branded PDFs. Photograph the consumer unit and the circuit schedule drafts itself; point the phone camera at a Megger MFT-X1 and the reading goes straight into the schedule of test results, or dictate it while your hands stay on the probes. Suggested observation wording with the regulation reference is there for you to check and confirm. The judgement stays yours; the typing goes. Starter is free for 7 days, then £5 a month.