EICR Codes Explained: What C1, C2, C3 & FI Mean for UK Electricians

right so youre doing EICRs and need to actually understand what these bloody codes mean

not the BS 7671 waffle - the real shit that matters when youre filling out the cert at 4pm on a friday

heres everything about C1, C2, C3 and FI codes without the nonsense

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What Are EICR Observation Codes?

when youre doing an electrical installation condition report youre checking the fixed electrics against BS 7671 current regs

anything dodgy gets written down as an "observation" and you slap a code on it - C1, C2, C3 or FI

the code tells everyone how serious it is - from "get out the house now" to "yeah fix it eventually maybe"

the main guide for this is Best Practice Guide 4 from Electrical Safety First. its what everyones supposed to use so the codes actually mean the same thing whether youre in leeds or london

basically its the cheat sheet that stops one spark calling everything C2 while another marks the same thing C3

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Code C1: Danger Present

what it means

immediate risk of injury or fire right now

not "could be dangerous" - dangerous today, this minute

examples you actually see

• exposed live wires someone can touch (damaged cables with copper showing)
• consumer unit covers missing so you can see live busbars
• severe scorching or overheating at connections
• main earthing completely disconnected or just not there

what you do

fix it before you leave site

yeah seriously - youre not supposed to just write C1 on the cert and walk away. isolate it, lock it off, make it safe

landlord side

property is unsafe full stop

tenants cant use those circuits and the landlord needs emergency repairs done before its compliant again

no grey area on C1s

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Code C2: Potentially Dangerous

what it means

not dangerous right this second but could become serious if a fault develops or things change

needs fixing urgently but you dont have to down tools immediately

examples you see all the time

• no RCD protection on sockets used outdoors
• insulation deteriorated so you can see copper conductors
• wrong rated protective devices (someone stuck a 32A breaker on 2.5mm cable)
• missing supplementary bonding in bathrooms where its required

what you do

urgent remedial work needed

the installation is unsafe until its sorted

the 28 day rule

landlords have maximum 28 days from inspection date to fix C2 faults under the private rented sector regs

or sooner if you write a shorter timeframe on the cert

this ones actually law not a suggestion

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Code C3: Improvement Recommended

what it means

doesnt meet current best practice but its not actually dangerous

usually means it was compliant when it was installed but regs have moved on

common examples

• older plastic consumer unit in good nick (regs prefer metal now)
• no surge protection devices
• missing circuit labels on the board
• old wiring colours (red/black instead of brown/blue)

what you do

nothing if you dont want to

its advisory only - improvement recommended to make it better but not mandatory

why C3 doesnt fail the EICR

because theres no danger present or potential

you can have 47 C3 codes and still get a satisfactory outcome

landlords dont legally need to fix C3s to rent the property out

obviously fixing them is good practice and future-proofs the installation but its not required for compliance

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Code FI: Further Investigation Required

what it means

found something that looks dodgy but cant properly assess the risk without more time, access or testing

examples

• untraced circuits you cant identify
• areas you cant access where you suspect damage
• something that needs specialist testing you dont have kit for

what you do

additional investigation required without delay

needs doing to work out if its actually a C1 or C2 hiding in there

landlords get 28 days to sort the investigation same as C2s

treat FI like C2 for urgency

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What Makes an EICR Unsatisfactory?

the pass/fail logic is dead simple:

any C1 = unsatisfactory (fail)

any C2 = unsatisfactory (fail)

any FI = unsatisfactory (fail) until resolved

C3 only = satisfactory (pass)

one C2 on the whole cert? fail

fifteen C3s? pass

thats it

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Common C1/C2/C3 Examples Table

heres what you actually see on sites and what code they get:

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How to Write Professional Observations

right this is where most sparks fall down

youre doing the testing, taking rough notes - "broken plug", "fuse box knackered", whatever

but if those rough notes go straight on the EICR it looks shit to the client and wont hold up legally if challenged

example transformation

rough note: "broken socket in living room"

professional wording: "damage to the casing of the double socket-outlet in the living room, resulting in access to live parts (C1)"

see the difference?

you need to reference BS 7671 language and Best Practice Guide 4 properly

problem is no ones got time to memorize the exact phrasing for 50 different observations

turns out theres tools for this now

TestFast Observation Builder does the translation for you - you put in your quick site notes and it converts them to proper BS 7671 compliant observations without you having to think about it

not saying you need it but if youre doing 3+ EICRs a week and sick of rewriting observations at 6pm it saves the hassle

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Quick Summary

C1 = danger present, fix immediately before leaving site

C2 = potentially dangerous, urgent fix needed (28 days max for landlords)

C3 = improvement recommended, advisory only, doesnt fail the EICR

FI = further investigation required, treat like C2 for urgency

unsatisfactory EICR = any C1, C2 or FI present

satisfactory EICR = C3 codes only (or nothing at all)

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questions people actually ask

what does C1 C2 and C3 mean on an electrical inspection?

theyre observation codes for classifying how serious electrical defects are. C1 is danger present (immediate risk), C2 is potentially dangerous (needs urgent fix), C3 is improvement recommended (advisory only)

what is the code C1 C2 C3?

these codes come from BS 7671 and help landlords and property owners understand electrical safety and prioritize repairs. C1 most serious down to C3 least serious

is a C3 a fail on an EICR?

no. C3 means improvement recommended. if your report only has C3 codes the overall result is satisfactory (pass)

what makes an EICR unsatisfactory?

any C1, C2 or FI codes make it unsatisfactory (fail). C3 codes only = satisfactory

how long do you have to fix a C2?

landlords get maximum 28 days from inspection date under private rented sector regs. or sooner if you specify shorter on the cert

can you ignore C3 codes?

legally yeah. landlords and homeowners arent required to fix C3s to get satisfactory EICR. but fixing them brings property up to current standards which is good practice

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thats it - everything you need to know about EICR codes without the waffle

if youre still writing observations by hand and want to speed it up check TestFast but no pressure