EICR Code C1: Danger Present
C1 is the most serious EICR observation code. It means danger is present, there is a risk of injury, and immediate remedial action is required — often before you leave the property.
When you carry out an Electrical Installation Condition Report (EICR) to BS 7671, every observation you record is classified with a code that tells the client how urgent it is. A Code C1 sits at the top of that scale: it means someone is at immediate risk and the installation cannot be left as it is.
This guide explains exactly what a C1 means, how it differs from C2 and C3, the kinds of defect that warrant one, and the steps you must take on site once you find one.
Key takeaways
- C1 means "danger present, risk of injury" — the most serious EICR classification.
- A single C1 makes the overall EICR outcome unsatisfactory.
- You should make safe or isolate the danger before leaving site, with the client’s agreement.
- Record the defect, the code, and the action taken clearly on the report.
- Typical C1s include exposed live parts, accessible conductors, and incorrect polarity on a live circuit.
What a C1 means
Code C1 is defined in BS 7671 and IET Guidance Note 3 as "Danger present. Risk of injury. Immediate remedial action required." It is used when a condition on the installation could cause injury to a person or livestock without any further fault developing — the danger already exists at the time of inspection.
Because the risk is immediate, a C1 cannot wait for a quote to be approved or for the next visit. The expectation is that the danger is removed, isolated, or made safe there and then.
The test for a C1
Ask: is there a real, present risk of injury right now, before anything else fails? If yes, it is a C1 — not a C2.
C1 vs C2 vs C3
The difference between the codes is about when the danger occurs. A C1 is dangerous now. A C2 (potentially dangerous) becomes dangerous only if a further event happens — for example a fault, a failure, or someone touching a part that is not normally live. A C3 (improvement recommended) is not dangerous at all; it simply falls short of the current standard.
Getting this distinction right matters: a C1 or C2 makes the report unsatisfactory, whereas C3 observations on their own leave it satisfactory.
Real-world C1 examples
Common conditions that warrant a C1 include: exposed live conductors or accessible live parts, a broken or missing consumer unit cover leaving busbars accessible, incorrect polarity on a live final circuit, conductive parts made live by a wiring fault, and damaged accessories where live parts can be touched.
Other examples include a missing or disconnected main protective bonding where a genuine, immediate shock risk exists, and signs of thermal damage or arcing at a live connection.
How to record and act on a C1
On the report, describe the defect precisely, give it the C1 classification, and note the action you took — for example "made safe by isolation" or "cover refitted". The overall assessment box must then be marked unsatisfactory.
Practically, you should make the danger safe before leaving, with the duty holder’s agreement, and explain clearly what was found and what remedial work is needed. If the client refuses to allow the danger to be made safe, record that too.
Issue it on site
TradePlanr lets you fill and sign an EICR on your phone, code each observation, and hand over a proper PDF before you leave — no writing it up back at the office.
Frequently asked questions
Does one C1 fail an EICR?
Yes. A single C1 (or C2) means the overall condition of the installation is reported as unsatisfactory.
Do I have to fix a C1 on the spot?
You are expected to make the danger safe — by isolation, removal or repair — before you leave, with the client’s agreement. Full remedial work can follow, but the immediate danger must not be left live.
What if the client won’t let me make it safe?
Record the C1, record that permission to make safe was refused, and make sure the duty holder understands the risk in writing. Your report should reflect exactly what you found and what happened.
From guidance to action
Related guides
EICR Code C2: Potentially Dangerous
When to code C2, how it differs from C1 and C3, and why it makes an EICR unsatisfactory.
EICR Code C3: Improvement Recommended
What C3 covers, why it does not fail an EICR, and common examples you can code C3.
Initial Verification: The BS 7671 Testing Sequence
The correct dead-then-live testing sequence for initial verification, step by step.
