EICR Explained: What a Fixed Wire Test Actually Involves and What Happens Afterwards

TL;DR

• An EICR (Electrical Installation Condition Report) is a formal inspection and test of all fixed electrical wiring and components within a building

• The test is carried out circuit by circuit, covering consumer units, wiring, accessories, and protective devices

• Most commercial premises require an EICR every 5 years, though some settings require more frequent testing

• Results are graded using condition codes (C1, C2, C3, and FI), each with different action requirements

• A satisfactory EICR means no urgent action is needed; an unsatisfactory result requires prompt remedial work

Introduction

If you manage a commercial building, a school, a healthcare facility, or any workplace where people are present, you are likely required by law to maintain a valid EICR. Yet many facilities managers and duty holders have seen the certificate without fully understanding what the engineer actually checked, and what the outcome genuinely means for their compliance position.

This guide explains the fixed wire testing process from start to finish: what the engineer does on site, what the EICR certificate contains, and exactly what you need to do once you have the results in hand.

Whether your EICR is due, you have recently received a result, or you are planning ahead for a multi-site testing programme, this is the article to read first. To arrange a test for your premises, visit our fixed wire testing service page.

What Is an EICR?

An EICR, or Electrical Installation Condition Report, is an official document produced following a thorough inspection and testing of a building's fixed electrical installation. Fixed electrical installation refers to everything that is permanently wired into the building: consumer units (fuse boards), distribution boards, cables running through walls, floors and ceilings, sockets, switches, light fittings, and all the protective devices that keep the system safe.

The EICR is not a test of portable appliances (that falls under separate PAT testing), nor is it a general health and safety audit. It is specifically focused on whether the fixed wiring in the building is safe to use, meets the relevant edition of BS 7671 (the IET Wiring Regulations), and is in satisfactory condition for continued use.

Who Can Carry Out a Fixed Wire Test?

A fixed wire test must be carried out by a competent, qualified electrician. In practice, this means an engineer who holds the relevant inspection and testing qualifications and is either registered with a recognised competent persons scheme (such as NICEIC or NAPIT) or working under the supervision of someone who is.

The engineer takes on personal responsibility for the accuracy of the report. The duty holder, typically the building owner, employer, or facilities manager, takes on legal responsibility for acting on the results.

What Happens Before the Test Starts

Before any circuits are tested, there is a preparation stage that is often underestimated.

The engineer will request access to all electrical distribution boards and consumer units across the building. For larger or more complex sites, a site plan or single-line diagram is useful, though not always required.

The engineer will also carry out a visual inspection before any instruments are connected. This involves checking for obvious signs of damage, overheating, incorrect circuit protection, non-standard wiring arrangements, and any modifications that have been made since the last EICR. Visual inspection findings can themselves generate condition codes.

If the test is a periodic re-inspection rather than the first EICR for a newly occupied building, the engineer will request the previous EICR so that known issues can be tracked and new deterioration identified.

What the Engineer Actually Checks: Circuit by Circuit

The testing process is methodical and circuit-specific. Each circuit in the building is individually identified, isolated, and tested. The number of circuits varies enormously depending on building size, but a typical commercial property might have anywhere from 20 to several hundred individual circuits.

Dead Testing

Dead testing takes place with circuits de-energised (switched off or isolated). This stage includes:

Continuity testing verifies that the protective earth conductors running through the circuit are intact and functioning. A broken earth conductor is a serious fault because it removes the protection that prevents electric shock in the event of a fault.

Insulation resistance testing checks the integrity of the insulation around conductors. Aged, damaged, or contaminated insulation can break down and allow current to flow where it should not, creating shock and fire risks.

Polarity testing confirms that all live, neutral, and earth conductors are connected correctly throughout the circuit, including at every socket, switch, and fitting.

Live Testing

Once dead tests are complete and circuits are re-energised, the engineer moves to live tests.

Earth fault loop impedance testing measures the total resistance of the fault current path, confirming that in the event of a fault, protective devices will disconnect the circuit fast enough to prevent injury.

RCD testing verifies that residual current devices operate within the required disconnection times. An RCD that fails to trip within the correct timeframe provides no meaningful protection. You can read more about how RCDs are tested as part of routine compliance testing on the RCD testing page.

Prospective fault current measurement records the maximum short-circuit current available at the distribution board, confirming that installed protection devices are rated to handle it.

Thermal Imaging (Optional but Recommended)

For larger or higher-risk installations, thermal imaging surveys can be carried out alongside or after the fixed wire test. Thermal imaging detects heat signatures in energised panels and connections that indicate loose connections, overloaded circuits, or components in the early stages of failure, before they show up as formal EICR faults.

How Long Does a Fixed Wire Test Take?

The duration depends primarily on the number of circuits and the physical complexity of the site. A small commercial unit with a single consumer unit might take four to six hours. A multi-floor office building, a school campus, or an NHS facility can take several days or require a rolling programme of visits.

Planned access windows are important. Most tests require circuits to be de-energised in sequence, which means some areas of the building will lose power temporarily during testing. Good coordination between the engineer and the facilities team keeps disruption to a minimum.

Understanding Your EICR Certificate

Once testing is complete, the engineer produces the EICR certificate. This is a standardised document following the format set out in BS 7671. It includes:

• The property address and details of the installation

• The date of the inspection and the identity of the inspector

• The extent of the installation covered (and any areas excluded from the inspection)

• A list of all circuits tested with their associated test results

• Observations listed by condition code

• An overall verdict: satisfactory or unsatisfactory

The observations section is where the practical meaning of your EICR lies. Each observation is assigned one of four condition codes.

EICR Condition Codes Explained

Understanding condition codes is essential for any duty holder who receives an EICR. For a detailed breakdown of each code with commercial examples, see the article on EICR failures explained: C1, C2, and FI codes.

C1: Danger Present

A C1 code indicates an immediate danger. The risk of injury or death is present in the current state of the installation. A C1 finding must be made safe immediately, and in some cases the engineer will advise that the circuit should not be re-energised until the fault is rectified.

C2: Potentially Dangerous

A C2 code indicates a potentially dangerous condition. The installation is not currently causing harm, but there is a risk that it could. C2 faults must be remedied urgently, and any EICR containing a C2 or above is classified as unsatisfactory overall.

C3: Improvement Recommended

A C3 code does not make the EICR unsatisfactory. It records that an improvement would enhance safety but is not a current or potential danger. C3 items should be kept under review and addressed over time, particularly ahead of the next EICR.

FI: Further Investigation Required

An FI code means that the engineer encountered something during testing that warrants further investigation before a definitive assessment can be made. It does not automatically make the EICR unsatisfactory, but it does require follow-up. Ignoring an FI finding is not acceptable.

What Happens After the Test: Satisfactory Result

If your EICR comes back satisfactory, it means no C1 or C2 faults were found. The installation is considered safe for continued use until the next scheduled inspection.

Your next steps are straightforward: file the certificate securely (you may be asked to produce it by insurers, auditors, landlords, or enforcement bodies), and note the recommended date for the next inspection in your compliance calendar.

Any C3 observations should be documented and reviewed. While they do not require immediate action, addressing them proactively reduces the likelihood of them becoming C2 issues by the time of your next EICR.

What Happens After the Test: Unsatisfactory Result

An unsatisfactory EICR means one or more C1 or C2 faults have been identified. The practical and legal consequences are significant.

For C1 faults, the risk is immediate. The affected circuit or installation area should be made safe without delay. This may mean switching off a circuit until it is repaired. The electrical remedial repairs process begins immediately.

For C2 faults, urgency is still required, though the timescale is not necessarily the same day. There is no defined regulatory deadline in days for C2 remedials in most commercial settings; the expectation is that faults are addressed promptly and that the duty holder can demonstrate they are taking action.

The EICR does not expire when faults are found. It remains the record of inspection. Once all remedial works are completed, the engineer who carries out the remedials should issue documentation confirming that faults have been rectified. In some cases, a new EICR or a minor works certificate is issued following remediation.

For a full breakdown of the remedial works process, see the EICR remedial works guide for duty holders.

How Often Do You Need a Fixed Wire Test?

Testing frequency under BS 7671 depends on the type of premises. For full details of your electrical services compliance obligations, these should be reviewed in the context of your specific lease, insurance policy, and sector. Standard recommended intervals include:

• Commercial offices: every 5 years

• Retail premises: every 5 years

• Schools and educational buildings: every 5 years

• Healthcare premises: every 5 years (some higher-risk areas annually)

• Hotels and guest accommodation: every 5 years

• Industrial premises: every 3 years

• Temporary installations: every 3 months

Insurers and landlords may require more frequent testing than the maximum recommended interval. Always check your lease, policy, and sector guidance before setting your compliance schedule.

Frequently Asked Questions

What is the difference between an EICR and a fixed wire test?

There is no practical difference. Fixed wire testing is the process; an EICR is the document that results from it. The two terms are used interchangeably across the industry, and both refer to the same inspection and testing of a building's permanent electrical installation.

Does a fixed wire test require power to be switched off?

Yes, during certain stages. Dead testing requires circuits to be isolated so that insulation resistance and continuity tests can be carried out safely and accurately. However, circuits are re-energised for live testing. A good engineer will minimise disruption by planning the testing sequence carefully with the site team.

Can I use my building during a fixed wire test?

In most cases, yes, with some temporary disruptions. Areas of the building may need to be without power while specific circuits are tested. For larger sites, testing is often planned in phases or out of hours to avoid operational impact.

What happens if my EICR is unsatisfactory?

If your EICR is classified as unsatisfactory due to a C1 or C2 observation, you are required to address the faults. C1 faults must be made safe immediately. C2 faults must be remediated urgently. Once the remedial work is complete, the appropriate certification should be issued. You do not automatically need a full re-test once remedials are done, but you should ensure the corrective work is documented.

How long is an EICR valid for?

The EICR is valid until the next recommended inspection date, which is stated on the certificate itself. For most commercial premises this is five years, though some sectors and some insurers specify shorter intervals. The certificate does not become invalid because faults were found; it remains the inspection record regardless.

Who is responsible for ensuring a building has a valid EICR?

The duty holder is responsible. In a commercial setting this is typically the building owner, landlord, or employer depending on the terms of the lease and the nature of the occupation. Facilities managers often carry operational responsibility for compliance, but the legal obligation sits with the duty holder.

Can the same contractor carry out the EICR and the remedial works?

Yes, in most circumstances. There is no regulatory prohibition on the same contractor testing and then carrying out remedial work. What matters is that the engineer carrying out the inspection is competent and independent in their assessment. Using the same company for both testing and remedials is common and can be more efficient for site coordination.