Fixed wire testing: what the law actually asks for.

What it covers, and what it does not.

Fixed wire means everything permanently connected: the incoming supply and main switchgear, distribution boards, submains, final circuits, socket outlets, lighting, isolators and hard-wired plant. It does not cover the things people plug in, which is portable appliance testing and a separate record. What you get back is an Electrical Installation Condition Report: a schedule of inspections, a schedule of test results, observations coded by severity, and a verdict of satisfactory or unsatisfactory. Fixed wire testing, hard wire testing, periodic inspection and commercial EICR are four names for the same job, so if your insurer asks for one and your contractor quotes for another, they mean the same report.

Where the duty comes from.

• The Electricity at Work Regulations 1989. Regulation 4(2) says that as may be necessary to prevent danger, all systems shall be maintained so as to prevent, so far as is reasonably practicable, such danger. The duty sits with the employer and with anyone in control of the premises. You cannot maintain something whose condition you do not know, which is why inspection sits underneath the word maintained.
• The Health and Safety at Work etc. Act 1974 sits above it, with the general duty to provide a safe place of work and safe plant.
• BS 7671, the IET Wiring Regulations, is the technical benchmark, and HSE lists it among the commonly used electrical standards. Not law in itself, but it is what the installation gets measured against by an inspector, an insurer or a court.

The five-year figure quoted at businesses comes from somewhere else. It is in the Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020, which apply to domestic tenancies. If a managing agent has told you there is a five-year legal requirement on your office, they have borrowed a rule from the residential sector. Our plain guide to EICRs covers that domestic side properly.

So how is the interval actually set?

By risk, and it is recorded as a recommendation on the last report. What moves it is the type and use of the premises, the environment the wiring lives in, how often the installation gets altered, who is exposed to it, and whether there is competent supervision on site. A carpeted office untouched for a decade and a production unit washed down every night are not on the same cycle, and treating them as if they are is how a compliance file ends up looking tidy and meaning nothing.

The frequency tables that fill the search results come from industry guidance, mainly IET Guidance Note 3 and Electrical Safety First guidance, and they give maximum intervals to be shortened where conditions call for it. They are the start of a judgement, not a schedule you can point at afterwards. On a mixed site the better answer is often a shorter interval on the parts that take the punishment, with the quiet office areas left on a longer cycle.

What the visit involves.

• Establishing the extent first. How many boards, how many circuits, what is safe to isolate and when. A quote written without this is a guess, and it is why so many commercial inspections overrun.
• Dead tests, then live tests, circuit by circuit. Power is only off where the work is happening, which is how a shop or an office stays open around it.
• Sampling, on anything large. Testing a proportion of circuits and rotating the sample across the cycle is normal and accepted. What matters is that the report states what was tested and what was not.
• Coding and issue. C1 for danger present, C2 for potentially dangerous, C3 for improvement recommended, FI where something needs further investigation, plus a recommended date for the next inspection.

When it comes back unsatisfactory.

Unsatisfactory means at least one C1 or C2 was found. It is a coded list rather than a bill, and it belongs to you, not to the contractor who produced it. C1 items should have been made safe before anyone left the building. C2 items need doing promptly and the installation stays unsatisfactory until they are. C3 goes into the planned maintenance budget, and FI needs investigating before the report can be relied on.

Ask for remedials priced line by line against the report rather than as one figure. What drives that price is how many circuits are affected, whether the work can run alongside a live building or needs a planned shutdown, whether access is out of hours, and how much has to be opened up to reach the cable. Split out that way, you can see which findings are cheap to clear now and which are genuinely a project.

Where it sits alongside everything else.

Buildings routinely have one compliance regime in good order and the others drifting. Emergency lighting has its own testing regime under a different piece of law, fire detection has another, and portable appliances another again. If the premises have been altered recently, the fit out checklist covers what should have been handed over at the end of that work, because missing certification from an alteration is one of the most common findings on the next inspection.

We carry out commercial testing and inspection across Buckinghamshire, Bedfordshire, Hertfordshire and Northamptonshire, and nationwide on larger packages, with remedials priced by the team that found them.

Sources: The Electricity at Work Regulations 1989, regulation 4; HSE: electrical safety frequently asked questions; HSE: electrical standards and approved codes of practice; IET: BS 7671 Wiring Regulations; Electrical Safety First: BS 7671 technical guidance; The Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020.

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