Will fixed wire testing disrupt your business?
Expect some power interruptions during fixed wire testing. Whether your business can stay open depends on the installation, the tests required and what the affected circuits supply. Agree the inspection scope and shutdown arrangements before booking; an evening appointment or a promise to work in sections does not, by itself, settle those questions.
Start with what your business needs to keep running
Give the contractor a list of operations that cannot tolerate an unexpected interruption. That might include payment terminals, servers, refrigeration, access controls or production equipment. Name the person responsible for each system and explain the consequences of it stopping. Include known backup supplies or generation so the contractor can assess them; do not assume a battery or generator makes an interruption harmless.
This is information for the competent contractor to plan the work. It is not a request for your staff to identify live conductors, open electrical equipment or carry out isolation. HSE's electrical safety guidance says installations should be inspected and tested by someone competent, and that live work is only justified in limited circumstances. Keeping the business convenient to operate is not a safety plan.
Can testing be split into areas or done outside opening hours?
Ask the contractor to assess both options. Working in stages may reduce disruption where the installation allows it, but a room name is not proof of an independent electrical supply. An out-of-hours visit still needs authorised access, someone to manage affected equipment and a plan for returning the premises to use.
For example, a shop might be able to close one sales area, yet its payment system may depend on network equipment elsewhere. This is an illustrative dependency, not a Crest case study. Tell the contractor and your IT provider what must remain available rather than promising staff that only one room will be affected.
Ask for the proposed interruptions to be described by affected operation as well as electrical circuit. Duration and sequencing need a site-specific assessment; there is no useful universal downtime promise for every office, shop or workshop.
A booking brief your facilities team can use
Prepare the following information before requesting a confirmed programme. If something is unknown, mark it as unknown and ask how it will be established.
- Premises and scope: address, occupied areas, landlord or tenant boundaries, and the previous EICR and available circuit records.
- Access: who can admit the contractor, unlock relevant rooms and arrange access with other occupants.
- Operational dependencies: equipment that must be shut down in a controlled way, specialist support contacts and any known backup supplies.
- Acceptable windows: proposed dates, trading or production constraints, and who can approve a change to the programme.
- Restart: who checks business systems afterwards and confirms they are ready for use, separately from the electrician's electrical checks.
- Contingency: who receives urgent findings, who can authorise necessary work and how an affected area will be managed if it cannot be returned to service as expected.
This is a coordination worksheet, not an isolation method or a substitute for the contractor's assessment. Keep the electrical safety decisions with the competent people doing the work.
What if a circuit cannot be switched off on the day?
Raise that constraint before the visit. Ask what inspection and testing can be completed, what would remain outside the agreed scope, and whether another visit or operational change is needed. Do not treat an omitted test as a successful test.
The IET's explanation of EICR extent and limitations distinguishes limitations agreed before work from operational limitations encountered during it. The report should make clear what was and was not inspected and tested. Use those details to understand coverage rather than reading only the overall result.
If an access problem or critical load remains unresolved, ask what the report can meaningfully establish and what follow-up is recommended. The aim is a useful assessment of the installation, not simply a document obtained with the fewest interruptions.
Compare the programme as well as the price
Ask each contractor to quote against the same scope and access assumptions. Clarify whether the price includes agreed out-of-hours attendance, reporting, additional access visits and any specialist coordination. Ask how remedial work would be authorised and priced if needed; do not assume it is included in the inspection fee.
Our commercial fixed wire testing guide explains the purpose of the assessment. This visit-planning guide helps you supply the information needed to arrange it. If you are also planning alterations, the office and shop electrical checklist covers questions to raise before committing to premises.
Discuss a testing visit with Crest
Crest Electrical Contractors handles commercial testing and inspection enquiries across Buckinghamshire, Bedfordshire, Hertfordshire and Northamptonshire. Send the site address, use of the premises, previous report if available, and your operational constraints. We can discuss the information and assessment needed to plan the visit. Request a commercial testing quote, or read about our testing and inspection service.
Asked about this.
Does booking at night guarantee no disruption?
No. Equipment may still need controlled shutdown and restart, access must be arranged, and the contractor needs to assess what can be tested safely. Agree responsibilities before confirming the appointment.
Should we send the old EICR when asking for a quote?
Yes, if available, together with records of later alterations and known access or operational constraints. Tell the contractor if records are missing; an old report does not establish the present condition on its own.