No — and it must not be. The survey is carried out with the installation energised and under normal operating load. Thermal anomalies only manifest when current is flowing through the connection or component. Isolating the installation removes the very condition that the survey is designed to detect. The only access required is to open distribution board doors, which is carried out safely by our qualified engineers.

A minimum of 40% of normal operating load is generally required for meaningful thermal data. At lower load levels, the temperature differentials at faulty connections may be too small to detect reliably. We confirm load conditions before the survey and, where possible, schedule the survey during a representative operating period for your site.

We classify thermal faults using a temperature differential (Delta T) approach referenced against ambient temperature and similar healthy connections on the same installation. Minor faults (Delta T < 10°C above ambient) are noted as advisory; moderate faults (10–40°C) are classified as recommended actions; significant faults (>40°C) are classified as requiring urgent attention. We note the load conditions at the time of survey alongside every measurement.

Annual thermal imaging is recommended for most commercial and industrial installations, ideally coordinated with the annual PPM inspection. High-risk environments — data centres, continuous process facilities, healthcare, cold storage — may benefit from six-monthly surveys. Following any significant load changes or after identified faults have been remediated, a follow-up survey confirms that the issue has been resolved.

Most insurers that require thermal imaging as a condition of cover will accept a report from an electrically qualified thermographer that includes: survey methodology, load conditions at time of survey, thermographic images with temperature annotations, fault classification and remedial recommendations. Our reports are produced to this standard. If your insurer has a specific report format requirement, let us know at the booking stage and we will confirm whether we can accommodate it.

Category 1 faults — those presenting an immediate risk of failure or fire — are reported to you verbally during the survey visit, before the written report is produced. We will advise on the urgency of remedial action and can arrange emergency electrical works where required. Category 2 and advisory findings are reported in the written report with recommended timescales for remediation.

Yes. Barrow Electrical carries out all electrical remedial works in-house — connection retightening, component replacement, circuit derating or protection device upgrades. Where the remedial work is within the scope of our visit, we will carry it out on the same day where practical and the client agrees. More significant works are quoted separately and scheduled at a convenient time.