What is PAT testing?
PAT testing is the inspection and testing of portable electrical appliances to check they are safe to use. The underlying legal duty is to maintain electrical equipment safely, not to test it at a fixed interval.
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<a href="https://facilityoptix.co.uk/glossary/pat-testing">What is PAT testing?</a> — diagram by
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</figure>The regulations require maintenance rather than testing specifically, which is a distinction that changes how the work should be planned. Testing is one way of discharging the duty, and for some equipment a visual inspection is a more proportionate one.
Frequency is risk-based. A power tool on a construction site and a desk lamp in an office carry very different risks and do not warrant the same regime, though they are routinely given one.
The most valuable part is often the user check, which costs nothing and catches the damage that actually causes incidents — cracked plugs, damaged flexes, equipment used in conditions it was not intended for.
In practice
A building where every appliance carries a label.
The labels are current and the kettle in the third floor kitchen has a frayed lead that the user can see and the label cannot.
Inspection and testing of portable equipment is risk-based, and user checks are the part that finds damage between visits because damage happens between visits.
A labelling programme can create confidence that displaces the check that would actually work.
What goes wrong in practice
- Everything tested annually regardless of risk, which costs money and still misses damage occurring between tests.
- Labels applied without a record, so the register exists only as stickers on equipment.
- New equipment entering the building outside the regime entirely.
- User checks never established, leaving all detection to an annual visit.