PAT TESTING · SCOPE

PAT Testing Equipment: What Needs to Be Tested?

PAT testing is often assumed to cover everything electrical in a building. It does not. It covers a specific category - portable and movable equipment that plugs in - and knowing where that line sits saves both missed items and wasted effort.

PAT testing equipment is any portable or movable electrical item that connects to the mains by a plug and socket, from kettles, computers and extension leads to power tools and floor cleaners. It applies to both earthed (Class I) and double-insulated (Class II) appliances. Fixed wiring and permanently connected equipment are not PAT tested; they are covered by periodic inspection of the electrical installation instead.

What counts as portable or movable equipment for PAT testing

The simple test is the plug: if a piece of equipment connects to the supply through a plug and socket and can be moved, it is in scope. That includes handheld tools, desktop appliances, floor-standing equipment on castors, and the leads and extension blocks that power them. It also includes equipment that is rarely moved but still plugged in, such as a desktop PC or a fridge.

Class I and Class II

PAT testing covers both protection classes, though the tests differ slightly:

Common PAT testing equipment

• Kettles, microwaves, toasters and other kitchen appliances
• Computers, monitors, printers and chargers
• Extension leads, RCD adaptors and multi-socket blocks
• Power tools, both mains-powered tools and battery chargers
• Vacuum cleaners, floor scrubbers and other cleaning equipment
• Portable heaters, fans and desk lamps

The equipment used to carry out PAT testing

PAT testing is carried out with a calibrated PAT tester, alongside a visual inspection of each item's plug, cable and casing. The tester checks earth continuity on Class I items and insulation resistance on both classes. Where needed, it also measures leakage current and checks the polarity of extension leads. Each result is logged against the item, and a pass or fail label is applied so the next test date is visible on the equipment itself.

Types of PAT testing equipment

• Pass/fail testers: simple handheld units that give a pass or fail result, with limited detail.
• Manual PAT testers: show full readings for earth continuity and insulation resistance, so the tester can judge each result.
• Automatic PAT testers: run a full sequence of tests and store the results, often with labels and software for an asset register.
• Insulation and earth testers: used alongside PAT testers for more detailed electrical checks.

What is not PAT tested

The building's fixed electrical installation - socket outlets, distribution boards, hard-wired equipment and the wiring itself - is not PAT tested. It is covered instead by periodic inspection and testing of the installation, a separate exercise carried out by a registered electrician. Confusing the two is common, so it is worth being clear: PAT is for the things that plug in; periodic inspection is for what they plug into.

Should you buy PAT testing equipment or use a service?

Buying PAT testing equipment can seem cheaper, but the tester is only part of the cost.

For most businesses, a professional service is simpler. Arkomax brings calibrated PAT testing equipment to your site, tests and labels every item, and provides a full report for your records.

Frequently asked questions

• What equipment needs PAT testing?

  Any portable or movable electrical equipment that connects to the mains through a plug and socket needs PAT testing. That includes Class I earthed and Class II double-insulated appliances, IT equipment, kitchen appliances, power tools, cleaning equipment, chargers and extension leads.
• Do extension leads need PAT testing?

  Yes. Extension leads, multi-socket blocks and RCD adaptors take heavy wear and are among the items that fail most often, so they should be included in every PAT testing schedule.
• Does new equipment need PAT testing?

  New equipment should be safe as supplied by the manufacturer, so it does not usually need a full test before first use. It should still be visually checked and added to the asset register so it is included in the next routine PAT test.
• Do battery-powered tools need PAT testing?

  The battery-powered tool itself does not, because it never connects to the mains. The charger does, because it plugs into a socket, so chargers are tested as portable equipment.
• Is hard-wired equipment PAT tested?

  No. Equipment permanently connected to the supply, such as hand dryers, fixed heaters and appliances on a fused spur, forms part of the fixed installation and is covered by periodic inspection and testing by a registered electrician.
• What equipment is used to carry out PAT testing?

  PAT testing is carried out with a calibrated PAT tester that measures earth continuity, insulation resistance and, where needed, leakage current and lead polarity, alongside a visual inspection. Each result is recorded against the item and a pass or fail label is applied.
• Should I buy PAT testing equipment or use a PAT testing service?

  Buying PAT testing equipment means paying for the tester, regular calibration, training and record-keeping software, and the person testing must be competent to do it. For most businesses, a professional PAT testing service is simpler: the technician brings calibrated equipment, tests and labels every item, and provides a full report for your records.