PAT testing (Portable Appliance Testing) is the routine inspection and electrical testing of plug-in electrical appliances to ensure they are safe for continued use. The process helps employers, landlords, and business owners prevent electrical shocks, burns, and fires.

The Testing Process

PAT testing generally involves two main components:

1. Formal Visual Inspection: A trained or competent individual checks the appliance body, cable, and plug for obvious defects like cracks, frayed wiring, or scorched casings.
2. Manual Electrical Testing: Specialized testing equipment is used to check for hidden internal issues, such as earth continuity, insulation resistance, and functional current leakage.

Once completed, tested items are typically marked with a pass or fail label, and a full testing report or digital certificate is provided.

What Needs Testing?

Contrary to the word “portable,” the test applies to any electrical equipment powered via a plug and socket. This includes:

• Portable items: Laptops, kettles, power tools, extensions cords, and vacuum cleaners.
• Stationary/Large items: Fridges, washing machines, and vending machines.
• IT equipment: Desktop computers, monitors, and printers.

Legal Requirements in the UK

There is no specific law that explicitly mandates annual PAT testing. However, UK legislation—such as the Health and Safety at Work Act 1974 and the Electricity at Work Regulations 1989—places a strict legal obligation on employers and landlords to maintain electrical equipment in a safe condition to prevent danger.

Because of this, standard PAT testing is widely recognized as the most practical method for proving compliance and showing “due diligence” to local authorities and insurance providers.

How Often is it Required?

The law does not define fixed intervals or strict time limits. Instead, testing frequency should be determined using a risk-based approach, taking into account the type of equipment and the environment in which it is used. For example:

• High-risk environments (e.g., construction sites or industrial workshops) require frequent testing, sometimes every 3 to 6 months.
• Medium-risk environments (e.g., commercial kitchens, schools, or hotels) typically require testing every 12 to 24 months.
• Low-risk environments (e.g., standard offices) may only require formal testing every 2 to 4 years, relying primarily on regular visual checks by staff.