There is no single PAT testing interval that applies to every appliance in every workplace. The right frequency depends on the type of electrical equipment, how it is used, the environment it is used in and what previous checks have found.

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Is annual PAT testing required?

No blanket rule says every portable appliance must be PAT tested once a year. HSE guidance explains that the law requires electrical equipment to be maintained so that it does not present danger, but it does not prescribe one fixed inspection or testing interval for every item.

For some higher-risk equipment, more frequent checks may be sensible. For low-risk office equipment that remains stationary and shows a good history of safe use, formal testing may be needed much less often.

What affects the testing frequency?

• How often the equipment is moved: equipment that is regularly unplugged, transported or handled is more likely to suffer cable, plug or casing damage.
• The environment: dust, moisture, impact, heat and rough handling can increase the chance of deterioration.
• The type of equipment: portable tools and extension equipment can present a different risk profile from a desktop monitor.
• Previous results: repeated faults are a good reason to review and potentially shorten the inspection interval.
• User checks: trained staff noticing damage between formal inspections can be an important part of the maintenance programme.

Examples of different environments

An office may contain mainly stationary computers, monitors and printers. A construction site or maintenance workshop may use portable tools and leads that are moved constantly and exposed to tougher conditions. It would not make sense to apply exactly the same testing interval to both environments.

Our sector pages explain how this can vary for offices, schools, manufacturing and warehouses, and construction equipment.

How should a business decide?

A sensible approach is to review the equipment, how it is used, the environment and previous test history. Formal visual inspection and electrical testing can then be scheduled where it adds value to the maintenance programme.

HSE provides useful guidance on this risk-based approach in its portable appliance testing FAQs and guidance on maintaining electrical equipment safely.

Need help setting up a PAT testing programme?

National PAT Compliance provides professional PAT testing for businesses, landlords and organisations across the UK. We can help structure a practical programme around your equipment and operating environment.

Request a PAT testing quote or explore the areas we cover.