PAT Testing: What It Is, Who Needs It, How Often — and What It Costs in 2026

What Is PAT Testing?

PAT stands for Portable Appliance Testing — the inspection and electrical testing of moveable electrical equipment. The “portable” in the name is slightly misleading: it covers everything from a laptop charger to a floor-standing photocopier, as long as it has a plug and cable and is not a fixed installation.

A PAT test has two stages. First, a visual inspection: checking the plug for signs of damage, burns, or incorrect wiring; examining the cable for cuts, fraying, or joints; and looking at the appliance body for damage that could expose live parts. Second, instrument testing using a dedicated PAT tester: earth continuity (resistance from the earth pin to the appliance casing), insulation resistance (confirming no breakdown between live conductors and earth), and for some equipment, earth leakage current.

Equipment that passes receives a dated PASS label. Equipment that fails is removed from service immediately and either repaired or scrapped. A written register of all tested items, results, and due dates is provided.

Is PAT Testing a Legal Requirement?

There is no legislation that uses the words “PAT testing” or prescribes how often it must be done. What the law does require:

• Health and Safety at Work Act 1974: employers must ensure the health, safety and welfare of employees so far as is reasonably practicable. Faulty electrical equipment is a foreseeable hazard.
• Electricity at Work Regulations 1989, Regulation 4: all electrical systems (including portable appliances) shall be maintained so as to prevent danger. There is no specific test frequency, but “maintained” implies inspection at reasonable intervals.
• Provision and Use of Work Equipment Regulations 1998 (PUWER): work equipment must be maintained in an efficient state. Portable appliances are work equipment.

PAT testing, with its documented results, is the accepted method of demonstrating compliance with these duties. Insurers increasingly require it, and HSE inspectors treat absence of records as a risk indicator. For rental properties, the Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020 require an EICR every 5 years — PAT testing of white goods and portable appliances in furnished lettings is additional good practice but not a statutory requirement under that regulation (though HMO licences may include a PAT condition).

How Often Does PAT Testing Need to Happen?

The IET Code of Practice for In-Service Inspection and Testing of Electrical Equipment (5th edition) recommends risk-based intervals. The table below summarises the guidance:

Annual testing is the most common approach and satisfies the majority of insurers without needing to justify a risk assessment for every item. If your insurer has a specific requirement, that takes precedence.

What Happens During a PAT Test

When DS Electrical carries out PAT testing on your site:

1. Inventory log: every item is recorded — description, asset number or serial, location. This becomes your appliance register.
2. Visual inspection: plug, cable, and appliance body checked for damage, loose parts, or modifications. Many failures are caught here without instrument testing.
3. Instrument tests: earth continuity and insulation resistance measured using a calibrated PAT tester. Class I appliances (earthed) get both tests; Class II (double-insulated, no earth) get insulation resistance only.
4. Labelling: PASS items get a dated label showing the test date and recommended retest date. FAIL items are labelled DO NOT USE and removed from service.
5. Written register: a full report listing all items, test results, and any recommendations. This is your evidence of compliance.

Testing typically takes 2–5 minutes per item depending on appliance complexity and accessibility. A 30-item office can usually be completed within half a day.

PAT Testing Costs in Somerset 2026

Pricing depends on the number of items, the types of appliance, and site access (a multi-storey building takes longer than a single-floor office). Typical Somerset rates:

All prices indicative. Actual cost depends on number of items, appliance types, and site conditions. VAT at 20% applicable.

What Can Fail a PAT Test?

Common causes of PAT test failure:

• Damaged or frayed cable — especially near the plug or where the cable enters the appliance
• Incorrect fuse rating in the plug (a 13A fuse on a desk lamp that should be 3A)
• Cable joints or DIY repairs using connector blocks
• Cracked or broken plug casing exposing live pins
• Earth continuity failure — earth wire not connected inside the plug or appliance
• Insulation breakdown — often caused by age, heat damage, or liquid ingress
• Extension leads overloaded or used as a permanent installation

PAT Testing vs EICR: What's the Difference?

These are two separate obligations that are frequently confused:

You need both. An EICR passing does not imply the kettle in the kitchen is safe, and a PASS label on a microwave tells you nothing about the wiring behind the sockets it plugs into.

Frequently Asked Questions