What Is a PAT Test? A Plain-English Guide for UK Businesses

PAT testing gets surrounded by more confusion and misinformation than almost any other workplace compliance topic. Most of that confusion traces back to two things: the belief that it is a strict legal requirement (it is not, in the sense most people mean), and the assumption that all appliances in a workplace need testing on a fixed annual cycle (also not accurate).

This guide covers what PAT testing actually is, what the law actually requires, and what a sensible programme looks like.

What PAT stands for

PAT stands for Portable Appliance Testing. It refers to the formal inspection and testing of electrical appliances that are not a fixed part of a building's electrical installation — so equipment that has a plug, rather than wiring directly into the mains.

Examples of portable appliances: laptops, kettles, desk lamps, extension leads, vacuum cleaners, drills, phone chargers, floor-standing fridges, photocopiers.

What is NOT portable appliance testing: testing of fixed wiring (that is an Electrical Installation Condition Report, or EICR), fixed lighting, or permanently wired equipment like kitchen appliances that are hard-wired.

What a PAT test involves

A full PAT test — formally called "combined inspection and testing" — has two parts:

1. Formal visual inspection. The person carrying out the test examines the appliance for visible damage: cracked or discoloured plugs, frayed or damaged cables, burn marks on connectors, damaged casings, or signs of previous repairs. This check does not require any test equipment and can catch most dangerous faults that are visible to the eye.

2. Electrical testing. Using a specialist PAT tester device, the tester measures the appliance's earth continuity (the connection that protects against shock in a fault condition), insulation resistance (to check that electrical insulation has not broken down), and sometimes leakage current (the amount of current flowing where it should not). The combination of these measurements gives a much more complete picture of the appliance's condition than visual inspection alone.

An appliance that passes both checks gets a pass label. An appliance that fails either check should be removed from service.

Is PAT testing legally required?

This is the question that creates the most confusion.

The law that applies — primarily the Electricity at Work Regulations 1989 (EAWR) and the Provision and Use of Work Equipment Regulations 1998 (PUWER) — does not specifically require PAT testing. Both instruments apply in Great Britain rather than UK-wide: EAWR regulation 31 and PUWER regulation 3(1) each say the Regulations "shall apply— (a) in Great Britain". A Northern Ireland workplace is governed by the Health and Safety at Work (Northern Ireland) Order 1978 and the Electricity at Work Regulations (Northern Ireland) 1991 instead. The HSE's published guidance is clear: "the law simply requires an employer to ensure that their electrical equipment is maintained in order to prevent danger. It does not say how this should be done or how often."

What is required is the outcome: electrical appliances must be maintained in a safe condition. PAT testing is one way to demonstrate that — but it is not the only way, and it is not mandated by name.

In practice, PAT testing is the most commonly used method because it produces an auditable record of specific measurements taken on specific dates. For most employers, that record is the clearest way to demonstrate compliance if an inspector or insurer asks for evidence of maintenance.

For a detailed breakdown of the specific regulations, see the portable appliance testing requirements guide.

How often does PAT testing need to happen?

There is no statutory fixed frequency. The appropriate interval depends on:

The type of appliance
How often it is used
The environment it operates in
Who uses it (trained staff or members of the public)
The history of the appliance (has it failed before? Has it been repaired?)

The IET Code of Practice for In-Service Inspection and Testing of Electrical Equipment (5th edition) — the sector benchmark document — gives frequency recommendations, but these are guidance, not law. An office kettle might need a formal check every two to four years; a power tool used daily on a construction site might need checking every three months.

The PAT testing frequency calculator takes you through the relevant factors for specific appliance types and produces an appropriate interval recommendation.

Who can do PAT testing?

Visual-only inspections can be carried out by any competent and responsible person who has been trained to know what they are looking for — there is no formal qualification requirement for visual inspection alone.

Combined inspection and testing (the full test with equipment) requires a higher level of competence. The IET Code of Practice specifies that the person should have knowledge of the Code, relevant training, and practical experience. The most widely recognised qualification is City & Guilds 2377 (the current award is the 2377-77 Level 3, which superseded earlier versions such as 2377-22).

A full treatment of competence requirements is in the who can do PAT testing guide.

What the three levels of checking look like

PAT testing is not just the annual formal test. A complete PAT programme involves three levels of checking:

User checks: Before each use, the person using the appliance carries out a quick visual check — is the cable undamaged, is the plug intact, is there any visible sign of damage? This is not a PAT test; it is a basic safety habit. Most organisations build user checks into their induction process.

Formal visual inspection: A more systematic visual inspection by a competent person, conducted at defined intervals. Uses no test equipment but is methodical and documented. This catches visible damage and deterioration that user checks may have missed.

Combined inspection and testing: The full PAT test — formal visual inspection plus electrical measurements using test equipment. The result is recorded in the appliance register and a label is applied to the appliance.

Not every appliance needs all three at every interval. The frequency of each type depends on the risk assessment. For more on the three levels, see the three levels of PAT: user checks, inspection, testing.

What records you need to keep

The test itself is not the compliance evidence. The record is.

A complete PAT record for each appliance should include: a unique identifier for the appliance, a description, the location, the date tested, the type of check carried out, the result, who carried it out, and when the next check is due.

If you use a contractor, they will typically provide a test certificate covering all appliances tested. That certificate forms part of your record. You should also maintain your own appliance register so you can track due dates, disposals, and new additions between contractor visits.

For guidance on record formats and what needs to be captured, see the PAT testing log book guide.

Common misconceptions

"Everything needs to be tested every year." Not true. The appropriate interval depends on the appliance and environment. Many low-risk office appliances are fine on a two-to-four-year inspection cycle.

"If something has a PAT label, it's safe." Labels confirm it passed a test on a specific date. A label from 18 months ago says nothing about whether the cable has been damaged since then. User checks between formal tests are part of the system.

"PAT testing is the same as an electrical inspection." It is not. An EICR (Electrical Installation Condition Report) covers fixed wiring. PAT testing covers portable appliances. The two are separate programmes with separate obligations. For the distinction between the two, see the fixed appliances and PAT testing guide.

"Only a registered electrician can do PAT testing." Not required. A trained, competent person — who does not need to be a qualified electrician — can carry out PAT testing. Competence, not formal trade qualification, is the standard.

Getting started with a PAT programme

If you are setting up a PAT programme for the first time:

Inventory your appliances. Walk through the premises and list every portable electrical appliance in scope. Assign a unique identifier to each.
Assess the risk of each appliance. What type of appliance is it? What environment does it operate in? How often is it used, and by whom?
Determine appropriate intervals. Using the IET Code of Practice or the frequency calculator, set a test interval for each appliance type.
Test and document. Carry out visual inspections and, where appropriate, combined tests. Record results in the appliance register.
Set a schedule for the next cycle. Recurring review dates keep the programme running without needing to rebuild the schedule from scratch each year.

The PAT compliance checker can help verify that your programme design covers the right appliances at the right intervals.

The information in this post reflects the law as of the date last reviewed. The Electricity at Work Regulations 1989 and PUWER 1998 apply in Great Britain rather than UK-wide — EAWR regulation 31 and PUWER regulation 3(1) each say the Regulations "shall apply— (a) in Great Britain" — and a Northern Ireland workplace is governed by the Health and Safety at Work (Northern Ireland) Order 1978 and the Electricity at Work Regulations (Northern Ireland) 1991 instead. Regulations change. Check legislation.gov.uk for current statutory text and HSE.gov.uk for current guidance before making compliance decisions.