Portable Appliance Testing Statistics UK: 2026 Facts, Data & Key Insights

What Is PAT Testing?

Portable Appliance Testing (PAT) — now also known as Inspection and Testing of Electrical Equipment (ITEE) — is the systematic inspection and electrical testing of portable and moveable electrical equipment to verify that it is safe for continued use. It is the primary mechanism through which UK employers discharge their legal duty under the Electricity at Work Regulations 1989 to maintain portable electrical equipment so as to prevent danger.

PAT testing involves two components: a visual inspection to identify obvious damage, wear, or defects; and electrical testing using a specialist PAT tester to verify earth continuity, insulation resistance, and other electrical parameters. Together these two stages identify faults that could cause electric shock, burns, or fire if the appliance continued to be used.

For the broader electrical safety context, see our Electrical Accident Statistics UK guide and Electrical Fire Statistics UK guide.

Key Facts & Figures (Overview)

PAT Testing and the Law

A persistent source of confusion in the UK PAT testing landscape is the legal status of the requirement. The position is clear:

There is no specific law that says electrical appliances must have a PAT test label or certificate. The Electricity at Work Regulations 1989 do not mention PAT testing by name.

What the law does require, under Regulation 4(2) of the Electricity at Work Regulations, is that all electrical systems — which includes electrical appliances — are maintained to prevent danger. The manner in which this duty is discharged is left to the duty holder, with PAT testing being the most widely recognised and practically effective method.

This means that PAT testing is not mandated by law — but the duty it discharges absolutely is. An employer who cannot demonstrate that portable appliances are maintained in safe condition faces the same legal exposure as one who has clearly failed to test, regardless of how the maintenance was achieved.

For most workplaces, PAT testing is the most practical, cost-effective, and evidentially robust method of demonstrating compliance. It creates a documented record of inspection and testing results that can be produced in the event of an HSE investigation, insurance claim, or civil litigation.

What PAT Testing Finds: Failure Rates and Fault Types

Research by Seaward — one of the UK's leading PAT test instrument manufacturers — analysed appliance failure rates from routine workplace testing programmes across a large sample of sites. The data reveals:

The most common failure types identified by PAT testing:

Damaged cables and wiring — frayed or exposed wires, cables with visible cuts or abrasions, improperly repaired cords — the most commonly identified visual defect category.

Faulty plugs — cracked or broken plugs, incorrect fusing, improper internal wiring. Incorrect fusing is particularly hazardous as it removes the primary overcurrent protection.

Inadequate insulation resistance — electrical testing identifies faults in the insulation of appliance wiring that would not be visible on external inspection. A failed insulation resistance test indicates that current could leak to accessible parts of the appliance, creating electric shock risk.

Failed earth continuity — Class I appliances rely on an earth connection to provide a safe route for fault current. A failed earth continuity test means that in the event of a live-to-earth fault, the appliance casing could become live at mains voltage.

Signs of overheating — scorch marks, discolouration, and melted plastic around plugs and cable ends indicate that previous overheating has occurred — a warning sign of fire risk.

Appliances that fail most frequently:

PAT Testing Frequency: The Risk-Based Approach

There is no single legally mandated testing interval. Testing frequency must be determined by risk assessment, taking into account the type of equipment, the environment in which it is used, and the frequency and intensity of use.

HSE guidance and the IET Code of Practice for In-Service Inspection and Testing of Electrical Equipment provide suggested testing intervals:

Construction sites and industrial environments: Equipment in these environments is subject to physical damage, exposure to the elements, and heavy use — suggesting testing intervals of 3 months to 1 year for most equipment classes.

Commercial kitchens and catering: High thermal stress, moisture, and intensive daily use justify intervals of 6 months to 1 year.

Offices and low-risk environments: Desktop computers, monitors, and similar equipment in clean, dry, low-risk office environments may only need testing every 2–4 years — the HSE has specifically noted that annual PAT testing is often disproportionate for low-risk office equipment.

Schools: ICT equipment and general classroom appliances typically require annual testing, with higher-risk equipment in science laboratories and workshops tested more frequently. See our School Electrical Safety Statistics UK guide.

Rented accommodation: Landlords are responsible for portable appliances they supply with the tenancy. PAT testing of these appliances at tenancy change is standard practice. See our Landlord Electrical Safety Statistics UK guide.

User checks: Regardless of formal testing intervals, all portable appliance users should carry out a visual check before each use — looking for damaged cables, broken plugs, scorch marks, and other obvious defects.

Who Can Carry Out PAT Testing?

The requirement is for a competent person — defined as someone who has sufficient knowledge, experience, and skills to carry out the inspection and testing safely and to interpret the results correctly.

For formal electrical testing (as opposed to visual inspection alone), this typically means:

In-house testing by a trained employee is entirely legal and widely practised, particularly in larger organisations. External specialist PAT testing contractors are widely used for smaller organisations or where the volume of equipment makes internal testing impractical.

PAT Testing Records and Documentation

Accurate record-keeping is a critical component of any PAT testing programme. Records should capture:

These records serve multiple purposes: demonstrating compliance to the HSE in the event of an investigation, supporting insurance claims following an incident, and creating an audit trail for ongoing management of the testing programme.

Appliances that fail testing must be clearly labelled "Do Not Use" and removed from service immediately. They must not be returned to use until they have been repaired and retested by a competent person, or safely disposed of.

Written by Electrical Safety Experts

This guide was produced by the team at PAT Testing Course, a UK provider of City & Guilds and LCL Awards-accredited PAT testing training. Our courses give individuals the competence to carry out in-house PAT testing legally and effectively — understanding not just the practical testing procedures but the legal framework, risk assessment principles, and record-keeping requirements that underpin a compliant programme. For related data see our Electrical Accident Statistics UK, Electrical Fire Statistics UK, Workplace Electrical Safety Statistics UK, and sector-specific guides.

Sources & References