The IET's 5th Edition Code of Practice renames PAT testing as electrical equipment testing (EET). We explain what has changed, what has stayed the same, and what it means in practice.
What has changed?
The Institution of Engineering and Technology (IET) published the 5th Edition of its Code of Practice for In-Service Inspection and Testing of Electrical Equipment in 2025. The most visible change is a renaming: what has been known as PAT testing — portable appliance testing — is now formally referred to as electrical equipment testing, or EET.
The renaming reflects a long-standing criticism of the term PAT testing: it implied that only portable appliances needed to be tested, when in fact the inspection and testing regime covers a much wider range of equipment including stationary, fixed, and IT equipment connected to the mains via a plug and socket.
What has stayed the same?
The underlying technical requirements, test methods, and pass/fail criteria remain substantially the same. The 5th Edition does not introduce new tests or change the fundamental approach to in-service inspection. The same equipment — earth continuity testers, insulation resistance testers, and combined PAT testers — is used to carry out the work.
The legal framework is also unchanged. The Electricity at Work Regulations 1989, the Health and Safety at Work Act 1974, and sector-specific guidance such as HTM 06-01 for healthcare settings remain in force.
Why does the name matter?
For most businesses, the renaming is largely cosmetic. The term PAT testing remains widely understood and will continue to be used in everyday conversation for years to come. However, there are a few practical implications:
Documentation. Test certificates and asset registers issued under the 5th Edition may refer to electrical equipment testing or EET rather than PAT testing. This does not affect their validity.
Procurement. When tendering for testing services or reviewing contractor documentation, businesses should be aware that EET and PAT testing refer to the same activity.
Compliance language. In sectors where compliance documentation is scrutinised — healthcare, education, aviation — using the current IET terminology demonstrates awareness of the latest guidance.
What the 5th Edition changes in practice
Beyond the renaming, the 5th Edition includes updated guidance on:
- Risk assessment: greater emphasis on a documented, risk-based approach to determining testing intervals, rather than applying default intervals without justification
- IT equipment: revised guidance on testing intervals for IT equipment, reflecting the prevalence of Class II double-insulated devices
- Formal visual inspection: clearer guidance on what constitutes a formal visual inspection and how it should be recorded
- Competence: updated guidance on what constitutes competence for carrying out inspections and tests
Does this affect my legal obligations?
No. The IET Code of Practice is guidance, not legislation. Your legal obligations under the Electricity at Work Regulations 1989 and the Health and Safety at Work Act 1974 are unchanged. The 5th Edition provides the most current best-practice framework for meeting those obligations, but it does not create new legal duties.
Sector implications
NHS and care homes: HTM 06-01 remains the primary guidance for healthcare settings. The 5th Edition is complementary to HTM 06-01 rather than replacing it. Annual testing of Class I equipment in clinical and care environments remains standard practice.
Schools: The 5th Edition updates suggested intervals for educational establishments. IT equipment intervals remain at 4 years for low-risk environments, with annual testing recommended for Class I equipment.
Airports: High-use public environments continue to warrant annual testing of most equipment classes.
Offices: The risk-based approach is particularly relevant for office environments, where a large proportion of equipment is Class II IT equipment that may not require testing as frequently as Class I appliances.
Multi-site operations: Organisations with multiple premises should ensure their testing programmes are updated to reflect 5th Edition terminology and risk-assessment requirements.
Compliance: The 5th Edition strengthens the case for documented risk assessments as the foundation of any testing programme.
Location coverage
Maritime Electrical Services provides electrical equipment testing across Kent, London, Essex, Surrey, West Sussex, East Sussex, Hertfordshire, Cambridgeshire, Brighton, Guildford, Watford, Dartford, Medway, Canterbury, Tonbridge, Colchester, Brentwood, Braintree, Horsham, Central London, and all surrounding areas.
Contact us to discuss your testing requirements under the updated IET 5th Edition framework.
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