One of the most common questions we receive is how often PAT testing needs to be carried out. The answer isn't one-size-fits-all — testing frequency should be based on a risk assessment that considers the type of appliance, how it's used, and the environment in which it operates.
The IET Code of Practice
The Institution of Engineering and Technology (IET) publishes the Code of Practice for In-Service Inspection and Testing of Electrical Equipment, which provides recommended testing frequencies. These aren't legal requirements, but they are widely accepted by HSE inspectors and insurance companies as the industry standard.
Recommended Testing Frequencies by Environment
Low-Risk Environments (e.g., offices, schools)
- Desktop computers and IT equipment: Every 4 years (visual check annually)
- Photocopiers and printers: Every 4 years
- Extension leads: Every 4 years
- Portable heaters and fans: Every 1–2 years
Medium-Risk Environments (e.g., commercial kitchens, retail)
- Kitchen appliances (microwaves, kettles): Annually
- Vacuum cleaners: Annually
- Commercial catering equipment: Every 6–12 months
- Retail shop floor equipment: Annually
High-Risk Environments (e.g., construction, industrial)
- Power tools on construction sites: Every 3 months
- 110V site equipment: Every 3 months
- Industrial power tools: Every 6 months
- Battery chargers: Every 6 months
Factors That Affect Testing Frequency
Beyond the IET guidance, several factors should influence your testing frequency decision. Equipment that's moved frequently is more susceptible to damage than fixed equipment. Equipment used in harsh conditions — wet, dusty, or high-temperature environments — degrades faster. Second-hand equipment or appliances with unknown histories should be tested before being put into service, regardless of when they were last tested.
Annual Testing: A Practical Choice
While some low-risk equipment may only need testing every 4 years, many businesses opt for annual PAT testing across all equipment for practical reasons. Annual testing simplifies compliance management, reduces administrative burden, and provides regular reassurance that all equipment in your premises is safe. It's also easier to explain to insurers, HSE inspectors, and Ofsted.
When Should Equipment Be Tested Immediately?
- Before first use if the equipment's history is unknown
- After any repair or modification
- After any incident (drop, flood, electrical fault) involving the equipment
- When equipment is moved from one premises to another
- If a visual inspection reveals any damage or deterioration
