No, there's no legal frequency. Here's what the Electricity at Work Regulations actually require.
The Electricity at Work Regulations 1989 require that all electrical systems -- including portable appliances -- are maintained in a safe condition. The legislation does not specify PAT testing or any particular frequency. Portable Appliance Testing is one method of demonstrating compliance with the maintenance duty -- but frequency must be determined by risk assessment, not by a blanket calendar.
Classify equipment by environment and risk profile: clinical care equipment (hoists, electric profiling beds, electric bathing equipment) -- annual test; kitchen equipment -- annual test; office equipment -- every 2-4 years depending on age and condition. A blanket annual test for all equipment wastes money and does not reflect a genuine risk-based approach.
Visual user checks before each use are important and are not a substitute for formal testing -- but they catch the most common defects at the point they arise. A defect reporting log demonstrates that the user-check regime is functioning.
For each item tested: unique asset identifier, location, test date, pass/fail result, and the tester's name and accreditation. Items that fail must be removed from service immediately. Retain PAT records for the life of the appliance.
PAT testing is triggered by: the risk-assessed frequency schedule, any visual defect identified, any incident involving an appliance, any significant use change, or any appliance returned from outside the premises. Newly received appliances should be tested before first use in a care setting.
CareHomeDesk gives you compliance checklists, maintenance logs, and contractor management tools built around exactly this kind of knowledge.