The Electricity at Work Regulations 1989 places a duty on Employers, Self-Employed and Employees to ensure that electrical equipment is maintained, so far as it reasonably practicable, so to prevent risk. The Regulations do not stipulate how this is done and the safety testing or frequency is not written in law however the Health and Safety Executive have produced Guidance to help those duty holders that the Regulations identify achieve compliance for Portable Electrical Equipment and one example of this is the document HSG107 Maintaining Portable Electrical Equipment. In this guidance the frequency of safety testing is identified according to the type of equipment and the type of testing is also suggested. 
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