This is a test which should be carried out on any equipment that is classified as ‘portable’, i.e has a mains lead that can be plugged into a mains outlet at the customers premises. The PAT tester, a piece of test equipment, tests the continuity of the earth lead and any leakage that may be present between the live, neutral and earth wires. If tested ‘OK’ then the equipment should not provide a danger to the customer using it. If tested ‘ok’ then a certificate is issued which should be given to the customer. A copy needs to be kept on file at the repair centre for at least 17 years. PAT testing should be carried out as a routine test if the machine is in a workshop or repair centre environment. It should be carried out on all portable equipment at a customer’s premises on a regular basis.