Briefly put, PAT testing was launched to ensure that all electrical appliances are safely maintained and suitable in the environment in which they are used. This involves periodic planned inspection and testing of all portable appliances so they meet all required standards and regulations. The Electricity at Work Regulations states that it is a legal requirement that employers maintain their electrical systems at work to prevent any danger.
Health and Safety Legislation
The legislation relevant to electrical maintenance is the Health and Safety at Work Act 1974, the Management of Health and Safety at Work Regulations 1999, the Electricity at Work Regulations 1989, the Workplace (Health, Safety and Welfare) Regulations 1992 and the Provision and Use of Work Equipment Regulations 1998. The Health and Safety at Work act 1974 places the duty of care upon both the employer and the employee to ensure the safety of all persons using the work premises.
The IEE Code of Practice
The IEE Code of Practice for In Service Inspection and Testing of Equipment sets out the standard to which each appliance is comprehensively tested. The inspection and testing should be carried out by a fully qualified City and Guilds 2377 PAT testing technician.
Tests Undertaken
Once an appliance has passed the visual inspection the equipment may now be tested for electrical safety using the following tests
Earth Continuity This first test ensures that an earth is present between the metalwork of an appliance and the earth pin of the plug. This test is carried out on all class one and some class three equipment.
Insulation Resistance This test is carried out on all classes of equipment. The test is to ascertain any breakdown in the insulation protecting the conductors.
Formal Visual Inspection The Formal Visual Inspection may form part of the combined inspection and tests when they coincide, and will be recorded.
Earth Leakage This test measures the leakage current of earth during the operation of the appliance and is also carried out on all classes of equipment.