PAT testing is an important testing process in the UK, Republic of Ireland, Australia and New Zealand by which portable appliances are required to be checked for safety standards. The Health and Safety at Work Act of 1974 was the first legislation that required companies to have their electrical equipment tested on a regular basis. The Management of Health and Safety at Work Regulations of 1999 established further requirements for PAT testing. Health and safety regulations require that portable electrical appliances in the workplace operate in a safe manner that prevents any potential harm to employees. By law, all electrical systems must be properly inspected and tested for defects and safety.
The law allows companies to gauge their electrical appliances in-house, which allows for more flexibility during the process. However, many companies hire an external company that has employees qualified to perform PAT testing. All testers must have extensive knowledge of electrical systems and they must be officially qualified to perform PAT. Each tester must have a sufficient understanding related to the modes of electrical, thermal and mechanical damage that may result from damaged or poorly designed equipment. There are four different testing situations designated by the IEE Code of Practice:
1) Type testing to an appropriate standard. This type involves testing to determine whether the electrical equipment meets the designated requirements. Type testing is frequently performed by external organizations.
2) Production calibration. Production calibration involves testing the electrical appliance during the production of the appliance and before it is released into service. Production testing is important to prevent unsafe appliances from being utilized by workers.
3) In-service testing. In-service testing involves a preliminary inspection, continuity tests, insulation testing and functional checks. In-service testing is performed to provide certainty that electrical appliances are currently in satisfactory condition. If an electrical appliance fails this test, it must either be repaired or replaced.
4) Testing after repair. If an electrical appliance was in unsatisfactory condition and has been repaired, tests must be performed to ensure that the repairs were sufficient to restore the appliance to satisfactory condition.
The level of testing required for portable electrical appliances is largely dependent on the risk associated with the specific appliance. To ensure that electrical appliances are safe in the home and in the workplace, it is important to perform PAT testing on a regular basis. This can often be done on site by calling out a PAT tester, many can be found online in local areas.