For appliances that are used in the area of electrical systems must be certified or checked documents from those tests and monitoring in accordance with the rules of the Ministry of Finance on the qualification test and check the oil.
For appliances that are used in hazardous areas of the electrical system must be documented, endorsed or certified by testers and examination under the regulations governing the qualifications of the tester and check the oil.
For appliances used in the danger of electric system must have a certificate or received accreditation from the test and inspection according to regulations on the qualification of the test and inspection of oil