The electrical system in any building is likely to include equipment designed to transmit energy from the incoming mains or other source, and from the means of connection and control to electrical equipment and lighting within the property.
Dangers from electricity can be caused by several factors including:
- faulty electrical equipment
- defective or damaged electrical installations
- overloading of electrical installations
- equipment that is inappropriate to the location or circumstances in which it is used
- cable supports failing under fire conditions resulting in the entanglement of fire fighters
Controlling these requires maintenance and inspection of electrical equipment, the correct use of such equipment and the provision of appropriate cable support along with physical protection, protection devices and earthing.
All electrical installations require periodic testing and inspection to ensure they are safe for use. In the case of apartment blocks this is specific to the communal areas of the property, and guidance suggests that testing should be completed every five years. Fixed electrical equipment will also need inspection and testing and it should be ensured that relevant tests and inspections are undertaken as part of the planned maintenance routine for the property. New installations or changes to an existing installation should be provided with an Electrical Installation Certificate giving details of initial electrical test results.
Electrical testing criteria and procedures are set out in BS 7671: 2018, Requirements for Electrical Installations, the IET Wiring Regulations 18th Edition, and the IET Guidance Note 3: Inspection and Testing. These tests should be performed and certified by an accredited person or inspection body. These are typically members of the National Inspection Council for Electrical Installation Contracting (NICEIC), NAPIT electrical registration scheme or the Electrical Contractors Association (ECA).
Faults detected from electrical inspections and testing are normally classified as Codes C1, C2 or C3. These have the following meaning:
- Code C1: “Danger present’’. Risk of injury. Immediate remedial action required.
- Code C2: “Potentially dangerous”. Urgent remedial action required.
- Code C3: “Improvement recommended”.
Other coding may indicate the need for further investigation to determine the safety of an aspect of the installation. C1 faults will require immediate resolution, with work to remedy C2 faults and further investigations being conducted as soon as practicable.
The inspecting organisation will issue certificate stating that the installation is satisfactory once any necessary remedial works and further investigations have been completed.