Why is earthing and earth bonding so important?
If you are having an alteration or an addition made to your electrical installation, your electrician must check (as well as other things) that the earthing and bonding arrangements you have are up to the required standard.
This is because the safety of any new work you have done (however small) will depend on the earthing and bonding arrangements.
What is earthing?
If there is a fault in your electrical installation you could get an electric shock if you touch a live metal part. This is because the electricity may use your body as a path from the live part to the earth part.
Earthing is used to protect you from an electric shock. It does this by providing a path (a protective conductor) for a fault current to flow to earth. It also causes the protective device (either a circuit-breaker or fuse) to switch off the electric current to the circuit that has the fault. For example, if a cooker has a fault, the fault current flows to earth through the protective (earthing) conductors. A protective device (fuse or circuit-breaker) in the consumer unit switches off the electrical supply to the cooker. The cooker is now safe from causing an electric shock to anyone who touches it. The speed in which this process happens is vitally important to protect people from experiencing potentially life threatening levels of shock. It is essential that this part of your installation is kept up to date and in good condition, if you have a concern regarding the earthing in your property contact your local office for advice.
What is bonding?
Bonding is used to reduce the risk of electric shocks to anyone who may touch two separate metal parts when there is a fault somewhere in the supply of electrical installation. By connecting bonding conductors between particular parts, it reduces the voltage there might have been. The most common parts that are bonded are your incoming water pipes and gas pipes, this allows protection throughout your property should a cable come into contact with a pipe or for example a water heater develops a fault that could prove dangerous. If you’re not sure if your incoming gas or water supply is bonded contact your local office for advice.
We strongly recommend that you use an approved electrician such as ElectriciansOnCall for any work that involves your earthing or bonding, we have been advising clients since 1997 and are experienced with all types of installations. This vital piece of equipment may well save your life one day
Bonding - A way of reducing the risk of getting an electric shock.
Conductors - Wires that carry electricity.
Consumer Unit - A fusebox that is used to control and give out electricity around the home. It usually contains a main switch, fuses or circuit-breakers and one or more residual current devices (RCDs).
Current – The flow of electricity.
Earth - A connection to the ground.
Earthing - A way of preventing electric shocks.
Electrical installation - A fixed wiring system.
Live - Active (there is electricity).
Main bonding - Green and yellow conductors that connect metal pipes (gas, water or oil) from inside a building to the main earthing terminal of the electrical installation. Main bonding connections may also be made outside the building, for example where a semi-enclosed gas meter box is installed outside and it is not possible to install a bond to the gas installation pipework indoors.
Main earthing terminal - Where earthing and bonding conductors are connected together.
Residual current devices (RCDs) - A sensitive switching device that trips a circuit when it finds an earth fault.
Supplementary bonding - Green and yellow conductors that connect accessible metal parts of electrical equipment (such as a heated towel rail) to accessible metal parts of items of electrical equipment and/or accessible metal parts of items that are not electrical (such as pipes and radiators). These connections are made to prevent a dangerous voltage between two accessible metal parts, in case there is a fault. You may need supplementary bonding for rooms containing a bath or shower, except where all circuits in the room are RCD protected and the main bonding is up to the required standard.
Voltage - The force of electricity.
If you have any concerns about earthing, bonding or a general enquiry regarding your electrical installation contact your local office today for advice, to arrange an appointment or to arrange immediate assistance for an electrical fault.