<P> Electrical bonding is the practice of intentionally electrically connecting all exposed metallic items not designed to carry electricity in a room or building as protection from electric shock . If a failure of electrical insulation occurs, all bonded metal objects in the room will have substantially the same electrical potential, so that an occupant of the room cannot touch two objects with significantly different potentials . Even if the connection to a distant earth ground is lost, the occupant will be protected from dangerous potential differences . </P> <P> In a building with electricity it is normal for safety reasons to connect all metal objects such as pipes together to the mains earth to form an equipotential zone . This is done in the UK because many buildings are supplied with a single phase supply cable where the neutral and earth conductors are combined . Close to the electricity meter this conductor is divided into two, the earth terminal and the wire going to the neutral busbar in the consumer unit . If the ground connection to the neutral is lost, all wiring and other objects tied to the neutral will be energized at the line voltage . Examples of articles that may be bonded include metallic water piping systems, gas piping, ducts for central heating and air conditioning systems, and exposed metal parts of buildings such as hand rails, stairs, ladders, platforms and floors . </P>

An equipotential bond connects two parts of a telecommunications earthing systems together