Earth Bonding

“Electrical bonding is the practice of intentionally electrically connecting all exposed metallic non-current carrying items in a room or building as protection from electric shock.”
Source: Wikipedia.org

If a failure of electrical insulation occurs, all bonded metal objects in the room will have substantially the same electrical potential (i.e., voltage) so that an occupant of the room cannot touch two objects with significantly different potentials (i.e. voltage)”.

We say all metal pipe work that could come into contact with electrical wires under the floor should be connected to each other and then to the fuse board this way if any live wire touches the metal pipe under a fault condition the fuse or MCB would disconnect the 230v supply.

There normally needs to be a main earth cable from the main earth (green & yellow) connection at the fuse board to the gas and water supply pipe into the building.

Then normally at the boiler we connect the mains water pipe to the other pipes that are the flow & return on the heating system, mains gas supply pipe, hot water pipe. Basically at this position we can earth all other pipes in the property unless plastic poly pipe has been used on your property?

In the bathroom especially we connect the tin or cast iron bath to the towel rail and then to the sink supply pipes, all of the above is a must if you have an older type of fuseboard check your fuseboard here.

Different potentials means voltage differences say pipe one (Hot water) is at 20 volts live because an electrical cable passes over the top of it three times along its run and pipe two (Heating pipe) has a cable running next to it for its entire run and sits there at 120 volts live.

Now you are in the bath which is at 20 volts live because the hot water pipe connects to the tin bath and you lean across the room as I do to get a towel off the hot towel rail connected to the heating pipes at 120 volts live. Now electricity flows to the lowest potential so basically you just become the electrical conductor between these stray voltages 20v and 120v and 100 volts flows through you and this voltage could be life threatening when you body is wet and at it lowest resistance and a better conductor for electricity.

Now if earth bonding was installed as explained above then these stray voltages would have been dumped to the main earth terminal and all pipes would be at 0 volts thus making you safer.

Property owners, landlords, tenants read this leaflet on checking earth bonding and call us today to get yours checked.