EICR Supplementary bonding Question

Liam London · Jun 15, 2014

Hi all

new to this forum but had a question regarding an EICR I have underway at the moment. It has so far failed miserably 50 C3's and about 10 C2's on day one of four.

My main query is this

it has metallic conduit fixed via self tappers into metallic walls and ceilings split into sections by RSJ's. The walls are a type of steel but each section between RSJ's is made up of about 3 sheets of metal screwed together.

i have verified earth continuity between conduit trunking and all metal work. But is this an acceptable earthing method. If any section of wall was to be removed this would render sections of the metal work no longer connected to earth but with conduit still running on it the metal would of course be touching the conduit but not fixed to it via self tappers!

surely self tappers aren't an appropriate earthing path any way?

i would think I would at least need to put an earth safety connection do not remove label between sheets or actually put a metallic bond between each sheet? And label it all? Very poorly done job but they want it brought up to 17th edition just wondered what you guys take would be on it as it seems a grey area.

the problem is they could get an unskilled person to swap a metallic wall for wood in an area so they could make a notice board or something and disconnect large parts of metal work from earth???

Any advice or help would be greatly appreciated

many thanks

Liam

Parker27 · Jul 15, 2014

I would mention this as a C3 improvement recommendation to cover myself, if they do not want you to bond individual steel sheets or the RSJ's thats down to them - At least you have told them.

Risteard · Jul 16, 2014

A bit confused why you want to earth the wall. It's hardly an exposed conductive part.

Geordie Spark · Jul 16, 2014

Risteard said:
A bit confused why you want to earth the wall. It's hardly an exposed conductive part.

Do you remember a little while back a lady was electrocuted when she was mopping water from her bathroom floor?

That was because some metalwork in the wall became live and it wasn't bonded / earthed or whatever.

Engineer54 · Jul 16, 2014

Liam London said:
Hi all

new to this forum but had a question regarding an EICR I have underway at the moment. It has so far failed miserably 50 C3's and about 10 C2's on day one of four.

My main query is this

it has metallic conduit fixed via self tappers into metallic walls and ceilings split into sections by RSJ's. The walls are a type of steel but each section between RSJ's is made up of about 3 sheets of metal screwed together.

i have verified earth continuity between conduit trunking and all metal work. But is this an acceptable earthing method. If any section of wall was to be removed this would render sections of the metal work no longer connected to earth but with conduit still running on it the metal would of course be touching the conduit but not fixed to it via self tappers!

surely self tappers aren't an appropriate earthing path any way?

i would think I would at least need to put an earth safety connection do not remove label between sheets or actually put a metallic bond between each sheet? And label it all? Very poorly done job but they want it brought up to 17th edition just wondered what you guys take would be on it as it seems a grey area.

the problem is they could get an unskilled person to swap a metallic wall for wood in an area so they could make a notice board or something and disconnect large parts of metal work from earth???

Any advice or help would be greatly appreciated

many thanks

Liam

You base your report findings on the installation as is, NOT on what it might or could be in the future, that's not your concern....

The conduit and trunking installation will or should be earthed at the origin of the containment system(s) so the use of self tapping fixing screws is neither here nor there. There should be a main bonding conductor that connects to the building steel work to the installations MET....