Well, the distance is surely relevant if large.
In some respects (particularly VD and Zs), obviously, but I don't see it as being relevant to the theoretical risk associated with exporting a PME earth outside of its equipotential zone.
as I said, it's all about taking a PME earth outside of the equipotential zone.
Are we talking about tools or sheds?
As I've said (several times I think!), either or both (and also taps, metal waste pipes etc.). Tools are really only an issue if they are Class I, which would be pretty rare.
If one built an extension which reached three-quarters of the way down one's garden, 'overtaking' sheds as it did, the entire inside of that extension would surely be included as part of the house's equipotential zone?
Yes, but what is the difference?
The difference between what and what? Do you mean, say, the difference between the far end of a house extension and an outhouse at the same distance from the original house before extension? If so, the difference is that the outhouse will commonly contain, or be adjacent to, essentially unbondable paths to truth earth (e.g. potentially wet soil), whereas such is pretty rare within a house (or house extension).
Yes, but I am not considering lost neutrals.
What
are you considering then? As I've been saying (on their behalf) 'lost neutrals' are surely the main concern of those worried about the export of PME earths. Once one has decided not to consdier that, the only other downsides ofexporting a PME earth are matters of convenience, aren't they (particularly the need to provide adequate bonding of any extraneous-c-ps), aren't they?
I am saying that extending the zone to a shed or garage is no different than building an extension where the new kitchen is in the same place as the shed or garage was. ... No one would think of TTing the kitchen or give a second thought to washing the kitchen floor.
Not usually, but if, like one of my daughters, one lived in an ancient cottage whose kitchen floor consisted of flagstones and quarry tiles, grouted with sand and laying directly on sand and soil, I suppose that you might at least consider the possibility. Even under 'normal wet conditions' (let alone recent months), the floor is often sodden with water welling up between the tiles/stones. That must be very rare in a house, so your comment is correct in relation to nearly all kitchens, but outhouses are not uncommonly similar to my daughter's kitchen (and often immediately adjacent to potentially wet soil).
So, as I think we're both saying, one needs to consider the particular situation. However if, as you've said above, you are prepared to discount the possibility of a 'lost neutral' (and I can't really argue, given the rarity of that, and even greater rarity of it presenting a significant risk), then I think you really only have 'convenience', rather than safety, issues to consider when decided whether or not to export a PME earth.
Kind Regards, John
