Earthing a water pipe??

[ban-all-sheds]

Gone a little bit off topic, no?

Real life is never off-topic.

 

[securespark]

I know I have been guilty of the same, bur there was talk here a long while ago about threads that wander being split from the original topic so they can be continued without bulking out the original query.

 

[sparkwright]

12 pages so far.

Can't read all that lot.

But did the op actually get a straight answer to his question?

 

[JohnW2]

But did the op actually get a straight answer to his question?

He got 'straight answers' in both the first and second responses to his OP back on page 1, but, unfortunately, they were rather contradictory!

His question was whether it was 'pointless' to 'earth' (main bond) an electrically-isolated section of pipework. The first response was that it would not be pointless, because "it will protect the metal pipework should it become live by a fault ensuring the power is automatically disconnected, whilst the second said that it would be pointless, adding that unnecessarily earthing something was potentially dangerous.

There then followed the inevitable discussion about the pros and cons of 'unnecessarily' earthing things. I would imagine that most of us would go with the second of those answers, although which pros outweigh which cons will always be to some extent a matter of person opinion (since it's essentially based on an assessment as to which of two {both rare} possibilities is the more common). The regs certainly do not require the earthing/bonding that the OP was asking about.

Somewhat unusually, the OP participated in some of the initial discussion/argument, for example by expressing concerns about the conductivity of water within a plastic pipe.

I therefore imagine that the OP remained confused/uncertain. However, it's hard to win - speaking personally, if I do what I think is the most useful thing for a DIYer, by pragmatically giving an assertive yes/no answer to a question like this, I often get criticised (and accused of all sorts of things!) for not informing the OP of all the possible situations and all other possible views!

Kind Regards, John

 

[DIYedboy]

Hello gang......................OP here!...................what a wonderful long thread (I usually like the ones where people are having a good old snipe at each other best, but we've had a bit of that too), what was brilliant is getting 2 opposed answers right off the bat (I've decided not to BOND the bit of copper pipe further up the line) and I've learned about how uselessly conductive water in a pipe is, which is rather perverse when one considers that if water is so useless how does it make a wet human in a bathroom waaay more susceptible to electric shock/ death?. John W and all you learned blokes, many thanks

 

[EFLImpudence]

what was brilliant is getting 2 opposed answers right off the bat

That's because the first reply was just plain wrong.

if water is so useless how does it make a wet human in a bathroom waaay more susceptible to electric shock/ death?

It's just the tiny bit which connects your feet and the ground and/or your body part and the live bit.
Your body is nearly all salty water and very little current is required to damage you.

 

[JohnW2]

....and I've learned about how uselessly conductive water in a pipe is, which is rather perverse when one considers that if water is so useless how does it make a wet human in a bathroom waaay more susceptible to electric shock/ death?.

Yes, it does seem a bit perverse - but I think that, despite intuition, one is probably not that much less likely to be electrocuted when dry and away from a bathroom!

However, another point is that it is not so much a question of electricity being 'conducted through the water' when one's skin is wet but, rather, that the resistance of skin to the passage of electric current reduces considerably when the skin is wet.

Kind Regards, John

 

[John D v2.0]

Also it's not necessarily the water that's the whole risk, it's also the amount of metallic parts that may be connected to the electrical installation that are simultaneously touchable and the fact that you're likely to not have shoes or much else on your body. Basically the ideal situation for risk.

 

[JohnW2]

Also it's not necessarily the water that's the whole risk, it's also the amount of metallic parts that may be connected to the electrical installation that are simultaneously touchable ....

I can't speak for others, but I think that there are far more "simultaneously touchable metallic parts that are connected to the electrical installation" in my kitchen, utility room and other places than in my bathroom.

... and the fact that you're likely to not have shoes or much else on your body.

Yes, that is a potential issue - although there are plenty of people who often do not wear shoes (or necessarily even socks) in any room of their house.

It's the sort of information that is probably impossible to find, but I'd be interested to know how the number of electric shocks (fatal or otherwise) in bathrooms compare with those in other rooms (particularly kitchens etc.). The answer might well not be 'as expected'!

Kind Regards, John

 

[ban-all-sheds]

I'd have a shock if I found naked wet people in other rooms in my house.

 

[John D v2.0]

I can't speak for others, but I think that there are far more "simultaneously touchable metallic parts that are connected to the electrical installation" in my kitchen, utility room and other places than in my bathroom.

That is indeed a valid observation and I assume you weren't trying to contradict or clarify my point in any way.
In fact given the previous edition bonding requirements, it probably strengthens my point!
My point being that the whole risk is made up of several factors, not just the conductivity of water.

 

[JohnW2]

That is indeed a valid observation and I assume you weren't trying to contradict or clarify my point in any way.

Not contradicting, but what you wrote could be taken to imply that there are more "simultaneously touchable metallic parts that are connected to the electrical installation" in a bathroom than elsewhere - whereas, as I said, the opposite is the case in my house (and probably many others). In fact, in a plastic-plumbed house, I imagine that there are often no such "simultaneously touchable parts" at all.

In fact given the previous edition bonding requirements, it probably strengthens my point!

I'm not so sure about that, given that 'they' have now deemed supplementary bonding unnecessary everywhere other than (sometimes) bathrooms. Indeed, if I'm not mistaken, if an installation is fully compliant with current regs, then it will inevitably qualify for omission of SB in bathrooms.

My point being that the whole risk is made up of several factors, not just the conductivity of water.

I can't disagree with that. However, I would still be interested to know whether there are more electric shocks in bathrooms than in other rooms/locations (and, frankly, I personally doubt that there are) In my en-suite, for example, about the only way I can think of whereby I could possibly get an electric shock, even if I wanted to, would be by plugging myself in to both sides of an ('isolated') shaver socket!

Kind Regards, John

 

[John D v2.0]

but what you wrote could be taken to imply that there are more "simultaneously touchable metallic parts that are connected to the electrical installation" in a bathroom than elsewhere

If you check the part you quoted I actually said that it merely adds to the risk posed by the water (and nakedness.)
Actually despite me not saying it originally, from your example, it's clear the touchable metal is in fact creating the risk, and merely the impact is affected by the water and nakedness.

So the risk X impact becomes high enough to need mitigation. Unless you have an RCD.

 

[JohnW2]

If you check the part you quoted I actually said that it merely adds to the risk posed by the water (and nakedness.)

I know that, but I still think what you wrote could be taken to imply that it ("the amount of metallic parts ...") was adding more risk in bathrooms than elsewhere. Anyway, I now know that such was not your intention.

Actually despite me not saying it originally, from your example, it's clear the touchable metal is in fact creating the risk, and merely the impact is affected by the water and nakedness.

Fair enough but, as I said, in a house with all-plastic plumbing (not mine), there is probably not going to be any relevant 'touchable metal' in a bathroom, is there? In contrast, it's all over the place in a kitchen, utility room workshop etc.

Kind Regards, John

 

[John D v2.0]

Fair enough but, as I said, in a house with all-plastic plumbing (not mine), there is probably not going to be any relevant 'touchable metal' in a bathroom, is there? In contrast, it's all over the place in a kitchen, utility room workshop etc.

In that case your house is safe without any special mitigation measures.
According to the poster's question it was why does the water pose a danger in the bathroom if it's not very conductive. The answer is the water is a thin layer between the person skin and the metallic parts.
Take either of those away and the need for mitigation is lower.
Or put it another way, water and electricity don't mix.