Earth wire connected to internal water pipes, why

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When the house was rewired in 1983 the electricians attached a green and yellow cable with a metal label stating "Safety electrical connection. BS951 Do not remove" to some of the copper water pipes in bathroom and kitchen. What does this do?

I am replacing the metal mains water supply pipe with a plastic one. Will this have any implications for electrical safety please. Explanations in easy terms would be appreciated. The cost to replacing the pipe is very expensive and I really don't want another expense for the electrics. Thank you
 
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It’s the main equipotential earth bonding arrangement, it’s there to protect the end user (you) should a live wire accidentally touch any part of the water system, eg a bath tap, or kitchen sink tap. Are you replacing the incoming main or from the stopcock upwards (rising main)? If the latter, are you replacing all copper or just parts?

More detailed information here: https://www.diynot.com/wiki/Electrics:main_equipotential_bonding
 
It’s the main equipotential earth bonding arrangement, it’s there to protect the end user (you) should a live wire accidentally touch any part of the water system, eg a bath tap, or kitchen sink tap. Are you replacing the incoming main or from the stopcock upwards (rising main)? If the latter, are you replacing all copper or just parts?

More detailed information here: https://www.diynot.com/wiki/Electrics:main_equipotential_bonding

Thanks for your reply. I am only replacing the incoming main as it is leaking and has already one repair 3 or 4 years ago and possibly the stopcock in the house. Sorry to be stupid but I don't understand the contents of the link as I know nothing about plumbing or electricity. Do I need to do anything about the electrics after the supply pipe is replaced with a plastic one.
 
Providing you’re not removing the earth bonding, then no.
 
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Yes, the label that states - do not remove electrical connection.

Thanks Chris. Sorry for all the stupid questions. I've been in a panic since I developed a water feature in my garden i.e. a fast flowing stream from my mains water supply pipe two days ago.
 
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Thanks Chris. Sorry for all the stupid questions. I've been in a panic since I developed a water feature in my garden i.e. a fast flowing stream from my mains water supply pipe two days ago.
No it’s not stupid, if you didn’t ask, you’d be none the wiser ;)
 
It’s the main equipotential earth bonding arrangement, it’s there to protect the end user (you) should a live wire accidentally touch any part of the water system, eg a bath tap, or kitchen sink tap.
That's not actually the purpose of 'bonding'.

Equipotential Bonding is to equalise the potential (Voltage) between parts which may become live during a fault.



When the house was rewired in 1983 the electricians attached a green and yellow cable with a metal label stating "Safety electrical connection. BS951 Do not remove" to some of the copper water pipes in bathroom and kitchen. What does this do?
In the kitchen if it is connected to the incoming supply - as above.

In the bathroom it is known as Supplementary Bonding and further equalises potential in hazardous locations.

I am replacing the metal mains water supply pipe with a plastic one. Will this have any implications for electrical safety please.
If you mean the supply pipe and no metal pipes remain in contact with the ground, the bonding will no longer be necessary.
 
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That's not actually the purpose of 'bonding'.

Equipotential Bonding is to equalise the potential (Voltage) between parts which may become live during a fault.




In the kitchen if it is connected to the incoming supply - as above.

In the bathroom it is known as Supplementary Bonding and further equalises potential in hazardous locations.


If you mean the supply pipe and no metal pipes remain in contact with the ground, the bonding will no longer be necessary.

I have one in the kitchen and one in the bathroom. I am waiting to see if I have any metal pipe in contact with the ground or not after the repair.
 
I have one in the kitchen and one in the bathroom. I am waiting to see if I have any metal pipe in contact with the ground or not after the repair.
The one in the kitchen is probably the Main Bonding Conductor on the incoming supply pipe and runs to the Main Earthing Terminal in or near the consumer unit.

You might have the same in the bathroom if a pipe emerges from the ground but it is more likely the Supplementary Bonding Conductors which just connect together the local pipes.
 
When I say 'pipe' I of course only mean metal ones.

You cannot bond plastic ones as the plastic does not conduct electricity.
 
I've just had a quote from my local water company to replace the pipe. Included in the quote details was this information

"You need to be aware that if your property uses a metal water service pipe as a means of earthing, this is not regarded as a safe method of installation and has been prohibited since 1966. Buildings built before that date may still be earthed in this way. Recent work may make such existing systems ineffective as well as unacceptable We would emphasise that the earthing of a property is an essential safety requirement and is the sole responsibility of the owner of the property."

Are they talking about something different from what I have or is it the same thing. My house was rewired in the early 1980s which was after it was prohibited. I am now confused.
 
Earthing and bonding are two different things, you have nothing to worry about. The connection to your incoming pipe is bonding not earthing.
 

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