For those who don't read the electrical forum but play with plumbing

[cyclic]

https://www.vision6.com.au/em/mail/v...5149&k=bbac61d

[chrisp]

For those who are unaware, the general recommendation when cutting or undoing metal water pipes or metal gas pipes is to use a jumper lead across the break or cut or disconnection so that if there is an earth or neutral fault in the electrical system that you don't get electrocuted.

[PlatypusGardens]

Well.....how the hell are you supposed to avoid that.....?

Workplace Health and Safety Queensland and the Electrical Safety Office are investigating a fatal electrical incident that happened on Sunday 9 October 2016 at Ayr.A man died after he received an electric shock while cutting a metal water pipe to repair a leak.


First inspections revealed that the neutral line from the power pole to the house had come away from the pole and did not provide a return path from the house, instead the water pipe had become the return path.

This alert is to remind you and your organisation to be safe around electricity.

It says "A man"....so was he a licensed plumber or not......doesn't really matter when the electricity is running through the plumbing.....you'd be screwed regardless

[sol381]

indeed..."This alert is to remind you and your organisation to be safe around electricity."..Duh.. well he wasnt playing with electricity..

[phild01]

How common is it for that to happen at the pole?

[Bros]

This happened in Ayr in NQ and the incident I was involved in happened at Giru 50 klm north. I wouldn't be surprised if it was a common occurrence.

[Bros]

For those who are unaware, the general recommendation when cutting or undoing metal water pipes or metal gas pipes is to use a jumper lead across the break or cut or disconnection so that if there is an earth or neutral fault in the electrical system that you don't get electrocuted.

If you think about that recommendation you will realise how silly it is. You cut a pipe that is part of the return and you are left with a cable that is alive. The only way is turn off the main switch.

[cyclic]

If you think about that recommendation you will realise how silly it is. You cut a pipe that is part of the return and you are left with a cable that is alive. The only way is turn off the main switch.

Then test to make sure there is absolutely no current at the pipe.

[Marc]

So the earth is acting as neutral. That should trigger the safety switch right?

[phild01]

So the earth is acting as neutral. That should trigger the safety switch right?

I think it needs neutral to know.

[Bros]

Then test to make sure there is absolutely no current at the pipe.

Not putting plumbers down but it would be above their pay scale to test for current flow.

[Bros]

So the earth is acting as neutral. That should trigger the safety switch right?

No it won't as the neutral is before the RCD.

[PlatypusGardens]

Not putting plumbers down but it would be above their pay scale to test for current flow.

Well....how often has this happened?
Would any plumber out there ever check if a pipe is electrified before cutting it?


Seriously...this is a freak accident.




.....unless a licenesed sparky didn't do their job properly and didn't properly connect that cable which "came away".........


.....huh...

[Bros]

There is another parallel path which should have saved him and that was the earth stake. The water pipe in only a bonding to bring the water pipes down to earth potential not as an earth return. The earth stake is the main earth and the water pipe should not have caused any problems. Obviously the house electrical system was substandard.

[chrisp]

Plumbers are trained during their apprenticeship years to connect bonding cables, typically battery jumper leads, across the water pipe point to be breached before all work is started.

Quote from: Avoid electrical shocks when working with water supply mains - Environment and Planning Directorate - Planning

[ringtail]

Plumbers are trained during their apprenticeship years to connect bonding cables, typically battery jumper leads, across the water pipe point to be breached before all work is started.

Have never and dare I say will never see a plumber (or anyone else) do that.

[chrisp]

There is another parallel path which should have saved him and that was the earth stake. The water pipe in only a bonding to bring the water pipes down to earth potential not as an earth return. The earth stake is the main earth and the water pipe should not have caused any problems. Obviously the house electrical system was substandard.

Correct - it is probably two faults that caused the death - but it happens.

[Marc]

Have never and dare I say will never see a plumber (or anyone else) do that.

My son in law came to do some work when we did the bathroom renovation and I saw him earthing the old pipework before cutting it.

[chrisp]

Have never and dare I say will never see a plumber (or anyone else) do that.

I'd hazard to guess that they don't bother wearing seat belts when they drive either - same difference!

[chrisp]

Well....how often has this happened?
Would any plumber out there ever check if a pipe is electrified before cutting it?


Seriously...this is a freak accident.

Yep, it's a freak accident but they do happen. It is interesting to look at some of the statistics (which I haven't done for a few years!). IIRC, mechanics were the most likely to be killed by having a jack fail and have a car crush them; while the numbers are somewhat patchy, electricians seem to be the most likely to be electrocuted.

I suppose we all become complacent and can get caught out.

Anyway, please be careful out there!

[Muzza40]

There is another parallel path which should have saved him and that was the earth stake.

Older installations never had an earth stake. They used the copper water pipe bond as the main earth.
I know plenty of plumbers who have got tingles of pipes when they cut them and don't understand why. It's just not something many people immediately think about.

[mudbrick]

The jumper lead bridging the cut pipe is a great idea. Sure the jaws would be live but pose a much lower risk than the 2 ends of a cut pipe 3mm apart. I bet most plumbers carry one but rarely use it.
If the earth stake was going into dry ground the water pipe would have much lower resistance so carry most of the current.

[Spottiswoode]

I remember hearing about this year's ago, probably in an electrical safety course. It was not long after I had disconnected the water meter at home trying to fix a leak. Scared me a bit at the time, just hope that in the future I still remember it if I need to cut the 'circuit' again.

[PlatypusGardens]

......electricians seem to be the most likely to be electrocuted......

.....and I'm not surprised.


The amount of sparkies I've seen [s]play[/s] work with live wires hooking up a switch or GPO......

[PlatypusGardens]

Older installations never had an earth stake. They used the copper water pipe bond as the main earth.
I know plenty of plumbers who have got tingles of pipes when they cut them and don't understand why. It's just not something many people immediately think about.

I often get tingles from taps especially if I have a cut on my hands/fingers

[chrisp]

I often get tingles from taps especially if I have a cut on my hands/fingers

Check your equipotential bond. It's a wire that 'bonds' the plumbing to the electrical earth.

[Muzza40]

I'd be checking the neutral first.

[ringtail]

I'd hazard to guess that they don't bother wearing seat belts when they drive either - same difference!

Yep.

[ringtail]

Check your equipotential bond. It's a wire that 'bonds' the plumbing to the electrical earth.

Just re did mine a few months back. Copper pipe was painted and the clamp was also painted. Got my sparky to check and while he was there doing other stuff Polished up the pipe and clamp. Sparky rechecked before he left. All good and one less thing to worry about.

[PlatypusGardens]

Check your equipotential bond. It's a wire that 'bonds' the plumbing to the electrical earth.

Wasn't talking about my place specifically....more in general.
Seems to happen to me more than others too.

Guess I'm more....conductive than some

[Bros]

Wasn't talking about my place specifically....more in general.
Seems to happen to me more than others too.

Guess I'm more....conductive than some

Happens to me as well but only on a cut finger. The skin seems to act as an insulator compared to raw tissue. I have never measured it but I believe it would be very very low voltage. I would only expect that to happen in a slab on ground shower.

[Bros]

With the unfortunate incident rare though it is there were two faults that contributed to the fatality. Loss of neutral at the service pole (seen two of them)and lack of effective earth stake. The plumber could not have known this but I bet the householder did know there was a problem but couldn't explain it.

As for fitting a bridge around the cut seems fine in theory but you have to disconnect the clamp and if you disconnect the end that goes to the ground first the clamp is alive and how many clamps in a plumbers truck would be insulated. Doing the repair it could be a nuisance working around the bridge and its integrity could be comprised.

This incident is rare and I will be interested to see the coroners report for the full details.

[Saltypete]

Have been renovating off and on a few years now and will put my hand to most things. Know a good plumber and a good electrician. Do lots of the prep work for them, but I do what they say and pay their bills straight away. Sounds like I might be on to something.......