I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

A current of 3.5 to 4.0 milliamps is not usually felt, but can spoof the
ICD, which looks for such signals lasting about 300 milliseconds.

This would be easy to check with a voltmeter. And to prevent by
running a ground wire from showerhead to drain pipe.

Joe Gwinn

"Joseph Gwinn" wrote: clip) This would be easy to check with a voltmeter.
And to prevent by
running a ground wire from showerhead to drain pipe.
^^^^^^^^^^^^^^^^^^^^^
I wouldn't hesitate to run a ground wire as a temporary fix, but how do we
know it will carry only 4 or 5 mils? It will carry current 24/7--I would
try to figure out how line voltage is getting to the shower head, and fix
that.

Joseph Gwinn wrote:
I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

A current of 3.5 to 4.0 milliamps is not usually felt, but can spoof the
ICD, which looks for such signals lasting about 300 milliseconds.

This would be easy to check with a voltmeter. And to prevent by
running a ground wire from showerhead to drain pipe.

Joe Gwinn

IIRC in the UK all runs of conductive pipe, typically copper in my
experience, have to be earthed to prevent this sort of thing. Having
said that I do know a guy that did some DIY and had a section of plastic
pipe joining 2 copper piping systems in his house which left one section
unearthed and this situation arose where the unearthed section became
live, luckily no one was injured just s few minor shocks.

Joseph Gwinn writes:

I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

I suspect it was a point-of-use waterheater in the head. Unknown
in the US; they are seen elsewhere.



--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

"David Lesher" wrote in message
...
Joseph Gwinn writes:

I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

I suspect it was a point-of-use waterheater in the head. Unknown
in the US; they are seen elsewhere.





I have seen them in Costa Rica. So they are in the West.

Reading some of the replies - I have this to add.

Hot water lines are very often isolated from the tank to prevent
current leakage by dissimilar metals which can eat a tank up.

This isolation can be the issue - if the pipe doesn't dive under a
concrete slab or underground.

Remember many places have only air and brackets. Think non-1 family house.

Wire running a length along a pipe - in a race way - it being a single wire
e.g. one line of a 220 going to a heater... The other wire is there but
not as neat..

The wire induces current in the water pipe and the nominal voltage drop
drives a nominal current in the water stream.

Martin

Joseph Gwinn wrote:
I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

A current of 3.5 to 4.0 milliamps is not usually felt, but can spoof the
ICD, which looks for such signals lasting about 300 milliseconds.

This would be easy to check with a voltmeter. And to prevent by
running a ground wire from showerhead to drain pipe.

Joe Gwinn

In article ,
"Leo Lichtman" wrote:

"Joseph Gwinn" wrote: clip)
This would be easy to check with a voltmeter.
And to prevent by
running a ground wire from showerhead to drain pipe.
^^^^^^^^^^^^^^^^^^^^^
I wouldn't hesitate to run a ground wire as a temporary fix, but how do we
know it will carry only 4 or 5 mils? It will carry current 24/7--I would
try to figure out how line voltage is getting to the shower head, and fix
that.

Belt and suspenders.

Joe Gwinn

In article ,
David Billington wrote:

Joseph Gwinn wrote:
I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

A current of 3.5 to 4.0 milliamps is not usually felt, but can spoof the
ICD, which looks for such signals lasting about 300 milliseconds.

This would be easy to check with a voltmeter. And to prevent by
running a ground wire from showerhead to drain pipe.

Joe Gwinn

IIRC in the UK all runs of conductive pipe, typically copper in my
experience, have to be earthed to prevent this sort of thing. Having
said that I do know a guy that did some DIY and had a section of plastic
pipe joining 2 copper piping systems in his house which left one section
unearthed and this situation arose where the unearthed section became
live, luckily no one was injured just s few minor shocks.

I've run into a parallel in the US, in the 1970s. Friends complained
that the sink in the bathroom off the kitchen generated sparks when
used. I didn't believe it, but they persisted, so I came over one day,
voltmeter in hand. Turns out there was 110 volts between water valve
and drain, with plenty of power. No idea why nobody was hurt. This
should have cooked the grease out of some luckless soul. Turned out
that the plumbers had broken a kitchen-light wire while installing the
2nd-floor bathroom drain, and the broken wire was resting on the copper
drainpipe, which was isolated from ground by an oakum&lead connection to
cast iron pipe.

I forgot to mention, but there is a RCM issue here as well. Old
machines are often leaky electrically, and so the frame of all machines
should be firmly grounded. There was a thread about this, but I don't
recall date of title (which may be unrelated). Anyway, I'd use the
voltmeter between cold-water ground and machine frames, with machines
running, to verify that the ground works.

Joe Gwinn

On Tue, 14 Apr 2009 10:27:09 -0400, Joseph Gwinn
wrote:

I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

A current of 3.5 to 4.0 milliamps is not usually felt, but can spoof the
ICD, which looks for such signals lasting about 300 milliseconds.

This would be easy to check with a voltmeter. And to prevent by
running a ground wire from showerhead to drain pipe.

I've seen it and fixed it. No ICD triggers, but the sensitive
people felt it in the shower and complained. Took me a while to track
it down.

Combinations of idiocy. They had an open Neutral wire and a
faked-in Neutral wire headed out to the wellhead. 2 HP submersible.

Now this wouldn't be a problem normally, since the well is 240V and
only time there would be a load on the Neutral is when they were
working on the well and wanted to use 120V power tools or a light.

But then they tapped off the well for 120V lights and appliances on
a semi-permanent residence tent - they saw a white wire and figured
they were solid.... And all the unbalanced Neutral current was going
through the water to find a ground, and made it up the water line all
the way to the shower heads in the permanent building.

Had to re-pull the power lines (including fresh Neutral and Ground)
all the way out to the well, and of course the problem vanished.

-- Bruce --

On Tue, 14 Apr 2009 10:27:09 -0400, Joseph Gwinn
wrote:

I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

A current of 3.5 to 4.0 milliamps is not usually felt, but can spoof the
ICD, which looks for such signals lasting about 300 milliseconds.

This would be easy to check with a voltmeter. And to prevent by
running a ground wire from showerhead to drain pipe.

Joe Gwinn

I couldn't get much from the website. Who made the ICD in question,
please?

On Apr 14, 6:55*am, David Lesher wrote:
Joseph Gwinn writes:
I saw this article in The New England Journal of Medicine. *Here is the
URL, unfortunately behind a paywall. *
http://content.nejm.org/cgi/content/short/360/13/1363
The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain. *

I suspect it was a point-of-use waterheater in the head. Unknown
in the US; they are seen elsewhere.

--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

They have them here in the US. They're just not well known.
Karl

In article ,
Don Foreman wrote:

On Tue, 14 Apr 2009 10:27:09 -0400, Joseph Gwinn
wrote:

I saw this article in The New England Journal of Medicine. Here is the
URL, unfortunately behind a paywall.

http://content.nejm.org/cgi/content/short/360/13/1363

The gist is that a danish doctor had a patient who was getting
inappropriate cardiac shocks from an ICD (implantable cardioverter-
defibrillator) while in the shower, which turned out to be due to bad
house wiring causing a 50 Hz leakage current from showerhead to floor
drain.

A current of 3.5 to 4.0 milliamps is not usually felt, but can spoof the
ICD, which looks for such signals lasting about 300 milliseconds.

This would be easy to check with a voltmeter. And to prevent by
running a ground wire from showerhead to drain pipe.

Joe Gwinn

I couldn't get much from the website. Who made the ICD in question,
please?

They didn't mention any makes or models. They implied that the problem
is general.

Joe Gwinn