On Mon, 28 Oct 2013 19:08:46 -0400, Wes Groleau
wrote:

On 10-28-2013, 08:45, Nate Nagel wrote:
I second the recommendation to just not touch the piping until the
problem is isolated. If OP has to take a shower I would check for
voltage on pipe with voltmeter and then turn off main breaker and verify
that issue has gone away. Yeah, you'll be taking a shower in the dark,

That's not quite good enough. Depends on HOW you check it. If you
check from right behind shower head to what you think ground and isn't,
then there might still be potential between sower and drain.

But you could detect no potential between shower and drain because drain
pipes are likely partly plastic. Yet if enough non-distilled water is
flowing, that can make the metal part at the end become a ground.

Second best way to check for something hot if you're not sure of the
return path is one of those things that work by proximity.
Unfortunately, many of those are tricky to adjust and can give false Hot
or false Not judgments if you don't know how to work them.

Best is to follow the advice already posted often: Call a pro.
The EASIEST way to test for a live chassis, or a live wire, is a neon
tester. It will light with only a "capacitive ground" and draws so
little current it is impossible to get a shock from.