On Sunday, 29 May 2016 10:37:25 UTC+1, Rod Speed wrote:
Obviously a 5 volt low current supply isn't usually life threatening.

Never is in fact.

It could be quite unpleasant if the water has bath salts added
to improve conductivity and you have wet hands.

USB chargers are not low current. However, it is difficult to
think of a scenario where the 5V would be applied across your body.

I once had an unpleasant shock from a 9V battery when standing
in sea water. I was changing the batteries in a hydrophone
preamplifier at the time.

John