I know that if my hands are dry, I can't feel 50 volts at all.
Let a little sweat start to roll and it is a different story.  While somebody
with a weak heart might need to worry about the electricity, the other
real possibility is that someone might flinch at the shock and hit their
hand on something which could either break or may already be sharp and cut
their skin.  This may sound a little far-fetched, but one would be surprised
how easy it is for something like that to happen.

        Our house used to have the old hard-wired telephone service.  When
I ran some extra extensions, I always hated the little nips I used to get
while handling the wires with sweaty hands under our house.  Even taking a
telephone off the hook to prevent somebody from calling us and ringing
my hand did not prevent being able to feel the DC on the live pair.

        Fifty volts exposed where it could be easily touched is pushing
one's luck a bit.

Martin McCormick WB5AGZ  Stillwater, OK 36.7N97.4W  in Tornado Ally
OSU Center for Computing and Information Services Data Communications Group