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RE Just a slight buzz or what

Since we have been discussing GFCIs lately I thought the following info
might be interesting.  Here's some info on amps (on house circuits) and
how humans typically react when exposed:

A mere 5 milliamps (mA) is considered the maximum current that is
normally completely harmless to humans.  5 mA is the level at which
some GFCIs, (such as Levitons), trip.  But 5 mA can sometimes still be
felt. Actual pain begins at about 8 mA.  Good news is you can still
release your grip up to 15 mA. Bad news is more than 10 mA is serious.

Just 200 mA, and sometimes as little as 60 mA, for more than one
second, can cause ventricular fibrillation -- that's not just a buzzm,
that's often fatal. Higher than 200 mA, well you get the idea.

Of course a lot depends on the path through your body.  If the path is
through your heart (e.g., in one hand and out the other), that's more
likely to be harmful than other paths (e.g., in one hand and out the
same hand).  And the frequency can be a factor too -- since AC tends to
flow on the outer surface of a conductor, a very high frequency shock
to your body will tend to flow on your skin and not through your
organs.  Tesla used to use this fact to put some pretty strong jolts
through (actually over) his body.  But at house current frequencies,
60Hz, don't expect the skin effect to save you. If you don't have
GFCIs, turn stuff off before dipping your hand into the water.

Scott H.

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