Thread: Lightning
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Peter
 
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Tinkerntom wrote:
Brian, I live here in Denver, the High Plains, and called the
lightening capitol. I have heard about squatting on your mat for
insulation, and personally I think that rates up there with "duck and
cover". You are in the correct position to bend over and Kiss your Ass
goodbye! Lightening after it has traveled through 20 - 50 miles of
atmosphere does and goes where lightening wants, and a half inch of
foam padding is not going to make much difference, unless it makes you
feel more comfortable.


There are two reasons for the insulating mat. The first is not to stop
the lightning discharge once it has started, but to help make you a less
attractive target so the lightning is less likely to "want" to go there.

When the clouds overhead pass by with their electrical charge, they
attract the opposite charges in the ground which then travel up anything
elevated and start discharging into the air. This is why people in the
middle of lightning storms sometimes report feeling their hair standing
on end as the charges discharge from the strands of hair - and is a good
indication that you're in a very unsafe spot. Even a little insulation
can greatly reduce the amount of charge that can enter your body from
the ground during this period preceding the lightning strike and can
help make you a less attractive target than some tree or bush that is in
better electrical contact with the ground and is therefore concentrating
a large charge opposite (and therefore attractive) to that of the clouds.

The second, and probably more important, benefit of the mat comes in the
event that lightning does hit somewhere near you. In that case
electrical currents will flow outward through the surface of the ground
and any two points on the ground will have a voltage difference given by
the current flow times the resistance of the ground between those points
(Ohm's law). Keeping your contact points with the ground (or mat) close
together as you do in a squat is therefore recommended since it
minimizes that voltage difference. At this point the insulating mat
results in making the ground the path of least resistance so the current
tends to flow under you rather than up through your body. You don't
want your hands or any part of your upper body to be contacting the
ground (or mat) so any current that does still flow through you only
goes between your legs and doesn't pass through your heart.