On Sun, 13 Sep 2009 18:29:02 -0400, "Ralph Mowery"
wrote:


"E Z Peaces" wrote in message
...
When humidity is low, clothing rubbing against car seats can cause static
shocks when a person touches grounded metal. If the car manufacturer puts
some megohms between that metal and ground, touching it will drain the
charge painlessly.

Actually the car metal does not have to be grounded. As the car is a large
mass of metal it will have a differance of potential from the person that
slides across the seat.
PUtting a resistor between the car and ground will do nothing for this
effect.

Not what the guy said. Put a resistor between the metal part you might
touch and the VEHICLE ground, and the likelihood of getting a static
shock can be reduced dramatically.

Years ago some gas trucks would drag a chain to ground the truck. This was
thought to drain off any static charge the truck would have so the gas would
not blow up when the hose was used to transfer the gas. A spark could jump
from the end of the hose to the storage tank.

When fueling aircraft the fuel tug (truck) MUST be grounded to the
plane before the fuel hose gets CLOSE to the plane.