Gregg Martell wrote:
> Trenches can be very dangerous - dirt weighs over 100 lbs per cubic
> foot, so a cave-in in even a shallow trench can be deadly. If you
> are over your head in a hole that isn't properly prepared/shored you
> are taking your life in hand.
As it mentions on that site, even a cave-in up to your
diaphragm/belly-button area can be
lethal. If you can't move your diaphragm, you can't inhale.....
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