It is well known that falls from height still remain the single biggest cause of fatalities on site and in the workplace. The force of gravity means that we accelerate earthwards at 32 feet/second/second and the force we hit the ground with increases very rapidly with height.
The factors involved are the force of gravity, the height of the fall, the weight of the individual and just how much the fall is cushioned on impact. This means that the greater the height, the heavier the individual and the less yielding the surface, the greater the force of impact.
A fall from one metre doesn’t sound much, but dropping as a dead weight, an 80kg man could encounter a force of 100g if falling onto concrete.