hmm... good question.
There are several dynamics to falling from a set amount of height. The higher, and this is ironic, the better chances of survival - to an extent.
Compare, if you will, a three floor fall to a 6 floor fall. It's been proven from accident statistics that the 6 floor fall is survivable more so than that of a three floor fall because of velocity, impact placement and spreading of impact throughout the body.
The human body is a strange creature indeed, it's amazing how much torture and impact it actually can spread across the frame of both skeletal and muscular persuasion. For instance, take hitting water at a 3 floor height compared to soil...water is like concrete at that height, you can break bones with water more so than you would with soil.
The dispersement of the impact depends on the landing position as well - flat on back, side or stomach? Flat on back with hands and feet spread out is actually safer than side or stomach, especially with the chin tucked forward to prevent the head from slamming on the ground.
It seems, from studies I've seen, that most falls recorded end up with a back landing and on soil or grass rather than concrete or water. I've also seen it said that if you land in water feet first you are likely to shatter shin bones and possibly not so much walk away without multiple fractures of the legs and hips - again water is like concrete theory at play here again.
There's also the other side of the equation - higher falls such as 10 and 12 floor falls can cause internal organ implosions resulting in nearly immediate death through organ failure and internal bleeding. Either way, falls of any height higher than 1 to 2 floors would result in a need for medical attention of the immediate kind.