(Sorry in advance)
From the maker of How many people would have to be killed to make the streets 'run red with blood'? we have yet another question about dead bodies and how to use them.
In effect, say we have a 10 x 10 foot room (3.05 x 3.05 in meters). How many skeletons would have to be demolished to produce a covering 0.5 inches (1.27 centimeters) thick of powder over the floor that you could leave a footprint in?
Assume an airtight room and no bone pieces are ever lost or removed from the room. Assume the bones of a person were crushed or burned- whichever produces more 'debris'. Assume no blood, flesh, or anything other than pure bones is destroyed to make this inch of powder.