The ground or structure have to can sustaining the weight of the scaffold and any kind of loads likely to be put on it. http://18364.users.rrmail1.com/go/iRlY.Zl9np.fz75.1z1Lvb/?aHR0cHM6Ly93d3cuZGVybWFuZGFyLmNvbS91c2VyL2NoYW5jZWNsYXZlOS8=