Breaking strength is more commonly known as tensile strength. It is defined as the point at which certain materials will become deformed or break under a given load. The point at which the material comes to breaking strength is described as necking.
Method of finding the Safe Working Load (S.W.L) is to divide the Breaking Strength by factor of safety. The following factors of safety for ropes are used generally:
Lifts and hoist – 12 Running rigging and slings – 8 Other purposes – 6
Safe Working Load = Breaking Strength / Safety Factor