ABSTRACT
EVERY component of a lifting apparatus has an ultimate stress at which it will fracture and a safe stress at which it can normally be used. This latter is called the safe working load (S.W.L.). Every component has this S.W.L. stamped or painted upon it-in the case of wire or chain it is either stamped on a durable tablet attached to the material or else a notice is posted in a conspicuous place in the working vicinity where employees can refer to the safe working loads of all ropes, wires, and chains in use.
