Sets out recommendations for the design of rotating shafts, for cranes and hoists, which are subjected to torsional, bending and axial loads either singly or in combination, and to fixed shafts where the load rotates relative to the shaft. It does not cover shafts with a relatively large length between bearing supports to diameter relationship where stiffness becomes the limiting factor. Whilst This Standard refers specifically to electric motors as a power source, the method of shaft design applies equally well where other prime movers are used, provided the peak torque can be ascertained (eg. with steam engines this would be appreciably higher than the average torque developed at full load.