This standard establishes the minimum proportion between the winding diameters of drums and pulleys with respect to the nominal diameter of the cable for lifting and boom hoisting operations. The nominal diameter of the cable will be considered as a base factor when applying the ratio. The use of this nominal diameter allows flexibility of application since it is not limited to crane mechanisms; Mobile cranes are generally built for multiple uses, such as hook, grab or electromagnet lifting. This standard applies to the base types of self-propelled mobile cranes defined in UNE 58-502.