Volume B30.17 includes provisions that apply to the construction, installation, operation, inspection, and maintenance of hand-operated and power-driven overhead and gantry cranes that have a top-running single-girder bridge, with one or more underhung hoists (see B30.16 Volume)operating on the lower flange of the bridge girder, used for vertical lifting and lowering of freely suspended, unguided loads (see Figs. 1 through 5). The requirements included in this volume also apply to cranes having the same fundamental characteristics such as polar gantry cranes, cantilever gantry cranes, semi-gantry cranes, and wall cranes. Requirements for a crane used for a special purpose such as, but not limited to, non-vertical lifting service, lifting a guided load, or lifting personnel are not included in this volume.