This handbook contains the rationale for Code requirements; explanations, examples, and illustrations of the implementations of the requirements; plus excerpts from other nationally recognized standards which are referenced by the Code. This information is intended to provide the users of the ASME A17.1 Code with a better understanding of, and appreciation for, the requirements contained in the Code. The net result should be increased safety for the manufacturers, installers, maintainers, consultants and users of the equipment covered by the ASME A17.1 Code. The commentary in this Handbook was compiled from A17 Committee minutes, correspondence, and interpretations, as well as conversations with past and present committee members.