本出版物由单轨制造商协会（Monorail Manufacturers Association，Inc.）编制，旨在帮助悬挂式起重机和单轨系统的制造商和用户。本规范最初于1973年被批准为MMA共识标准，并接受了ANSI Canvass审查程序，现在作为美国国家标准提供。它包括曲线、开关、转换装置、手推车、升降段的讨论。

This publication was developed by the Monorail Manufacturers Association, Inc. to assist manufacturers and users of underhung cranes and monorail systems. This specification was originally approved as an MMA consensus standard in 1973, was subjected to the ANSI Canvass Review Process, and is now available as an American National Standard. It includes discussion of curves, switches, transfer devices, trolleys, lift and drop sections.