B30.11 applies to underhung cranes and monorail systems where load-carrying members, such as end trucks or carriers (trolleys), travel either on the external or internal lower flange of a runway track section, single monrail track, crane bridge girder, or jib boom.
ASME B30.11 INT-1991 history
1970ASME B30.11 INT-1998 Interpretations to B30.11 - 1998 Monorails and Underhung Cranes