A Top Running Single Girder bridge crane is the most common type of overhead bridge crane. It is a versatile bridge crane that can be utilized for a wide variety of industries. cranes can be built with capacities up to 15 ton and spans up to 98 ft.  Typically, crane capacities vary between 5 and 10 ton.  With these capacities, the bridge beam is typically a wide flange structural member.  Most cranes that exceed a capacity of 10 ton with a span greater than 60 ft will utilize a box girder bridge beam.

The hoist/trolley used on a crane is always an under hung style trolley which runs on the bottom flange of the bridge beam.  For this reason, a crane is not the best crane option if facility headroom is a major issue.  

Top Running Single Girder bridge cranes use end trucks that operate on ASCE rail or square bar that is attached to the top of the runway beam.  The runway for a crane can either be building supported (if building is suitable) or by using a freestanding runway system.  The runway beams generally span across a full building bay.  One downside to any top running bridge crane is that the hoist/trolley is not able to travel beyond the runway, limiting the hook coverage area of the hoist/trolley.  See Under Hung Single and Double Girder cranes if maximum hook coverage is required.