Changing light bulbs on overhead signs

Missouri DOT’s policy is that when working over traffic from a man-lift or bucket type truck, the operator will position the bucket so any material/equipment dropped will fall within the basket. When working over traffic without such apparatuses (e.g., sign trusses/catwalks, DMS cabinets, etc.), the employee shall tether these items. If this is not possible, then the affected lane(s) of traffic shall be closed.
Note: In either case, the employee shall be outfitted in the proper fall arrest hardware.