Abstract: On September 10, 2003, an employee was affixing a numbered metal security band to the locking mechanism on the rear door of an outbound trailer. The trailer's locking mechanism was located on top of the trailer's rear door. The employee stated that he was on the top step of a mobile ladder stand positioned between two trailers. The trailers were attached to a tractor in the stop mode. The employee stated that the wheels or casters on the mobile ladder stand were in the locked position and the tractor's ignition keys were not in his possession. The tractor driver was outside of the tractor cab in view of the employee's stance. The employee stated that for reasons unknown to him, the tractor moved forward while he was on the platform of the mobile ladder stand. The employee stated that the mobile ladder stand started to fall over and he fell off the falling ladder to the paved surface. He sustained fracture to his right pelvis and was hospitalized.