Abstract: Employee #1 was using a capacity trailer spotting tractor truck, or trailer jockey, company #843 to off-load trailers from the San Juan barge. To unload the barge, drivers drove to the second level of a three-level concrete ramp that had an 11 in. high curb equipped with a metal guardrail. At each level of the ramp, there was an opening to the barge. Following company procedures, Employee #1 drove his truck to the edge of the second ramp so he could back up onto the barge and complete his final trip; however, Employee #1 accidentally backed the truck over the curb and through the guardrail. The truck fell 22 feet to the ground. Employee #1, who was not wearing a seat belt, was killed. The truck's brakes appeared to be in good condition, and the truck had operated without problems before the accident. Employee #1 may have thought that he had put the truck in reverse gear, or something may have been under the brake pedal that prevented him from depressing it.