Abstract: At approximately 12:30 a.m. on October 22, 1990, Employee #1 was operating a Bobcat model 742 loader, serial #501945210, at the construction site of a single family house. A drain tile pipe was being installed at the bottom of the house's foundation. A 5 ft wide and 5 ft deep excavation was around the perimeter of the foundation. Employee #1 was transporting stone with the Bobcat and dumping it into the excavation to cover the drain tile. While he was maneuvering away from the edge of the excavation, the Bobcat started to sink in the soft soil and then fell upside down into the excavation. Employee #1, an experienced Bobcat operator, had the seat bar in the down position; however, he did not use the installed safety seat belt as recommended by the manufacturer in the operator's handbook. He was injured and required hospitalization.