Abstract: At approximately 8:45 p.m. on December 27, 1996, Employee #1, of California United Terminal, and three coworkers were in the yard unloading Caterpillar tractors from a rail car. They had removed one tractor from the rail car and were preparing to start on the second tractor when the crew noticed some packing under the tractor. Under the nighttime illumination, they could not identify what it was; later, it was discovered to be heavy steel counterbalances. A coworker was starting to drive the second tractor off the top of the boxcar when a counterweight flew off and struck Employee #1 on the leg as he stood on the ground approximately 15 ft from the rail car. He was taken to St. Mary's Hospital in Long Beach, CA, where he was admitted for a fractured leg. The material being off loaded was not secured from falling off the car and there was no check that the floor of the rail car was in a safe working condition. As it turned out, the steel counterweights had been packed by the employer.