Abstract: At approximately 10:00 a.m. on July 23, 1993, a 140 ton P&H mobile wire rope-operated rubber truck crane, model #9124ATC, serial #32883, while set in place on extended outriggers, was in the process of hoisting and placing a pre-cast concrete double tee beam for a parking garage in the process of being erected. The beam was approximately 60 ft long by 10 ft wide and weighed a stated 41,948 lb. The lift was off a trailer placed at the front bumper (the front outrigger was set with 30,000 lb bumper weight in place), and was a counterclockwise swing to the rear right end of the crane. While the load was being swung over the left front outrigger, the crane tipped forward. At the same time, the operator heard a noise. The crane operator swung the load away from the building and was lowering it to the ground when it struck another tee beam loaded on a trailer, sliding along its edge. The outer end struck the tractor attached to the trailer. Employee #1, an owner-operator truck driver who was inside the tractor cab, sustained minor cuts and bruises to his right arm and elbow. An investigation revealed that the crane was not set up in accordance with manufacturer's specifications; that the crane had been overloaded on the two previous lifts; and that soft unstable ground conditions existed. Additionally, there were depressions under the steel pads used to distribute weight on the asphalt parking lot surface, and a major depression was noted under the left front outrigger pad position. The employees responsible for crane placement and load management, who had approximately 20 years experience, were not using the correct load chart for this crane, and were not trained in load chart calculations for radius and deductions. No competent personal inspections were regularly performed, and non-accident-related defects were noted. The crane operator, who had approximately 33 years experience, was not involved in load management or crane placement. The employer had no crane safety and health program, although it is an erection company that uses cranes extensively.