Abstract: At approximately 10:00 a.m. on November 14, 2001, Employee #1 was hooking a tow chain on the under side of the frame on the front of a water truck, the water truck, a CASE 9040-B excavator, was parked nearby. The operator of the excavator had exited the machinery, but left it running with its control levers in a non-operational position. Further, the control levers were not placed in a locked or safety position. Another coworker decided to enter the excavator to retrieve a tool. As he entered the machinery, he bumped the boom operating lever that engaged the boom. The boom extended moving with it an attached compacting wheel. The compact wheel struck Employee #1 pinning him against the front of the water truck. The compressive force of the compacting wheel and the front of the truck upon him resulted in serious injuries. These injuries included fractures to his back and seven ribs, punctures injuries to both lungs and damages to other internal injuries. It also damaged and removed large portions of skin on the employee's back. Employee #1 was hospitalized to receive medical care for the injuries sustained in the accident. The causal factors were that the excavator operator failed to safely secure the machine and operational controls prior to leaving the machinery.