Abstract: An employee, the sole owner and operator, was trimming trees from a vehicle-mounted aerial lift at approximately 20 ft above the ground. A structural failure of the turret-boom connection occurred when the boom-supported bucket was repositioned to continue the tree-trimming activity. The complete rotating boom assembly separated from the truck-mounted turret and fell into the traveled portion of the street. The employee was partially thrown from the bucket, the back of his head impacted the asphalt street, and he died. In addition to a massive head injury, he received three right rib fractures at the sternum and two left rib fractures at the sternum. He was the previous owner of the machine involved and was working with the current owner, without an employer-employee relationship.