Abstract: At approximately 7:15 a.m. on July 13, 1989, Employee #1 was doing finish nailing on plywood side panels on a one-story building. He was using a pneumatic nail gun working from an 8 foot stepladder. Employee #1 laid the nail gun down on the painter's platform on the ladder and began to descend to get more nails. The nail gun fell from the platform. Employee #1 attempted to catch the nail gun, caught the trigger handle, and accidentally depressed the trigger. The head of the nail gun hit Employee #1 in the upper left portion of his chest and discharged a 3 inch nail into his chest. Employee #1 sustained a puncture wound to his chest and the upper edge of his left lung.