Abstract: On January 25, 2003, Employee #1, an apprentice, was in training to become a roofer. This was his first day on the job, which was a re-roofing project. There were a total of three people onsite, which included Employee #1, his supervisor, and a coworker. The shingles and tar paper had already been removed and all three employees were located on the roof, installing the skip sheeting (1-inch by 6-inch boards with about an 8-inch gap between them). For some reason, Employee #1 slipped and his left leg fell between the sheeting, twisting his right leg. Employee #1 dislocated his right knee cap. Employee #1 was hospitalized and treated for his injury.