Abstract: An apprentice power line worker and his supervisor were installing a new service from a utility pole near a street to a new weatherhead at a residence. They surveyed the area and walked the job to determine the length of conductor they would need to complete the job. After they strung the conductors, the apprentice went to connect the service conductors at the house while his supervisor was connecting the service conductors at the pole. To reach the weatherhead, the apprentice used an unsecured extension ladder that had previously been raised near the work area. The ladder had been extended to the roof, which was about 5.2 meters above the ground. The apprentice climbed the ladder onto the roof and connected the two line conductors and the neutral. He cleared the area of debris before descending. As he was getting on the ladder, it moved, and the worker fell. He sustained a shattered left elbow, a fractured left wrist, and a laceration to his left hand. He was hospitalized for his injuries for 3 days.