Abstract: At approximately 12:00 p.m. on June 9, 2011, Employee #1 and three of his coworkers were working for their employer, the San Francisco Municipal Transportation Agency, in the shop area of the Overhead Lines Department. At that facility, overhead trolley wires, guy wires, and poles were typically maintained. Related work was done for light rail and bus service, including the electric lines. Employee #1 and his coworkers were winding a 1.75-inch Samson rope, which had been removed from Truck Number 15, onto the winch drum of Truck Number 960. Truck Number 960 had been pulled up through the east side rollup door and was parked near the center of the east end of the shop, in line with the rollup door entrance. The boom was rotated out 90 degrees from the axis of the truck, with the winch line extended to the opposite end (west end) of the shop and hooked onto Truck Number 20 to maintain tension. In order to properly wind the rope onto the drum, it was necessary to maintain tension on the rope, between the hook end and the drum end of the boom. Employee #1 was standing on Truck Number 960, adjacent to the boom. A coworker operating the winch was sitting in the seat adjacent to the boom and operating panel for the winch, on the opposite side of the boom from Employee #1. A second coworker was sitting in Truck Number 20, steering and braking with the vehicle in neutral. The third coworker, the supervisor, was walking alongside Truck Number 20 to oversee the operation, as the winch from Truck Number 960 reeled in the approximately 150-foot-long Samson rope. With all but the last 30 feet of rope reeled in, Employee #1 was attempting to guide the rope onto the drum, so that the rope did not overbite and bury itself. Because the boom was rotated 90 degrees, Employee #1 had to reach out and around the left side of the drum to guide the rope. The winding rope was traveling towards Employee #1, and the drum was between his hand and body. The rope became hung up on the metal ridge adjacent to the drum, and Employee #1 intended to hit the rope with his hand to free it. Before he could do that, the rope jumped, caught his left index finger, and pulled it towards the drum. The rope rolled over itself and pinched Employee #1's left index finger between it and the drum. Employee #1's left index tip was amputated. The winch operator stopped the winch, and Employee #1 pulled his hand out. Employee #1 was hospitalized. The employer reported the serious injury to the Division on the same day that it occurred.