An employee was welding a bed plate (an L shaped attachment) to lift a steel I-beam from the floor onto several horses approximately 36" high. The I-beam, with the bed plate attachment, weighed approximately 1,500 lbs. The employee was using a remote operated overhead bridge crane to maneuver the beam. A single chain from the overhead trolley was used to lift the I-beam and at the end of the chain was a steel J hook. A one-ton clamp was hooked on the J hook. The clamp was then affixed to the bed plate of the I-beam. As the beam was lifted, the employee was using his left hand to guide the beam when the beam slipped from the clamp and fell approximately three feet to the ground. The employee's left hand was caught under the beam and the left index, middle, and ring fingers were amputated.