An employee was using a hoist to move a roll of mat facing into place above a conveyor. The roll was attached to the hoist with a hook that cradles a mandrel bar that passes through the core of the roll. While lowering the roll, one side of the roll contacted a fall protection railing. The employee then began to readjust the roll's position using the hoist pendant control while simultaneously guiding the suspended load with his left hand. The collar on the mandrel bar dislodged and the roll began to tilt and fall toward the conveyor. The mandrel bar closest to the employee swung up and pinched their left ring fingertip against the lifting hook resulting in partial amputation of the distal phalanx.