Two employees were working on a rig floor, separating the connection on a drill pipe. As they were starting to push the stand of the pipe, one employee slipped in some oil-based mud on the rig floor, fell forward, and put his hands out in front of himself to minimize the fall. The drill pipe moved back slightly and pinched his fingertip against the rig floor, resulting in the amputation of his right index fingertip above the first knuckle.