An employee was attempting to lift a metal grate off of a burn table for cleaning purposes. Using a two-hook chain sling, the employee used one of the hooks with the other being left to dangle. The other hook got caught under the frame of the burn table. When the employee went to lift the grate, the hook that was unknowingly caught came free, flying across and striking the employee in the face. The employee suffered contusions to the face, nose, left cheek, and right forehead.