HANDLING OF MATERIALS at Essroc Cement Corp
Employee was pulling a 4"" corrugated plastic pipe with a blunt end steel pipe attached to the end across a catwalk with floor grating. The pipe was caught on the floor grating, and when he pulled it towards himself it jumped, and he was expecting more resistance, but the pipe came back hard, and hit himself with the pipe in the goin (scrotum) area.
U.S. Mine Safety and Health Administration