EE WAS ADJUSTING A CONVEYOR BELT ON AN ELEVATED SAND SCREEN (VIBRATING) USING A 17"" BOXED-END WRENCH. THE WRENCH CAME OFF THE BOLT AND HIS FORWARD INERTIA CAUSED HIM TO LOSE HIS BALANCE, ALLOWING HIS LEFT ARM TO SLIDE UNDER THE BELT AND GO AROUND THE END PULLEY. THERE APPEARS TO BE A COMPOUND FRACTURE OF THE L. FOREARM PLUS ABRASIONS FROM THE L. SHOULDER TO THE L. HAND.