EE WAS ATTEMPTING TO LOOSEN A BOLT ON A PUMP FLANGE. THE BOLT LOOSENED SUDDENLY AND THE EE'S HAND SLIPPED, STRIKING THE END OF A 1/4"" BOLT PROTRUDING FROM THE PUMP MOUNTING BRACKET. THE EE STRUCK THE BACK OF HIS RIGHT HAND, BRUISING IT AND CAUSING A SMALL PUNCTURE WOUND.