EE WAS ATTEMPTING TO LOOSEN THE BOLT ON THE TRAINING CLAMP THAT HOLDS THE CONVEYOR CHAIN-ADJUSTING BOLT. HE WAS USING A 1/2"" RATCHET WITH A SHORT EXTENSION PIPE. AS TORQUE WAS APPLIED, THE RAT CHET GEARS SLIPPED INTERNALLY CAUSING EE'S RIGHTLEG TO FLEX AND BODY WEIGHT TO SHIFT SUDDENLY. THIS ACTION CREATED PAIN IN EE'S RT. ANKLE AND UPPER LEG.