EE WAS OBSERVING A MECHANIC WORK. MECHANIC WAS USING A 16 LB SLEDGE HAMMER & THE HEAD CAME OFF, STRIKING EE ON THE TOP LEFT EDGE OF HIS FOOT. HE WAS TRANSPORTED TO THE MEDICAL CENTER FOR EVALU ATION & TREATMENT. HIS FOOT WAS X-RAYED & A FRACTURE WAS FOUND. EE WAS REFERRED TO AN ORTHOPEDIST, & RELEASED TO RESTRICTED DUTY.