EE WAS WORKING WITH ANOTHER EE ON A DRAG CHAIN. THEY WERE PUTTING A DRIVE CHAIN ON A SPROCKET WHEN HE FELT A PAIN IN HIS LOWER BACK. HIS BACK DID NOT HURT UNTIL THE WEEKEND. HE WENT TO THE DR. ON MON. 3/18 AND HE IS NOW ON RESTRICTED DUTY AND TAKING PHYSICAL THERAPY 3X A WEEK FOR 3 WEEKS.