EE WAS INSTALLING WATERLINE (4""PVC) TO HELP ADVANCE ONE END OF THE PIPE IN THE COUPLING. EE GRABBED THE OTHER END OF THE 20'SECTION, AS HE PUSHED ON THE PIPE TO SNAP IT TOGETHER, HE FELT PAIN IN HIS RIB CAGE AREA. HE CONTINUED TO WORK BUT THE PAIN GOT WORSE. ON 5/29/03 HE WENT BACK TO THE DR. X-RAYS SHOWED A COMPRESSION FRACTURE ON HIS 5TH & 6TH RIBS. STARTED MISSING ON 5/30/03.