Abstract: AT APPROXIMATELY 4 PM ON AUGUST 20, 1985, A PRESSURE BUILDUP IN THE REACTOR IN BUILDING NUMBER 14 CAUSED A SAFETY VALVE TO RUPTURE. THE REACTOR, WHICH CONTAINED BISPHENOL A (BPA) AND PHOSGENE GAS, VENTED THROUGHT THE SAFETY VALVE AND INTO LINES LEADING TO AN EMERGENCY SCRUBBER. THE PHOSGENE GAS LEAKED AROUND SOME LOOSE BOLTS IN A FLANGE ON THE LINE LEADING TO THE SCRUBBER. CONTRACTOR PERSONNEL WHO HAD WORKED ON THE LINE A FEW WEEKS AGO HAD NOT ADEQUATELY TIGHTENED THE FLANGE BOLTS. FIVE EMPLOYEES WERE EXPOSED TO THE LEAKING PHOSGENE GAS. EMPLOYEE #1 WAS ON HIS WAY TO BUILDING 45 TO QUIT WORK FOR THE DAY. HE WAS PROCEEDING ALONG THE EAST SIDE OF BUILDING 14 TO WARN OTHER EMPLOYEES TO EVACUATE THE AREA. EMPLOYEE #2 DROVE A VEHICLE THROUGH THE PHOSGENE CLOUD AND THEN ALONG THE EAST SIDE OF BUILDING 14 TO ANOTHER PART OF THE PLANT. EMPLOYEES #3 AND #4 WERE LOCATED ALONG THE EAST SIDE OF BUILDING 14, CLEANING A SEWER LINE. EMPLOYEE #5 WAS LOCATED AT THE SOUTH DOCK OF BUILDING 14, PUTTING HIS TOOLS AWAY AND QUITTING WORK FOR THE DAY. ALL FIVE EMPLOYEES WERE KEPT OVERNIGHT AT THE PLANT'S MEDICAL FACILITY AND OBSERVED BY THE PLANT'S PHYSICIAN. THE FIVE EMPLOYEES SUSTAINED NO INJURIES OR ILLNESSES AS A RESULT OF THEIR EXPOSURE TO PHOSGENE GAS.