Abstract: EMPLOYEES #1 THROUGH #6 WERE USING JACKHAMMERS, PICKS, SHOVELS AND A BOBCAT TO CLEAR METAL AND SLAG BLOCKAGE FROM A "SOAKING PIT" OPERATION AT A STEEL PIPE MILL. WHILE THEY WERE CLEARING THE PIT, A "SISTER" PIT ALSO BECAME BLOCKED. A "COKE BREEZE" USED IN THE SOAKING PROCESS IN THE SISTER PIT IS SUSPECTED OF EMITTING GASSES WHICH WOULD OTHERWISE HAVE BEEN VENTED AWAY FROM THE EMPLOYEES. INSTEAD, THE MIXTURE OF GASSES, INCLUDING SOME CARBON MONOXIDE, WAS DRAWN INTO THE AREA OCCUPIED BY THE 6 EMPLOYEES. THEY EXPERIENCED SYMPTOMS OF SHORTNESS OF BREATH, HEADACHE, DIZZINESS AND NAUSEA, BEFORE LEAVING THE AREA TO SEEK MEDICAL ASSISTANCE. THE EMPLOYEES HAD WORKED ALL MORNING WITHOUT ANY PROBLEMS. BEGINNING AT 12:15 AND CONTINUING UNTIL THEY QUIT AT 1:15, THEY BECAME ILL. THE DEVELOPMENT OF THEIR SYMPTOMS COINCIDED WITH THE OPENING AND CLOSING OF 2 SISTER PITS. CARBOXYHEMOGLOBIN LEVELS IN THE EMPLOYEES' BLOOD RANGED FROM 21.6% TO 36.1%, AS MEASURED BY THE LOCAL HOSPITAL. NO CARBON MONOXIDE ALARMS OR MONITORING EQUIPMENT WAS UTILIZED BY THE EMPLOYEES AT THE TIME OF THE EVENT.