ENOGEX LLC

Incident Narrative

COMPRESSOR STATION WAS ISOLATED AND VENTED TO ATMOSPHERE FOR CONSTRUCTION TIE-INS RELATED TO EXPANSION PROJECT. A SHORT SECTION (APPROXIMATELY 12-18 INCHES) OF A 16 INCH RECYCLE PIPING SYSTEM WAS TO BE REMOVED AND A 16 X 8 REDUCING TEE ADDED TO CONNECT A NEW RECYCLE PIPING SYSTEM TO THE EXISTING RECYCLE PIPING SYSTEM. A LOCK-OUT/TAG-OUT PROCEDURE AND AN AIR MOVER WERE IN PLACE TO ELIMINATE OR MITIGATE HAZARDS DURING THE HOT WORK OPERATION. MEANWHILE, WORKERS WERE INSTALLING A NEW METER TUBE ON AN ADJACENT PIPING MANIFOLD THAT WAS CONNECTED TO THE RECYCLE PIPING SYSTEM. A 12"" BLIND FLANGE WAS REMOVED FROM THE PIPING MANIFOLD TO INSTALL AN ISOLATION VALVE BETWEEN THE NEW METER TUBE AND THE EXISTING PIPING MANIFOLD. A CONTRACT EMPLOYEE WAS STANDING BESIDE THE OPEN ENDED PIPE FLANGE AT THE SAME TIME THE NEARBY HOT WORK IGNITED VAPORS INSIDE THE PIPING SYSTEM. CONTRACT EMPLOYEE WAS INJURED AS A RESULT OF A FLASH FIRE WHICH IMMEDIATELY EXTINGUISHED ITSELF. CONTRACT EMPLOYEE'S INJURIES REQUIRED IN-PATIENT HOSPITALIZATION. UPDATE NOVEMBER 23, 2010 AN INVESTIGATION TEAM WAS ASSEMBLED IMMEDIATELY FOLLOWING THE INCIDENT AND AN INVESTIGATION WAS CONDUCTED TO DETERMINE THE CAUSE OR CAUSES OF THE INCIDENT. THE FOLLOWING CAUSAL FACTORS WERE IDENTIFIED: 1. TWO INDEPENDENT JOBS WERE ON-GOING AT THE SAME TIME WHICH IMPACTED ONE ANOTHER AND EFFECTIVE COMMUNICATION BETWEEN THESE JOBS WAS NOT ADEQUATE TO CONSIDER THE IMPACT OF INDEPENDENT ACTIONS TAKEN. 2. THREE VALVES (XV #853, XV # 861, AND XV # 871) FAILED OPEN WHEN THE INSTRUMENT AIR BLED OFF FOLLOWING THE INITIAL ESD. THIS CONDITION MAY HAVE UNKNOWINGLY INCREASED THE VOLUME OF VAPORS WITHIN THE PIPING REQUIRED TO BE PURGED PRIOR TO THE HOT WORK BEING CONDUCTED THEREBY DECREASING THE EFFECTIVENESS OF THE AIR MOVER. 3. A12-INCH BLIND FLANGE WAS REMOVED, POTENTIALLY CHANGING THE AIR FLOW DYNAMICS WITHIN THE PIPE AND POSSIBLY LIMITING THE EFFECTIVENESS OF THE AIR MOVER IN THE LOCATION OF THE 16-INCH TEE ON THE UPSTREAM SIDE OF THE EXISTING RECYCLE METER RUN. 4. THE SCOPE OF THE SAFE WORK PERMIT (WRITTEN PRIOR TO WORK BEING PERFORMED), WHICH INCLUDED MULTIPLE CONTRACTORS OVER AN ENTIRE SHIFT, WAS LIKELY TOO BROAD TO BE EFFECTIVE IN CONTROLLING MULTIPLE TASKS. THE FOLLOWING ROOT CAUSE(S) WERE IDENTIFIED: 1. THE POTENTIAL HAZARDS ASSOCIATED WITH MULTIPLE ONGOING AND SEEMINGLY UNRELATED JOBS WITHIN THE SAME GENERAL WORK AREA WERE NOT SUFFICIENTLY ANALYZED TO CONSIDER THE POTENTIAL IMPACTS OF ONE JOB ON THE OTHER. 2. THREE VALVES THAT WERE CLOSED DURING LO/TO FAILED OPEN DUE TO THE LOSS OF INSTRUMENT GAS AFTER THE ESD. THIS CONDITION WAS EITHER NOT ANTICIPATED OR NOT CONSIDERED TO BE RELEVANT DURING JOB PLANNING. 3. AN UNDETECTED FLAMMABLE ATMOSPHERE EXISTED WITHIN THE PIPING DURING AUTHORIZED HOT WORK ACTIVITIES. RECOMMENDATIONS ARE BEING IMPLEMENTED TO ADDRESS THE FINDINGS ABOVE TO PREVENT A RECURRENCE. UPDATE MARCH 5, 2013: COMPLETED SECTION E.5.F.