{"operation":"document","citation":"P-91-017","title":"NTSB Safety Recommendation P-91-017","source_type":"guidance","agency":"National Transportation Safety Board","status":"guidance","official":true,"published_on":"1991-08-06","effective_on":"1991-08-06","summary":"THE NTSB RECOMMENDS THAT THE NATIONAL ASSOCIATION OF REGU LATORY UTILITIES COMMISSIONERS: ENCOURAGE ITS MEMBER STATES TO REQUIRE THAT EACH GAS OPERATOR IMPLEMENT A PROGRAM, BASED ON FACTORS SUCH AS AGE, PIPE DIAMETER, OPERATING PRESSURE, SOIL CORROSIVENESS, EXISTING GRAPHITIC DAMAGE, LEAK HISTORY, BURIAL DEPTH, AND EXTERNAL LOADING, TO IDENTIFY AND REPLACE IN A PLANNED, TIMELY MANNER CAST-IRON PIPING SYSTEMS THAT MAY","machine_formats":{"json":"https://regulus.evalyn.ai/document/ntsb-recommendation-p-91-017.json","markdown":"https://regulus.evalyn.ai/document/ntsb-recommendation-p-91-017.md"},"app_url":"https://regulus.evalyn.ai/document/ntsb-recommendation-p-91-017","source_url":"https://data.ntsb.gov/carol-main-public/sr-details/P-91-017","body":"NTSB safety recommendation P-91-017.\n\nTHE NTSB RECOMMENDS THAT THE NATIONAL ASSOCIATION OF REGU LATORY UTILITIES COMMISSIONERS: ENCOURAGE ITS MEMBER STATES TO REQUIRE THAT EACH GAS OPERATOR IMPLEMENT A PROGRAM, BASED ON FACTORS SUCH AS AGE, PIPE DIAMETER, OPERATING PRESSURE, SOIL CORROSIVENESS, EXISTING GRAPHITIC DAMAGE, LEAK HISTORY, BURIAL DEPTH, AND EXTERNAL LOADING, TO IDENTIFY AND REPLACE IN A PLANNED, TIMELY MANNER CAST-IRON PIPING SYSTEMS THAT MAY THREATEN PUBLIC SAFETY.\n\nPriority: CLASS II\n\nOverall Status: Closed - Acceptable Alternate Action\n\nIssued Date: 1991-08-06\n\nAdopted Date: 1991-07-23\n\nOverall Date Closed: 1992-12-28\n\nSynopsis: ON 8/29/90, A NATURAL GAS EXPLOSION & FIRE DESTROYED TWO ROW HOUSES AT 421-423 NORTH FIFTH STREET & DAMAGED TWO ADJACENT HOUSES & THREE PARKED CARS IN ALLENTOWN, PA. ONE PERSON WAS KILLED, & NINE PEOPLE, INCLUDING TWO FIREFIGHTERS, WERE INJURED. THE NTSB'S INVESTIGATION DISCLOSED THAT WATER LEAKING FROM A CIRCUMFERENTIAL CRACK IN A 6-INCH CAST-IRON MUNICIPAL WATER MAIN BENEATH NORTH FIFTH STREET'S EAST SIDE HAD ERODED THE SOIL FOUNDATION OF A LOW PRESSURE (9 INCHES WATER COLUMN PRESSURE) 4-INCH CAST-IRON UGI CORPORATION (UGI) GAS MAIN BENEATH THE WEST SIDE OF NORTH FIFTH STREET. THE GAS MAIN SUBSEQUENTLY CRACKED CIRCUMFERENTIALLY AND NATURAL GAS FILLED THE VOID BENEATH THE PAVEMENT. NATURAL GAS THEN MIGRATED THROUGH THE SOIL & INTO THE BASEMENT OF 423 NORTH FIFTH STREET, WHERE IT IGNITED, EXPLODED, & BURNED. SUBSEQUENT METALLURGICAL EXAMINATIONS REVEALED THAT BOTH CAST-IRON MAINS WERE SIGNIFICANTLY WEAKENED BY GRAPHITIC CORROSION. THE WATER MAIN WAS INSTALLED IN THE LATE 1800S & THE GAS MAIN WAS INSTALLED IN 1903.\n\nProbable Cause: Undermined and weakened segment of cast-iron gas main\n\nNtsbnumber: DCA90FP011\n\nReport Number: PAB-91-01\n\nAddressee Name: National Association of Utility Commissioners\n\nAddressee Status: Closed - Acceptable Alternate Action\n\nAddressee Date Closed: 1992-12-28\n\nAddressee Acronym: NARUC\n\nAddressee Organization Type: A-Associations\n\nCommunication Date: 1992-12-28\n\nCommunication Type: Official Correspondence\n\nCommunication Contents: THE BOARD IS PLEASED TO LEARN, FROM RECENT CONVERSATIONS WITH NARUC STAFF, & AN AUGUST 16, 1991, LETTER FROM MR. PAUL RODGERS TO THE MEMBERS OF THE NARUC'S COMMITTEE ON GAS, THAT THE NARUC HAS INFORMED ITS MEMBERS OF THE CIRCUMSTANCES SURROUNDING THIS ACCIDENT BY PROVIDING A COPY OF THE BOARD'S RECOMMENDATION LETTER. WE UNDERSTAND THAT THIS IS AS MUCH AS YOUR ORGANIZATION CAN DO IN THE WAY OF ENCOURAGEMENT OF MEMBERS TOWARDS THE GOAL OF THE RECOMMENDATION. THEREFORE, RECOMMENDATION P-91-17 HAS BEEN CLASSIFIED \"CLOSED--ACCEPTABLE ALTERNATE ACTION.\"\n\nAddressee Acronym: NARUC\n\nAddressee Organization Type: A-Associations\n\nCommunication Date: 1991-08-16\n\nCommunication Type: Official Correspondence\n\nAddressee Acronym: NARUC\n\nAddressee Organization Type: A-Associations\n\nCommunication Date: 1992-10-30\n\nCommunication Type: Official Correspondence","truncated":false,"body_characters":2979}