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Safety Recommendation Details

Safety Recommendation P-71-007
Details
Synopsis: ON SEPTEMBER 9, 1969, A 14-INCH PIPELINE CARRYING NATURAL GAS AT A PRESSURE OF MORE THAN 780 P.S.I.G. RUPTURED IN A RESIDENTIAL SUBDIVISION 3 1/4 MILES NORTH OF HOUSTON, TEXAS. ALL RESIDENTS WERE EVACUATED, AND ABOUT 8 TO 10 MINUTES LATER, THE ESCAPING GAS EXPLODED VIOLENTLY. THIRTEEN HOUSES, RANGING FROM 24 FEET TO 250 FEET FROM THE RUPTURE, WERE DESTROYED BY THE BLAST. THE LEAKING GAS CAUGHT FIRE AND BURNED FOR 1 1/2 HOURS UNTIL VALVES ON EITHER SIDE OF THE LEAK WERE CLOSED BY MOBIL WORKMEN. IN ALL, 106 HOUSES WERE DAMAGED, AND PROPERTY DAMAGE WAS ESTIMATED AT $500,000. MIRACULOUSLY, THERE WERE NO DEATHS, BUT 9 PEOPLE WERE INJURED, 2 SERIOUSLY.
Recommendation: THE NTSB RECOMMENDS THAT THE OFFICE OF PIPELINE SAFETY OF THE DEPARTMENT OF TRANSPORTATION TAKE THE FOLLOWING ACTION: REVIEW THE METHODS USED BY PIPELINE OPERATORS TO PROTECT EXISTING TRANSMISSION LINES AGAINST ACCIDENTAL OVERPRESSURING UPON THE FAILURE OF PRESSURE CONTROL EQUIPMENT. THIS REVIEW SHOULD BE MADE IN CONJUNCTION WITH THE STATES. IF PROBLEM AREAS ARE DETECTED, ADEQUATE REGULATORY ACTION, INCLUDING RULEMAKING, SHOULD BE UNDERTAKEN TO ASSURE PROTECTION AGAINST OVERPRESSURING.
Original recommendation transmittal letter: PDF
Overall Status: Closed--No Longer Applicable
Mode: Pipeline
Location: Houston, TX, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: 80255
Accident Reports:
High Pressure Natural Gas Pipeline
Report #: PAR-71-01
Accident Date: 9/9/1969
Issue Date: 7/1/1971
Date Closed: 1/4/1990
Addressee(s) and Addressee Status: RSPA (Closed--No Longer Applicable)
Keyword(s):

Safety Recommendation History
From: NTSB
To: RSPA
Date: 1/4/1990
Response:

From: RSPA
To: NTSB
Date: 5/31/1989
Response:

From: NTSB
To: RSPA
Date: 9/11/1978
Response:

From: RSPA
To: NTSB
Date: 4/3/1978
Response: 2/24/72 - LTR FROM DOT: THE OFFICE OF PIPELINE SAFETY IS PLANNING A STUDY TO COVER THE RAPID SHUTDOWN OF FAILED FACILITIES, AND PRESSURE LIMITING ON OPERATING SYSTEMS. 10/2/72: DOT ISSUED THE REQUEST FOR PROPOSALS FOR THE STUDY. 11/4/77 - LETTER TO OPSO REQUESTING DOCUMENTATION OF STATUS OF PROPOSED STUDIES. 4/3/78 - OPSO LTR: A REVIEW WAS COMPLETED AS PART OF A STUDY "RAPID SHUTDOWN OF FAILED PIPELINE SYSTEMS AND LIMITING OF PRESSURE TO PREVENT PIPELINE FAILURE DUE TO OVERPRESSURE". THE FINAL REPORT HAS BEEN RECEIVED AND REVIEWED. THIS ALONG WITH ACCIDENT STATISTICS AND OTHER DATA, WILL PROVIDE A BASIS FOR NEW REGULATIONS FOR BOTH LIQUID AND GAS PIPELINES. NOTICES OF PROPOSED RULES FOR LIQUID SHOULD BE PUBLISHED IN FY-78. NO SCHEDULE AS YET FOR GAS PIPELINES. 7/7/78 - MTB LTR: OPSO CONTRACTED FOR STUDY "RAPID SHUTDOWN OF FAILED PIPELINE SYSTEMS AND LIMITING OF PRESSURE TO PREVENT PIPELINE FAILURE DUE TO OVERPRESSURE," WITH MECHANICS RESEARCH, INC. THIS STUDY INCLUDED A REVIEW OF PRESSURE CONTROL PRACTICES USED IN INDUSTRY. CONSIDERATION WAS GIVEN TO VARIOUS PRESSURE CONTROL DEVICES, THE EXTENT OF USE, RELIABILITY, VALUE IN REDUCING ACCIDENT EFFECTS, AND COSTS ASSOCIATED WITH THEIR USE. PROPOSALS ARE BEING DEVELOPED THAT INCLUDE ADDITIONAL REQUIREMENTS FOR OVERPRESSURING AND AUTOMATIC CONTROLS ON LIQUID PIPELINES. 10/30/78 - MTB LETTER: TWO NOTICES OF PROPOSED RULEMAKING, INVOLVING LIQUID PIPELINES, PUBLISHED IN FY 1978 - THE FIRST NOTICE PUBLISHED IN THE FEDERAL REGISTER ON AUGUST 10, 1978, PROPOSES TO ESTABLISH PROPER PROCEDURES THAT PIPELINE CARRIERS OF HAZARDOUS LIQUIDS MUST FOLLOW FOR HANDLING NORMAL OPERATIONS, ABNORMAL OPERATIONS AND EMERGENCIES; THE SECOND NOTICE PUBLISHED IN THE FEDERAL REGISTER ON SEPTEMBER 5, 1978, PROPOSES NEW REGULATIONS TO REDUCE THE AMOUNT OF LIQUID SPILLED IN ACCIDENTS INVOLVING PIPELINES CARRYING HIGHLY VOLATILE LIQUIDS IN INHABITED AREAS. THE EVALUATION OF THE COST EFFECTIVENESS OF PROTECTING EXISTING PIPELINES IS BEING CONDUCTED IN-HOUSE BY THE MTB WE PLAN TO EXPAND THIS EVALUATION TO INCLUDE EXISTING GAS PIPELINES. CORRESPONDENCE DOCUMENTATION INCOMPLETE.