NTSB Safety Recommendation P-75-007

NTSB safety recommendation P-75-007.

INITIATE A STUDY, IN COOPERATION WITH THE AMERICAN GAS ASSOCIATION (AGA) AND OTHER INTERESTED GROUPS, OF THE EFFECTS ON AUTOMATIC LINE VALVE OPERATION OF OPEN VERSUS CLOSED CROSSOVER VALVES ON LOOPED NATURAL GAS TRANSMISSION SYSTEMS, AND AMEND 49 CFR 192.179, TRANSMISSION LINE VALVES, TO INCORPORATE THE FINDINGS.

Priority: CLASS II

Overall Status: Closed - Unacceptable Action

Issued Date: 1975-05-28

Adopted Date: 1975-05-28

Overall Date Closed: 1988-09-29

Synopsis: ON JUNE 9, 1974, THE TRANSCONTINENTAL GAS PIPE LINE CORPORATION'S 30-INCH NATURAL GAS TRANSMISSION PIPELINE RUPTURED IN A RURAL AREA NEAR BEALETON, VIRGINIA. NATURAL GAS ESCAPED, IGNITED, AND FUELED FLAMES WHICH WERE VISIBLE TO AIRLINE PILOTS OVER 100 MILES AWAY. NO DEATHS OR INJURIES RESULTED, NO LIVESTOCK WERE AFFECTED, AND PROPERTY DAMAGE AMOUNTED ONLY TO A SCORCHED FIELD AND SOME BURNED TREES.

Ntsbnumber: PLD74XR006

Report Number: PAR-75-02

Addressee Name: RSPA

Addressee Status: Closed - Unacceptable Action

Addressee Date Closed: 1988-09-29

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1976-05-10

Communication Type: Official Correspondence

Communication Contents: LTR FROM MTB: OPSO HAS DISCUSSED THIS MATTER WITH AGA AND WITH VARIOUS OPERATORS. WE ARE OF THE OPINION THAT AT THIS TIME IT WOULD BE INAPPROPRIATE TO DEVELOP ADDITIONAL REGULATIONS CONCERNING CROSSOVER LINES AND VALVES. 7/19/76-LTR FROM MATERIALS TRANSPORTATION BUREAU: WE HAVE EXTENDED UNTIL JANUARY 1977 OUR SCHEDULED COMPLETION OF THE EVALUATION OF THE CONTRACT STUDY ON RAPID SHUTDOWN OF FAILED PIPELINE SYSTEMS. WE WILL ADVISE YOU IF WE CHANGE OUR CONCLUSION THAT REGULATORY ACTION CONCERNING CROSSOVER VALVES IS NOT NEEDED.

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1983-03-21

Communication Type: Official Correspondence

Communication Contents: WHEN A MAJOR SYSTEM MALFUNCTION OR ACCIDENT OCCURS IN A GAS TRANSMISSION OR DISTRIBUTION PIPELINE SYSTEM, IT IS IMPORTANT TO RAPIDLY ISOLATE AND REDUCE THE PRESSURE AND FLOW IN THE AFFECTED PIPELINE ARTERIES. OFTEN, HOWEVER, VALUABLE TIME IS LOST AS THE EMERGENCY IS DEVELOPING WHILE MAINTENANCE AND EMERGENCY RESPONSE PERSONNEL ARE LOCATING AND CLOSING THE REQUIRED KEY VALVES, AND PERFORMING OTHER EMERGENCY RESPONSE ACTIVITIES. AUTOMATIC LINE VALVES AND FAILURE ALARM SYSTEMS THUS SERVE IMPORTANT SAFETY FUNCTIONS AS PROTECTION AGAINST EXCESS PRESSURE OR PRESSURE DROPS RESULTING FROM OPERATIONAL FAILURES. THESE DEVICES, INCLUDING, IN GENERAL, EMERGENCY RESPONSE PROCEDURES, ARE ALL RELATED TO THE SAFETY SYSTEM OBJECTIVE OF MINIMIZING OR REDUCING "LOSS OF PIPELINE SYSTEM CONTROL." WITHIN THE CONTEXT OF THE FOLLOWING DIAGRAM, AUTOMATIC LINE VALVES AND FAILURE ALARM SYSTEMS ARE AN INTEGRAL ASPECT OF EMERGENCY RESPONSE PROCEDURES. IT SHOULD BE NOTED, HOWEVER, THAT EMERGENCY RESPONSE PROCEDURES APPEAR AT A VERY HIGH LEVEL OF THIS FAULT TREE AND, THEREFORE, PRESENT THE POTENTIAL FOR SUBSTANTIAL SAFETY IMPROVEMENTS THROUGH DEVELOPMENT OF MORE EFFICIENT EMERGENCY RESPONSE PROCEDURES. IN MARCH OF 1976, THE MTB AMENDED PART 192 (DOCKET OPS-32) WHICH CLARIFIED AND FURTHER DELINEATED THE REQUIREMENTS OF SECTION 192.615 THAT PIPELINE OPERATORS PREPARE AND EXECUTE AN EMERGENCY RESPONSE PLAN AND PROCEDURES. SPECIFICALLY WITH REFERENCE TO AUTOMATIC LINE VALVES AND FAILURE ALARMS, SECTION 192.615(A), EMERGENCY PLANS, STATES THAT: EACH OPERATOR SHALL ESTABLISH WRITTEN PROCEDURES TO MINIMIZE THE HAZARD RESULTING FROM A GAS PIPELINE EMERGENCY. AT A MINIMUM, THE PROCEDURES MUST PROVIDE FOR ... EMERGENCY SHUTDOWN AND PRESSURE REDUCTION IN ANY SECTION OF THE OPERATOR'S PIPELINE SYSTEM NECESSARY TO MINIMIZE HAZARDS TO LIFE, OR PROPERTY. THE USE OF AUTOMATIC LINE VALVES AND FAILURE ALARM SYSTEMS AS POSSIBLY ENVISIONED BY P-75-7 AND -8 ARE THUS TWO STEPS THAT CAN BE TAKEN IN APPLYING THE PERFORMANCE STANDARD OF SECTION 192.615(A). ALTHOUGH FAILURE ALARM DEVICES AND AUTOMATIC VALVES MONITOR IMPORTANT SYSTEM PARAMETERS, SUCH AS DETECTING PRESSURE GRADIENTS IN GAS FLOW, AND PLAY AN IMPORTANT ROLL IN MINIMIZING OR REDUCING LOSS OF SYSTEM CONTROL, THEY APPEAR AT A LOWER LEVEL IN THE FAULT TREE.THE INDICATE THAT THERE ARE VARIOUS ALTERNATIVES AND COMBINA TIONS OF ALTERNATIVES THAT CAN BE TAKEN (AND IN THE CASE OF EMERGENCY RESPONSE PROCEDURES, HAVE BEEN TAKEN) BY THE MTB OR THE INDUSTRY TO ACHIEVE THE SYSTEM SAFETY OBJECTIVE OF MINIMIZING LOSS OF SYSTEM CONTROL. ACCORDINGLY, IT IS REQUESTED THAT RECOMMENDATIONS P-75-7 AND -8 BE CLASSIFIED AS "CLOSED--ACCEPTABLE ALTERNATIVE ACTION."

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1988-09-29

Communication Type: Official Correspondence

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1976-08-10

Communication Type: Official Correspondence