NTSB Safety Recommendation P-71-001

NTSB safety recommendation P-71-001.

THE NTSB RECOMMENDS THAT THE OFFICE OF PIPELINE SAFETY OF THE DEPARTMENT OF TRANSPORTATION: CONDUCT A STUDY TO DEVELOP STANDARDS FOR THE RAPID SHUTDOWN OF FAILED NATURAL GAS PIPELINES AND WORK IN CONJUNCTION WITH THE FEDERAL RAILROAD ADMINISTRATION TO DEVELOP SIMILAR STANDARDS FOR LIQUID PIPELINES.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 1970-12-30

Adopted Date: 1970-12-30

Overall Date Closed: 1976-09-30

Synopsis: "SPECIAL STUDY OF EFFECTS OF DELAY IN SHUTTING DOWN FAILED PIPELINE SYSTEMS AND METHODS OF PROVIDING RAPID SHUTDOWN." IN ALMOST ALL RECENT PIPELINE ACCIDENTS, THE DELAY IN SHUTTING DOWN THE FAILED PIPELINE SYSTEM HAS RESULTED IN AN INCREASED MAGNITUDE OF CATASTROPHE. WITH THE EVER INCREASING USE OF PIPELINES FOR NATURAL GAS AND OTHER HAZARDOUS MATERIALS AND THE PROXIMITY OF THESE LINES TO EXPANDING POPULATED AREAS, IT IS IMPERATIVE THAT SYSTEMS AND METHODS BE DEVELOPED AND PUT TO USE WHICH WILL PROVIDE FOR THE RAPID SHUTTING DOWN OF FAILED PIPELINE SYSTEMS.

Ntsbnumber: 80420

Report Number: PSS-71-01

Addressee Name: RSPA

Addressee Status: Closed - Acceptable Action

Addressee Date Closed: 1976-09-30

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1976-09-30

Communication Type: Official Correspondence

Communication Contents: This is to inform you that the National Transportation Safety Board, by formal Board action, has closed out the following Safety Recommendation: Address: OPS (Office of Pipeline Safety) Recommendation: P-70-1, Date issued: February 12, 1971, and Criteria: CLOSED—ACCEPTABLE ACTION.

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1971-04-12

Communication Type: Official Correspondence

Communication Contents: - From Willard J. Smith, Assistant Secretary for Safety and Consumer Affairs, Office of the Secretary of Transportation: Secretary Volpe has asked me to reply to your letter of February 2, 1971, and comment on the study enclosed therewith entitled, "The Effects of Delay in Shutting Down Failed Pipeline Systems and Methods of Providing Rapid Shutdown." The study recommends that the Office of Pipeline Safety conduct a study to develop standards in that area. The Department's concern is with both liquid and gas pipelines. With respect to liquid lines, the Federal Railroad Administration has, since December 31, 1967, required the filing of accident reports by liquid carriers whenever there is a liquid or vapor release of the commodity transported resulting in one or more of the items set forth in Section 195.50 of the liquid pipeline safety regulations. So far as we can determine, based on review of three years of liquid line accidents, the severity of the accidents could not have been substantially reduced by the installation of automatic valves along the line or by the reduction in valve spacing. We are, however, evaluating the needs for requiring the installation of automatic shutdown equipment on existing pump stations similar to that being installed on new stations. The reporting of individual leaks for gas lines began on February 9, 1970. Thus, the reporting experience is only a little over a year old and an analysis of leak reports has not been completed. It is our opinion that, before undertaking a study on the rapid shutdown of failed facilities, an analysis of the reports should be made to ascertain whether or not accidents could be reduced by more rapid shutdown. If the review of the leak reports indicates the values of such a study, the Board’s recommendation will certainly be followed. The possibility of including requirements for rapid shutdown of systems by automatic means was given considerable discussion and review during the course of preparing the Federal gas pipeline standards, which were issued on August 11, 1970. Included in this review was the possible increase in present valve spacing requirements for valves in transmission lines. The decision was made not to propose any change in requirements at that time. The reason for this decision were: 1. The main thrust of the new regulations was toward the prevention of accidents. Thus, the main objective was to have the regulations designed to prevent failures from occurring, rather than to minimize the release of gas after a failure had occurred. 2. It is questionable whether the technology of automatic shutdown devices has advanced to a point where it is feasible to require their installation by regulation. This is true in both gas and liquid pipeline systems. While certain limited applications have proven successful, discussion with operators and equipment manufactures reveal that a greater hazard could possible exist through the increase use of such devices, because their malfunction could close off the flow during normal operations. 3. Valves are mechanical devices with moving parts. They, as well as other such devices, are a source of leakage. Installation of more valves would provide another source of leakage both in gas and liquid pipeline systems. 4. At the time of developing the regulations, there was insufficient evidence to indicate that the severity of accidents would be reduced by reducing the valve spacing or by the installation of automatic shutdown devices. This is true in both gas and liquid systems. It must be remembered that once a leaking section a pipeline is isolated, the commodity in that section will still be released and most damage is caused by the initial volumes released. We will report to the Board again on this matter ager completing the study of leak reports mentioned above.

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1971-07-16

Communication Type: Official Correspondence