Catastrophic Vessel Overpressurization, Pitkin, Louisiana - March 4, 1998

Board Report on Louisiana Oil and Gas Production Facility Accident That Killed 4 Workers Says Lack of Facility Design Review, Hazard Analysis Among Causes

(WASHINGTON, D.C. - September 29, 2000) The U.S. Chemical Safety and Hazard Investigation Board's (CSB) newly-adopted report on a fatal 1998 Louisiana catastrophic vessel failure says the incident would likely have been prevented with an effective engineering design review process or hazard analysis, and vessel overpressure protection.

The investigation report, the Board's fifth to be released since it began operations in 1998 and the second released this year, examined the March 4, 1998 catastrophic vessel failure and fire at Sonat Exploration Company's (now El Paso Production Company) Temple 22-1 Common Point Separation Facility near Pitkin, Louisana.

The Board, in addition to its findings of fact and root and contributing causes, issued recommendations aimed at preventing recurrence of such an incident. The recommendations were addressed to the company and the American Petroleum Institute (API).

At the time of the incident, the facility housed separation equipment used to produce oil and natural gas from nearby wells. Workers were purging a two-mile pipeline between an oil and gas well and the facility's separation equipment when a vessel ruptured due to overpressurization, releasing flammable material, which then ignited. Natural gas from the ruptured vessel produced a large fireball, which damaged nearby piping and released and ignited additional flammable materials. Four workers who were in the vicinity of the vessel when it failed died instantly due to massive trauma.

In the incident, a third-stage separator, not equipped with a pressure-relief device, was significantly overpressurized, resulting in catastrophic vessel failure.

The report says a formal engineering design review process should have been in place during the design of the facility. Effective design review and hazard analysis would have provided an opportunity to analyze the consequences of foreseeable deviations from normal operating procedures, such as valve misalignments. This process would likely have identified the danger of catastrophic overpressurization of the third-stage separator and indicated the need for a pressure-relief system.

The Board also found that Sonat did not meet relevant industry consensus guidelines for pressure relief. The vessel that failed met the definition of a two-phase gas-oil separator and should have been designed to the ANSI/API Specification 12J-1992, "Specification for Oil and Gas Separators," which stipulates that separators be equipped with pressure-relief devices.

RECOMMENDATIONS The Board recommended that El Paso Production Company (formerly Sonat Exploration company) institute a formal engineering design review process for all oil and gas production facilities, following good engineering practices and including analyses of process hazards.

Secondly, the Board recommended that El Paso Production Company implement a program to ensure that all oil and gas production equipment that is potentially subject to over-pressurization is equipped with adequate pressure-relief systems, and audit compliance with the program.

The Board's third recommendation to the company was to develop written operating procedures for oil and gas production facilities and implement programs to ensure that all workers, including contract employees, are trained in the use of the procedures.

Board member Dr. Jerry Poje, who was on-scene in Louisiana shortly after the incident, said the adoption of the Board's recommendations will help prevent similar incidents in the future.

"If the recipients of our recommendations accept and act on them in a timely manner, it will create something positive out of this terrible tragedy that cost four workers' lives and will lessen the chances of a similar incident in the future," Poje said.

The Board immediately made the full text of the report available for viewing and downloading on the CSB web site at http://www.chemsafety.gov. The Board also adopted a recommendation that the API develop and issue recommended practice guidelines governing the safe start-up and operation of oil and gas production facilities. The Board recommended that the guidelines incorporate, at a minimum, the following: project design review processes, including hazard analyses; written operating procedures; employee and contractor training; and pressure-relief requirements for all equipment exposed to pressure hazards.