CSB Chair: Fatal DuPont Incident Mirrors Industry's Shortcomings
"Complex process-related accidents with tragic results are taking place across the country at companies of all sizes. This problem includes major corporations such as DuPont, not just smaller companies that some refer to as outliers. It is clear that the current process safety regulatory system is in need of reform, and that companies themselves must do more," Chairperson Rafael Moure-Eraso said during a media briefing about the investigation of the November 2014 incident.
Rafael Moure-Eraso, who chairs the federal Chemical Safety and Hazard Investigation Board, and board member Manual Ehrlich briefed Houston media Feb. 5 on CSB's ongoing investigation of the methyl mercaptan release at DuPont's La Porte facility on Nov. 15, 2014, that killed four workers. Both CSB board members had visited the accident site the prior day. Moure-Eraso thanked DuPont for cooperating with the investigative team and also thanked International Chemical Workers Union local 900C. He noted this was the third fatal incident at DuPont that the board has investigated during his five years as its chair.
"This is my fifth and final year serving as chairperson of the U.S. Chemical Safety Board. During that time the CSB has investigated three major, fatal accidents at DuPont facilities around the U.S. The frequency of these incidents is a concern for the board as well as for DuPont, its workers, family members, and the communities nearby," he said, according to the statement posted on CSB's website. "The first DuPont accident investigated by the CSB, in January 2010, at DuPont's manufacturing plant in Belle, West Virginia, resulted in the death of one worker when a braided steel hose ruptured, releasing highly toxic phosgene gas. The CSB investigation found that DuPont had not used the safest materials of construction for the hose – had not replaced the hose on the required maintenance schedule – had not installed a properly ventilated and alarmed enclosure around the phosgene to prevent worker exposure – and finally, had not required workers to use respirators around the phosgene storage area.
"The second DuPont accident investigated by the CSB occurred later in 2010 when hot sparks produced by welding ignited flammable vapors inside a chemical storage tank that had not been effectively isolated from a hazardous process at DuPont’s facility in Buffalo, New York. The tank had not been effectively isolated from a hazardous process. DuPont had not used an adequate gas detection system to monitor the area for the hazardous vinyl fluoride gas, which exploded. And finally, the accident we are discussing today – at the DuPont, La Porte facility here in Texas – was the most severe. Four workers were killed during the release of what DuPont estimates were more than 23,000 pounds of methyl mercaptan, a highly toxic, flammable, and volatile liquid.
"Now let me say that DuPont has long been regarded as one of the industry's safety leaders," Moure-Eraso continued. "In fact, DuPont has been viewed as an industry leader in processing hazardous materials for most of the last two centuries. After the Bhopal tragedy in 1984, the DuPont La Porte facility changed its production of methyl isocyanate – or MIC – the same chemical involved in the Bhopal accident, to an inherently safer method so that the highly hazardous chemical was no longer stored in large quantities but was used as it was produced. Such action has contributed to DuPont's reputation as a leading light in safety; its slogan is: 'Zero' safety incidents. The company markets its safety programs to other in the chemical industry. But we have found that not only DuPont, but the industry as a whole, must do much better. Complex process-related accidents with tragic results are taking place across the country at companies of all sizes. This problem includes major corporations such as DuPont, not just smaller companies that some refer to as outliers. It is clear that the current process safety regulatory system is in need of reform, and that companies themselves must do more."
He then listed common factors CSB has identified as contributing to major accidents like the one at DuPont La Porte: "These include a lack of safe process designs and risk reduction targets, weak or obsolete regulatory standards, inadequate regulatory resources and staffing, and overly permissive industry standards. And the latest accident at DuPont is one of many incidents investigated by the CSB where we believe it will become clear that the process design was not as safe as possible."
The process at La Porte included several interconnections between the methyl mercaptan supply line and a chemical vent system, which allowed a toxic leak into an unexpected location, where the workers were exposed, he explained. The chemical vent system, intended to safely remove harmful vapor from process vessels, had a design shortcoming that allowed liquid to accumulate inside, requiring operators to manually drain them, and the vent drain they had to use was open to the atmosphere, so workers were exposed to whatever chemicals were drained from the vent system. He also said the building was designed in such a way that, even if ventilation fans had been working on the day of the accident, "it would likely not have effectively protected workers from chemical exposure. And we found that those ventilation fans were not, in fact, working at the time of the accident."