A new safety video from the U.S. Chemical Safety Board (CSB) titled “Blocked In” details the agency’s investigation into the 2013 explosion and fire at the Geismar, La., Williams Olefins Plant that killed two workers and injured more than 160 others. The 12-minute video, which is available on CSB’s website, includes a 3D animation that illustrates the explosion and fire as well as interviews with a CSB investigator and the agency’s chairperson, Vanessa Allen Sutherland.
CSB investigators identified deficiencies in process safety management that led to the incident at the plant, which produced ethylene and propylene for the petrochemical industry. The agency found that these deficiencies allowed a reboiler, a type of heat exchanger, to be unprotected from overpressure and rupture, causing the explosion at the facility. The fire and explosion occurred during an expansion project intended to increase the facility’s production of ethylene. These non-routine operational activities introduced heat to the reboiler, which was offline and isolated from its pressure-relief device at the time of the incident.
“When evaluating overpressure protection requirements for heat exchangers, engineers must think about how to manage potential scenarios, including unintentional hazards,” CSB investigator Lauren Grim says in the video. “In this case, simply having a pressure relief valve available could have prevented the explosion.”
According to CSB, Williams failed to appropriately manage or review changes that introduced new hazards involving the reboiler that ruptured; effectively complete a hazard analysis recommendation intended to protect the reboiler; and perform a hazard analysis and develop a procedure for the non-routine activities being conducted on the day of the incident.
The new video also discusses the recommendations CSB made to the Williams Geismar plant to help prevent future incidents and improve process safety at the facility. The agency recommended that the plant conduct safety culture assessments, develop a robust tracking program for safety indicators, and conduct detailed assessments of its process safety program.