May 4, 2023

Lack of Hurricane Preparedness Led to 2020 Chemical Release and Fire, CSB Finds

On April 24, the U.S. Chemical Safety and Hazard Investigation Board (CSB) published a report (PDF) detailing its investigation of an August 2020 chemical fire and toxic gas release that occurred in Westlake, Louisiana, following Hurricane Laura. One of the investigation’s primary findings was that the facility neglected to prepare for severe weather. CSB also identified the facility’s inadequate implementation of process hazard analysis (PHA) recommendations, delayed emergency response, and lack of compliance with applicable hazardous material codes, as well as gaps in OSHA regulations, as factors that contributed to the incident and increased its severity.

According to the report, high winds from Hurricane Laura damaged buildings storing trichloroisocyanuric acid (TCCA) at the Bio-Lab Inc. Lake Charles facility in Westlake on August 27, 2020. At the time, the National Hurricane Center had assigned Hurricane Laura a Category 4 rating, which indicates sustained winds between 130 and 156 miles per hour capable of causing “catastrophic damage.” CSB’s report states that TCCA is a chlorinating agent often used to kill algae and bacteria in swimming pools and hot tubs. In these larger bodies of water, TCCA is soluble and breaks down slowly. However, “[w]hen TCCA instead comes in contact with or is wetted/moistened by a small amount of water and does not dissolve,” the report explained, “it can experience a chemical reaction, generating heat and causing the decomposition of the chemical, which in turn produces toxic chlorine gas and can produce explosive nitrogen trichloride.”

After rainwater from Hurricane Laura contacted TCCA stored in the damaged buildings, heat produced by the chemical reaction caused a fire. The decomposition released a large plume of chlorine and other hazardous gases into the air. Although there were no reported injuries from the incident, the chemical fire and explosion damaged structures at Bio-Lab’s facility. Local officials issued a shelter-in-place order due to the hazardous gas release, and a nearby stretch of Interstate 10 was closed for more than 28 hours afterward.

CSB Chairperson Steve Owens noted that this incident was one of several related to extreme weather that CSB had investigated. “With powerful storms and other extreme weather occurring more frequently,” he said, “companies and regulators must take action to prevent weather-related releases of hazardous chemicals that can cause substantial damage to facilities and threaten surrounding communities.” Bio-Lab had not implemented industry guidance developed after a previous hurricane-related chemical release to prepare the Lake Charles facility for extreme weather.

Bio-Lab had voluntarily implemented some elements of OSHA’s process safety management (PSM) standard, which does not cover TCCA, and even conducted a PHA. However, the company had not followed the PHA recommendation to determine whether the facility’s buildings could withstand hurricane-strength winds. The five-and-a-half-hour delay in Bio-Lab’s emergency response also likely increased the incident’s severity. CSB also found that the facility didn’t comply with National Fire Protection Association codes requiring automatic extinguishing systems and other protections. Finally, CSB noted that if TCCA had been covered under OSHA’s PSM standard or EPA’s risk management program rule, Bio-Lab would have been required to fully implement process safety management elements for its operations relating to TCCA.

For more information, read CSB’s news release.