Video: Safety Issues Led to Fatal Hydrogen Chloride Release

Several safety issues contributed to the fatal hydrogen chloride release in 2020 at the Wacker Polysilicon North American facility in Charleston, Tennessee, according to a video about the incident published by the U.S. Chemical Safety and Hazard Investigation Board on Oct. 17. According to CSB, Wacker’s lack of written maintenance procedures, procedures for controlling hazardous energy, and procedures for simultaneous operations, as well as inadequate means of exiting the affected area, contributed to the incident’s severity.

The incident involved contract workers from two firms who were conducting separate tasks on the fifth floor of an equipment access platform at the facility. Workers employed by one of the contracting firms were tasked with bolt torquing and wore full-body chemical-resistant suits. The workers employed by the other contractor wore flame-resistant clothing as they insulated equipment. When one worker excessively tightened the bolts on a pipe containing hydrogen chloride, the pipe cracked, releasing the chemical onto the platform. Three workers not wearing chemical-resistant suits attempted to escape by climbing down the side of the structure. All three fell to the ground, roughly 70 feet below—one was killed, and two were seriously injured.

CSB’s new video features animation depicting the events that led to the incident, commentary from a CSB board member and investigators, and an outline of the agency’s recommendations for addressing the safety issues that led to the chemical release. For example, CSB stresses the need for OSHA to require facility owners and operators to coordinate simultaneous operations.

The new safety video is available on CSB’s YouTube channel. More information can be found in the agency’s news release about the video and on its investigation page for the November 2020 incident.