Chemical manufacturer AB Specialty Silicones LLC has agreed to pay $1.3 million in penalties in connection with a May 2019 explosion and fire at its Waukegan, Illinois, plant that claimed the lives of four workers, the Occupational Safety and Health Administration (OSHA) announced October 2.

Following OSHA’s investigation, it proposed penalties totaling $1,591,176 for four alleged willful violations. OSHA cited AB Specialty Silicones with willful violations of federal electrical equipment, flammable liquid, and powered industrial trucks standards.

As part of the agreement between OSHA and AB Specialty Silicones, the company has temporarily ceased the production and use of silicon-hydride emulsions at all its facilities until a new process area for production is designed by an engineering firm.

The employer also agreed to do the following: 

• Develop a companywide safety and health management system, implement an emergency action plan, and conduct evacuation drills. 
• Provide safety training to employees, offering it in languages employees understand. 
• Require specialty training for management on the handling of flammable materials.
• Purchase industrial trucks for all its facilities that are properly rated for handling flammable materials. 
• Perform comprehensive audits of the company’s occupational health and safety management system certification, and maintain certification at all its facilities. 
• Hire third-party consultants to assist with analyzing electrical classification and hazards for any future or rebuilt facilities, and audit facilities 6 months after the start of operations.
• Allow OSHA to periodically inspect facilities without requiring a warrant.

AB Specialty Silicones agreed to pay the penalty in 12 quarterly installments through September 1, 2027. If the company misses a quarterly payment, the penalty becomes due immediately.

“This agreement will never replace the four workers lost in this preventable tragedy, but it’s a step in the right direction,” Bill Donovan, OSHA’s Chicago regional administrator, said in an agency statement. “OSHA will continue to hold AB Specialty Silicones accountable for improving their safety culture by working with industry experts, and both management and employees to develop and continually test safety measures, emergency response procedures and training employees in hazard recognition.”

The U.S. Chemical Safety and Hazard Investigation Board (CSB) also investigated the explosion and fire at the company, releasing its final report in September 2021. The CSB investigates major chemical accidents but doesn’t cite employers or issue penalties.

According to the CSB’s report:

• On May 2, 2019, operators at the facility were performing a batch operation that involved manually adding and mixing chemicals in a tank inside the production building when an operator pumped the incorrect chemical into a tank, which was incompatible with another chemical added to the tank.
• After the chemicals were mixed, the tank contents underwent a chemical reaction, causing them to foam, overflow from the tank’s top opening, and form a fog.
• The reaction produced hydrogen gas, which was released inside the manufacturing facility’s production building. The hydrogen gas ignited, causing a massive explosion and fire and fatally injuring four employees.
• The explosion and fire destroyed the facility’s production building.

In its final report on the incident, the CSB reiterated its earlier recommendations, urging the Environmental Protection Agency (EPA) to revise its risk management plan (RMP) regulations and OSHA to revise its standard for the process safety management (PSM) of highly hazardous chemicals.

In May 2022, the CSB released a video describing its investigation of the events leading up to the explosion and fire at the facility.