The US Chemical Safety Board has published a case study, ‘Key Lessons for Preventing Inadvertent Mixing During Chemical Unloading Operations’, which examines the events surrounding the October 21st 2016, chlorine gas release from the MGPI Processing Plant in Atchison, Kansas.
Around 140 people were sent to hospitals as a result of the poisonous cloud, which also forced residents to remain indoors or temporarily evacuate the city. The US CSB’s report outlines a raft of safety recommendations and measures companies should adopt to protect against similar incidents happening in the future.
US CSB chairperson, Vanessa Allen Sutherland, described the delivery and handling of hazardous chemicals as “high risk operations” which “require strict adherence to safety protocols”.
“An inadvertent mixture can result in a chemical reaction with extremely dangerous consequences,” she said. “ Our findings reaffirm the need for facilities to pay careful attention to the design and operation of chemical transfer equipment to prevent similar events.”
‘Human factors’
The MGPI facility produces distilled spirits and specialty wheat proteins and starches. The chemical release occurred when sulfuric acid was inadvertently unloaded from a tanker truck into a fixed sodium hypochlorite tank at the plant. The two materials combined to produce chlorine gas and other by-products.
- The CSB’s final report includes 11 key lessons and outlines clear safety improvements that can be implemented at similar facilities across the country. Among these facilities should evaluate chemical unloading equipment and processes, and implement safeguards to reduce the likelihood of an incident, while taking into account human factor issues that could impact how facility operators and drivers interact with equipment.
- Facility management should evaluate their chemical transfer equipment and processes and, where feasible, install alarms and interlocks in the process control system that can shut down the transfer of chemicals in an emergency.
View the full US CSB case study
Watch: ‘Mixed Connection, Toxic Result’
As part of its report, the US CSB released animated simulation video, “Mixed Connection, Toxic Result,” highlighting the safety lessons.
More about the US CSB
The CSB is an independent federal agency charged with investigating serious chemical incidents. The agency’s board members are appointed by the president and confirmed by the Senate. CSB investigations look into all aspects of chemical incidents, including physical causes such as equipment failure as well as inadequacies in regulations, industry standards, and safety management systems.
