Abstract: On October 3, 2001 Employee #1, a plant manager, explained that the three part automated cleaning system of a cream yeast system failed to keep the chemicals separated. It appears that a valve failed during the three part cleaning system, allowing caustic acid and sanitizer to mix. The result of the mixture created a chlorine gas exposure to a total of 31 employees who were sent to the hospital. Employees #1, #2, and #3 remained overnight for further evaluation. The employees had not been provided training on the chemicals they were utilizing in the cleaning system nor were they trained on the evacuation procedure in the event of a release. The company was utilizing new chemicals, which contained sodium hypochlorite, for approximately one month. The caustic containing sodium hypochlorite was not recommended by the manufacturer of the cleaning system. The employees were not trained on emergency response procedures for a chemical release.