Abstract: At approximately 4:10 p.m. on August 25, 2017, Employee #1, who had been performing maintenance work on the machines, wearing a flame resistant uniform, came into the supervisor's office. The employee reported that he was feeling very bad. Employee #1 said that he had vomited twice during the day after drinking water and Gatorade, but was not urinating. The employee started to sweat profusely. He suddenly stopped sweating, had involuntary muscle spasms, and was having difficulty speaking. The supervisor helped him remove the uniform that he was wearing and applied cool wet rags to his upper body and head. Emergency medical services were contacted and the employee was transported to a local hospital. Employee #1 was treated for hyponatremia, dehydration and possible heat stroke.