The employee worked most of the day clearing choked equipment sometimes close to the heater. He drank water. Reported feeling tired. Finished at 8:00 pm. At home felt very tired, nauseous, vomiting. Went to the ER. Treated for heat exhaustion, heat cramping, strep throat. Released 2:03 am. Called out sick 8/11/07. Returned to work 8/12/07. Reported incident to management 9/12/07.