Abstract: On September 3, 2007, thirty nine employees reported severe respiratory symptoms from exposure to chlorine dioxide gas, resulting in thirty five of those going to the hospital and two being admitted overnight. Pacific Coast Producers Inc. is a food processing company that operates fruit canneries. Flumes carry the tomatoes from the trucks into the sort area, and this flume water was disinfected with chlorine dioxide. The chlorine dioxide was generated on site, and dispensed into the flume water. A demand probe in the south round tank fouled with organic matter, causing the system to continue to pump chlorine dioxide into the flume water. Levels increased as the sensor fouled, causing it to off-gas into the sort area. Twenty two injured employees were on the third shift, nine on the second shift, and eight employees on the first shift. The two hospitalized employees, Employee #1 and Employee #2 were both on the third shift, where concentrations of chlorine dioxide were reportedly the highest. At approximately 4:30 to 5:00 a.m., all employees working on the sort lines who had not already requested first aid were moved to first aid and the sort area was evacuated. The chlorine dioxide generating system was shut down, and Emergency Services was called. The Woodland Fire Department responded with several trucks and ambulances. They triaged thirty nine employees, with thirty five going to various regional hospitals or clinics, and two being held overnight. Employee #1 and Employee #2 were taken to Woodland Memorial Hospital for about thirty six hours for treatment of pulmonary edema and bronchial inflammation. They had not returned to work before the season ended and all the seasonal staff were laid off. The other employees suffered from respiratory tract irritation and returned to work on their next shift.