Abstract: At or about 5:30 p.m. on March 3, 1992, Employees #1 through #6 were performing their regularly assigned duties in the Dip Room when they began experiencing symptoms resembling carbon monoxide exposure, including faintness, nausea, chest pain, and ringing in the ears. All six employees were sent to the hospital and had carboxyhemoglobin levels ranging from 14 to 23 percent. Employees #1, #2, #5, and #6 were admitted. Employees #3 and #4 were treated and released. All six employees returned to work the next day. The Dip Room is a 35 ft by 65 ft enclosure with three doors (kept closed during production) and provided with recirculated air ventilation. That day, a steel platform was being erected on the north wall to store bulk containers of products. Employees #1 through #6 worked along the south wall. Two fork trucks were used to hold the platform until it was permanently secured by maintenance personnel. The project took about 1 1/2 hours. Both fork trucks were left running the entire time. All three doors remained closed until after the employees were sent to the hospital. No management official supervised the project. Management was not contacted until after the employees were experiencing symptoms. Screening tests of the exhaust gases from the propane-powered fork trucks showed carbon monoxide concentrations in excess of 8 percent.