Abstract: Employees #1 and #3 were weavers; Employee #2 was an inspector/assistant supervisor; and Employee #4 was a startup technician. At approximately 7:00 a.m. on January 26, 1995, Employees #1 through #4 began to suffer from headaches, nausea, and dizziness after smelling odors. Employee #1 vomited and Employee #2 lost consciousness. A diesel-fueled Bonnie Scot boiler may have been the source of the odor. The one story building, which had a ceiling of varying heights (approximately 12 to 22 ft) was heated by the boiler. Employees #1 through #4, who were involved in the accident, did not work with the boiler. The maintenance person who came to service the boiler said that the boiler could "puff" when air currents outside the exhaust stack caused pressure changes in the boiler. He also stated that there was soot on the outside of the boiler's rear gasket on that day. The gasket was replaced.