Abstract: At approximately 9:45 a.m. on April 1, 1992, at All Chemical Disposal Inc., Employee #1 and a coworker were putting various chemicals into a dumpster that already contained hazardous waste. A characterization of the hazardous materials being bulked had not been performed and their compatibility with the chemicals was not known. A chemical reaction between the chemicals and the hazardous waste led to a fire. Employees were wearing protective equipment, including respirators. Employee #1 left the area and went into an office to call for emergency assistance. He suffered exposure to chemical vapors and smoke when he removed his respirator to place the telephone call. He also experienced tightness in the chest and blurred vision.