Abstract: At approximately 7:30 a.m. on November 2, 2007, a technician in building Number II was conducting weld-penetration tests with a chemical solution containing 95-percent ethyl nitric acid (70-percent concentration). An old container of the solution in a storage can that had been stored on a bottom shelf fell and broke when the lower shelf in the cabinet collapsed. When the technician heard the noise he opened the cabinet to investigate. The fumes spread throughout the work area of building Number II. The building housed 400 employees. A number of employees complained of nausea and difficulty breathing. Twenty three employees that were exposed were transported to the hospital. Six employees were admitted to the hospital. All were released the next day.