Abstract: Employee #1 was alone while cleaning parts from vapor deposition system #6, which applies a thin amorphous silicon layer onto glass in a heated chamber. He was told to clean the metal parts of the apparatus, which holds the glass plate during the coating process, with isopropyl alcohol in a vent sink. After unsuccessfully attempting to clean the parts with alcohol, he decided to use a solution of HF-HNO3 -- the solution applied from a squeeze bottle is used for cleaning a similar system. To clean the screws, he mixed approximately 500 ml of undiluted HF and HNO3, 1:1 in a 1,000 ml beaker. He noticed a mild reaction as the screws were dropped into the beaker. To clean the brackets, he mixed approximately 2,000 ml of undiluted HF and HNO3, 1:1 in a 3,000 ml beaker. There was an immediate and violent reaction which caused the solution to discharge from the beaker. The introduction of the metal into the solution caused the violent reaction by a release of gas and/or rapid boiling. Approximately 300 ml of the solution struck Employee #1's face. He was wearing a face shield, acid gloves, and an apron; however, the face shield was slightly raised. He sustained 2nd-degree chemical burns to the right side of his face and right ear and damage to the first epidermis of the right eye. Employee #1 had been employed at Xerox approximately 3 months through Perma Temp, a temporary agency. Xerox had trained him to disassemble and clean the system, position the larger parts in the vent sink, and apply the HF-HNO3 solution out of a squeeze bottle. He was also informed of the hazard created by mixing acids with bases. He was not, however, ever informed of the incompatibility of mixing acids and metals, and a general citation was issued.