Abstract: At approximately 11:30 a.m. on October 9, 2006, an employee was working for a research and manufacturing facility in Fremont, California, that produced phosphors for white LEDs and other lighting applications. The employee, a "Wet Lab" technician, was using a hand pump to transfer liquid ammonium hydroxide from a glass carboy on a rolling cart, to containers of chemical mixtures inside a standard laboratory hood. A small, 0.25 in. plastic hose at the base of the pump, separated from the pump, which then sprayed approximately 10-30 ml. of liquid onto the employee's face, neck, and throat. The hand pump had no clamp or other fastening device to hold the worn hose onto the pump base. The employee was taken by ambulance to Washington Hospital in Fremont, and was hospitalized overnight for observation. The employee was treated for chemical burns to the face, neck, mouth, and nose, and for inhalation of chemical vapors.