Abstract: At approximately 2:01 p.m. on June 5, 2006, in the Carbon Processing Room, Employee #1 was monitoring reaction temperature, while adding potassium hydroxide to a reaction vessel that contained other components of a RF Aerogel Synthesis mixture. Employee #2 was observing the process and stood approximately 5 ft away from the reaction vessel. When Employee #1 added an additional 50 grams of potassium hydroxide to the reaction vessel from an aperture at the top of the vessel, an explosion occurred. The experimental procedure was not performed in a laboratory hood, and Employees #1 and #2 were exposed to a mixture of potassium hydroxide, formaldehyde, resourcinol and carbonate on the face, neck and arms. Employee #1 sustained first degree and second degree burns, and Employee #2 sustained minimal first degree burns. Employees #1 and #2 were transported to Valley Care Medical Center in Dublin, CA.