A protective layer is applied to a work piece to protect the surface during charged particle beam processing by directing a fluid toward the surface. The surface is preferably not touched by the applicator. Ink jet print-type print heads are suitable applicators. Ink jet-type print heads allow a wide variety of fluids to be used to form the protective layer. Useful fluids that form protective layers include colloidal silica having small silver particles and hydrocarbon-based inks.