Formamide is a constituent of cryoprotectant vitrification mixtures used for cryopreservation of tissues and organs. Methods include advanced oxidation processing, distillation, adsorption, ozonation, vitrification, incineration, chemical immobilisation or landfill disposal. Inc. Fahy is the world's foremost expert in organ cryopreservation by vitrification. Cooling and solidification without crystal formation is called vitrification. Cryoprotectant mixtures have been used for vitrification (i.e. solidification without crystal ice formation). Eleven debris pits were also treated with in-situ vitrification. The second technique for cryoconservation is vitrification or flash freezing. Bulk vitrification uses electrodes to melt soil and wastes where they lie buried. Bulk vitrification uses electrodes to melt soil and wastes, which are then buried underground. Pottery can be made impermeable to water by glazing or by vitrification. In 1996, DWPF introduced radioactive material into the vitrification process. The vitrification process creates porcelain tiles that contain a glass substrate. It compared vitrification (the newest technology) versus slow freezing (the oldest one). Different clay bodies reach vitrification at different temperatures. The waste fuel, called high level liquid waste, is converted to glass through vitrification.