Tempered glass is produced by heating annealed glass in a furnace to 620°C. Progressing from the furnace, the glass is rapidly ... thermal breakage than annealed or heat strengthened glass If breakage occurs the glass breaks up into small, cubical fragments, ... windows, doors, shopfronts in offices, houses, shops etc. Interior glass screens, partitions, balustrades etc. Shop display windows, showcases, ...