Tempered glass is made from normal annealed glass via a thermal tempering process in which the glass is subjected to heat till its softening point and then rapidly cooled. This gives the glass its strength. A fully tempered glass is used in most modern glass facade, where glass strength is required. A fully tempered glass is recommended for windows that are on high floors or skylights where people are required to stand on top for cleaning. Also areas where risk of thermal breakage or impact breakage is high, fully tempered glass should be used so as to avoid risk of injury. Glass strength is also required in point fixed glazing, bolted and patch fittings.