Architectural glass light in industrial factories. Annealed glass is glass without internal stresses caused by heat treatment, i.e., rapid cooling, or by toughening or heat strengthening. Glass becomes annealed if it is heated above a transition point then allowed to cool slowly, without being quenched. Float glass is annealed during the process of manufacture. However, most toughened glass is made from float glass that has been specially heat-treated. Annealed glass breaks into large, jagged shards that can cause serious injury and is considered a hazard in architectural applications. Building codes in many parts of the world restrict the use of annealed glass
Studio glass of techniques in creating their pieces. The ancient technique of blown glass, where a glassblower works at a furnace full of molten glass using metal rods and hand tools to blow and shape almost any form of glass, is one of the more popular ways to work. Most large hollow pieces are made this way, and it allows the artist to be improvisational as they create their work. Another type is flame-worked glass, which uses torches and kilns in its production. The artist generally works at a bench using rods and tubes of glass, shaping with hand tools to create