Tempered glass is well-built and more substantial than other normal or cooling process annealed glasses. The superior retrenchments of the inner layer during manufacturing constrict stresses in the surface of the glass evenhanded by tensile stress in the body of the glass. For tempered glass to be considered safety glass, the compact facade tension should exceed 15,000 psi. Due to the result of this increased facade tight tension, when tempered glass breaks, the glass smashes into small grainy amounts instead of breakage into pointy debris as most normal glass does.
Compressive surface stresses give tempered glass increased strength. Cooled processed annealed glass has almost no internal pressure and usually forms microscopic cracks on its surface. Tension applied to the glass can drive crack propagation which, once begun, concentrates stress at the tip of the damage, moving crack propagation at the speed of sound through the glass. Consequently, annealed glass is fragile and breaks into irregular and sharp pieces. The compressive stresses on the surface of tempered glass contain flaws, preventing their propagation or expansion.
Any cut, grind, and quick contacts after tempering will cause the glass to breakage. Any amount of cut and grind will have to be done before the process of tempering. The surface tension mold resulting from tempering can be experimented with by viewing from optical polarizer sunglasses. The Architectural Glass stress becomes relatively even due to the resulting surface tension mold, and glass strength becomes four to five times higher than standard glass. Breaking a piece of glass by hitting the edges and corners is the easiest way to break tempered glass. When the tempered glass shatters, it smashes into small grainy amounts, which won't cause severe injuries to humans.
Tempered glass also comes with limited color options; it only comes in green, blue, grey, bronze, clear iron. The tempered glass cannot attain other colors according to what any glass designer or glass architecture wants. But an essential feature and unique property that tempered glass has is its safety because it is beneficial to human lives. Though it may not be applicable for many uses, it does cater to human needs for its security.
