Tempered glass is a type of safety glass processed by controlled thermal or chemical treatments to increase its strength compared with normal glass. Tempering puts the outer surfaces into compression and the interior into tension. Such stresses cause the glass, when broken, to crumble into small granular chunks instead of splintering into jagged shards as plate glass (a.k.a. annealed glass) does.

Tempered glass is also as much as 6 times stronger than untreated glass as well as being resistant to impacts. The safety glass credentials come in when tempered glass is broken into smaller, rounder edged pieces. Whereas normal annealed glass shatters into sharper edged pieces that are much more likely cut the skin on contact. The safety and strength of tempered glass make it desirable for a variety of architectural and decorative applications in the home and commercial environments.

How's tempered glass made?
Although annealed glass can be transformed into tempered glass via chemical reaction and ion exchange when the glass is immersed in a potassium salt bath at 300°C, chemically tempered glass is inferior to heat toughened glass because it still breaks into sharp splinters and can’t regarded as safety glass without lamination.

Where's tempered glass used?
Because it’s both super-strong and super-safe, tempered glass is used in a variety of traditional decorative and architectural applications. These might be in the home or commercial settings including the automotive, technological and sports/leisure industries. Applications may include anything from shower doors and fridge trays to mobile screen protectors and diving masks.