glossary Glossary 2 min read

toughened glass

Toughened (tempered) glass is heat-treated to break into small blunt fragments. Required as Grade A safety glazing in doors, bathrooms and low windows under AS 1288.

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Toughened glass (also called tempered glass) is annealed glass that has been heated to around 620 degrees Celsius and rapidly cooled, creating surface compression stresses that increase its strength by up to four times compared to standard annealed glass. When toughened glass fractures, it shatters into small, relatively blunt cubic fragments rather than large, knife-edged shards, significantly reducing the risk of serious laceration injury. It is classified as Grade A safety glass under AS/NZS 2208:1996 and satisfies the AS 1288:2021 safety glazing requirement in doors, bathrooms, low-level windows, shower screens, and other human impact zones. Monolithic toughened glass cannot be cut or drilled after tempering; sizing must be done before the heat treatment process.

Also known as: tempered glass

Category: Glass types

See also

  • Safety glazing, the broader category that includes toughened glass (Grade A)
  • Laminated glass, the alternative Grade A type mandated in high balustrades and overhead glazing

Last updated: 2026-05-08. Verified: 2026-05-08. Quarterly review for currency.