Tempered Glass is a type of safety glass processed by controlled thermal to increase its strength by bringing its interior into tension while the outer surfaces are put into compression.The glass is placed onto a roller table, taking it through a furnace that heats it well above its transition temperature. The glass is then rapidly cooled with forced air drafts while the inner portion remains free to flow for a short time.

Such stresses cause the glass, when broken, to crumbles into small granular chunks instead of splintering into jagged shards to minimize the possibility of harm.

Tempered glass must be cut to size or pressed to shape before tempering, and cannot be re-worked once tempered. Polishing the edges or drilling holes in the glass is carried out before the tempering process starts.