Glasses can be tempered from 4mm to 19 mm thickness. Tempered is done in furnace at a temperature of 680 deg. It makes 1-4 times stronger & strengthens.
After tempering glass become more durable and safe. When broken, it shatters into many small fragments which prevent major injuries. This type of glass is intended for facades, sliding doors, building entrances, bath and shower enclosures and other uses requiring superior strength and safety properties.