Laminated glass is commonly used in situations where there is a chance of impact or breakage. A layer of polyvinyl butryal is sandwiched between two sheets of glass, keeping them bonded even when broken and preventing the glass from breaking up into large sharp pieces.
Characteristic spider-web-like crack patterns can be seen on laminated glass panels when the impact has been insufficient to completely pierce the material.
This type of glass also provides improved sound insulation, and hence is used in installations such as meeting room walls or office doors such a quality is desirable. It is also often used to reduce traffic noise in hotels or residential developments.