There are two distinct categories of heat-treated glass products, heat-strengthened and fully tempered, differentiated by the degree of residual compression and/or the edge compression that exists in the material after heat treatment. We are happy to help you determine which option is the most appropriate for your project.

Fully Tempered Glass

Fully tempered glass is glass that has been heat-treated to have a minimum surface compression of 10,000 psi (69MPa), making it approximately four times stronger than annealed glass of the same thickness and configuration. Tempered glass is considered a safety glazing material because it dices, or crumbles, when broken, leaving no large shards and reducing the risk of serious injury. These characteristics make fully tempered glass ideal for applications where strength is paramount or in cases where a human might reasonably impact glass.

Heat-Strengthened Glass

Heat-strengthened glass is glass that has been heat-treated to have a surface compression between 3,500 and 7,500 psi (24 to 52 MPa), making it approximately twice as strong as annealed glass of the same thickness and configuration. Unlike fully tempered glass, heat-strengthened glass is not considered a safety glazing material. Accordingly, heat-strengthened glass is the preferred product for projects that do not require safety glass but are likely to be met with thermal or mechanical loads.