Architectual Glass

Heat Treated


Heat treating is a process that imparts additional strength to flat glass products. Heating and cooling cycles are carefully controlled to produce Heat Strengthened or Fully Tempered glass. Heat strengthened glass is twice as strong as annealed glass but retains the same breakage characteristics. Defined by ASTM C 1048 to have a surface compression between 7500 amd 3500, Heat Strengthened glass is not considered a safety glazing material. Heat Strengthened glass is the preferred process to resist thermal stress and provide additional load resistance when needed.

Fully tempered glass is four times stronger than annealed glass and is considered a safety glazing material. The strength imparted in the tempering process dramatically increases the ability of fully tempered glass to resist bending forces. The heat treating process does not change the rigidity or deflection characteristics of glass. The very high strain induced in the quenching process will cause the glass to fragment into innumerable small fragments or roughly cubicle pieces. The small fragments are rough, sharp, and may interlock. With little structural integrity the majority of the glass often falls from the opening. The interlocking clumps, though properly fragmented, can and do remain intact until impact with a solid surface. This inherent characteristic and the risk of spontaneous breakage are tradeoffs to the added strength and safety for human impact. The design professional should consider the location and proximity of populated areas below fully tempered glazing. The resulting debris from fallout can cause serious injury. Areas of high risk can usually be accommodated with laminated construction to meet code.

Trulite safety glazing products are permanently marked with a logo. This is a trade mark of our organization and it represents our commitment to quality assurance. The logo is also indicates certification of conformance to both ANSI Z 97.1 - 2004 and CPSC 16 CFR 1201. Each location is must provide routine samples to nationally recognized laboratories to verify compliance to industry and government standards. The application of our trade logo to each piece at the time of manufacture is your assurance and our guarantee of compliance. The permanent marking contains information regarding test standards, classification, thickness and branch location. Safety glazing logos must be visible and legible after installation to comply with national building and elevator codes. Trulite will not certify any certification of safety glazing by temporary label, shipping document, or letter. Using or installing any glass in hazardous locations not fully in compliance is unsafe and illegal.

Available in thicknesses from 1/8" to 3/4".

Heat-treated specifications.

Contact your local Trulite representative for further details.

Heat Treated

Title File
Tempered Glass Warranty
Fabrication and Heat-treated Guidelines
Strain Pattern
Glass Surface Staining
Heat-Treated Glass Comments
Cleaning Instructions TD-02-0402