Fully tempered glass and spontaneous fracture
September 24, 2025
Fully tempered glass offers designers certain advantages over annealed and heat-strengthened glass, including increased strength to resist imposed loads and thermal stresses, as well as a characteristic breakage pattern in a “relatively safe” manner; however, these features come at the cost of increased optical distortion and an often overlooked risk of spontaneous breakage in-service due to nickel sulfide inclusions.
By Christopher J. Brandmeier, PE, John A. Jackson, AIA, and Thomas A. Schwartz, PE