Blast Resistant Classes

Blast-resistant glass is designed to achieve an ideal combination of stiffness and compressive strength of glass with the plasticity and energy-absorbing properties of polymer interlayers such as PVB. The designation Classes ER1, ER2, ER3, or ER4 depends on the corresponding amount of explosive pressure it is tested to withstand during simulations of an explosive detonation in a controlled shock-tube test mechanism. After testing, glass should remain in the test frame to prevent fragments from harming people on the protected side. Glasses can be classified as splintering or non-splintering. The non-splintering option means that, even in the event of an attack, there is less risk of injury to those in the immediate vicinity if the glass is broken: it does not splinter into sharp fragments but remains bonded to the interlayer. If there is no danger of injury to those nearby, the splintering option is a cost-effective alternative.