How FEMA demonstrates the benefits of tempered glass

“FEMA’s guide shows an example of non-tempered glass that fell several stories from a multistory building in the form of large glass shards during the 1994 Northridge Earthquake.

Tempered glass will reduce the seismic hazard because it breaks into smaller fragments rather than large shards. According to the guide, tempered glass is required within 10 feet above a walking surface under some circumstances.

According to the guide, failures of this type can be very hazardous, especially if the glazing is located above exit ways. It also states that annealed, tempered, laminated and insulating glass units can pose a significant falling hazard if not designed to accommodate seismic forces and displacements. Glazing is especially vulnerable in flexible structures and in large storefronts because the windows occupy a large, structurally unsupported area at the ground floor. The guide recommends use of laminated glass for storefront windows to reduce seismic risk and to increase protection from burglary and vandalism in the aftermath of an earthquake.”