Tempered glass has a surface compression no less than 10,000 psi (pounds per square inch), or an edge compression no less than 9,700 psi.
This glass type is extremely durable, often used to reduce the risk of accidents or break-ins. Fully tempered glass, which comes standard with our patio doors, garden and French doors, is four to five times stronger than ordinary float glass. Should the glass break, it falls out of the frame and shatters into small, harmless, pebble-like pieces without sharp edges.
This is by design, and an example of a well-tempered product, not a defective one. This fail-safe characteristic of tempered glass makes it an excellent product for safety glazing applications.