There are many kinds of glass with many different strengths. Our shower doors are offered in 3/8″ and 1/2″ thicknesses. Every shower door must be tempered. These doors are very strong and very safe. Tempering the glass not only strengthens the glass, but also adds an element of safety. If tempered glass ever breaks, it will shatter in a million tiny pieces – not large sharp pieces more typical of a broken window pane. We install thousands of frameless shower doors every year and have never had a single concern that the shower doors we build are unsafe.