A Brief Lesson on Bulletproof Glass

We use this blog most often to inform our current and potential customers about the replacement window and door products we sell in San Diego. But this time, we wanted to do a “just for fun” post about something of interest to those of us in the glazing industry, even though it’s a product we don’t sell at BM Windows: bulletproof glass. Hopefully you’ll find it interesting too, and maybe learn something new!

Bulletproof glass is a specialty glass that could more accurately be called “bullet resistant glass.” No glass is completely bulletproof, but most products out there will keep bullets from penetrating the glass altogether, or at least slow them down to minimize the damage that can be done by bullets. You will find bulletproof glass used most often in places like banks, retail stores, schools, government buildings, and armored vehicles—all places that require an extra layer of security.

Bulletproof glass was first patented in France in 1909 by Edouard Benedictus, a French chemist. By 1914, the United States was using bulletproof glass to protect soldiers during World War I. It was incorporated into military equipment such as gas masks, aviation goggles, and airplane windshields. Also around this time, bulletproof glass was beginning to be installed in banks to protect tellers, but it wasn’t until 1942, after the bombing of Pearl Harbor, that bulletproof glass was installed in the Oval Office.

Most bulletproof glass is made using a process called lamination, which uses multiple layers of glass and plastic. The glass is tempered, which means it has gone through either a chemical or heat treatment that strengthens the glass. Tempered glass can be found in other places, like in the replacement patio doors sold by BM Windows, and in car windshields. It is not bullet resistant on its own, but when multiple panes of tempered glass are combined with layers of plastic, it creates a product that is able to absorb the energy from almost any bullet, and to keep it from penetrating all of the layers and causing damage to whatever is on the other side of the glass.

If you’re interested in seeing someone try to penetrate bulletproof glass with various types of guns and calibers of bullets, take a look at this fun video from a gun enthusiast out of Texas who puts the glass to the test:

As the above video shows, it takes quite a powerful weapon to completely penetrate bulletproof glass, but it isn’t impossible.

Hopefully your San Diego home doesn’t have a need for bulletproof glass, but if you are in need of replacement windows or patio doors, BM Windows would love to help you select the products that best suit your needs. Our replacement window and door products may not be able to withstand a bullet, but they will make your home more energy efficient, and give it a brighter, and more updated look and feel.

Contact us today to schedule a free, in-home consultation with one of our friendly, knowledgeable BM Windows representatives, who can answer all of your questions about replacement windows and doors for your San Diego home and provide you with an estimate for your project.