Fun fact: bulletproof glass was invented by accident in the 19th Century by a scientist working on high-quality adhesives. He knocked over a flask of polymer when climbing a ladder, which fell but didn’t spread into splinters when shattered. He observed the effect and went on to manufacture one of the most curious inventions of the century. Although bulletproof glass for cars would not be seen until after the First World War, one cannot deny the significance it holds for modern armoured vehicles. We have come a long way in terms of technology for bulletproof glass, so much so that it is now easier to manufacture and utilize among urban environments.
Thus, it is natural to wonder what exactly is the difference between bulletproof glass and regular glass. Sure, windows of bulletproof cars are an obvious example where this type of glass can be used, but since such vehicles often rely on being discreet with their capabilities, it is hard to be sure. In light of that, here is a complete list of distinctions between bulletproof glass and regular glass.
- Bulletproof Glass Has Plastic
Okay, let’s get the obvious out of the way. Bulletproof glass is not all “glass”. It is made of several sheets of polymer, usually high-density polycarbonate, that is sandwiched between the glass layers. Glass is made of molten silica, a raw mineral most commonly found in sand. When manufacturing bulletproof glass for cars, the polymer sheets are heated and laid over the glass panels. This is done to bond the molecules together and settle the sheets and glass as one piece when it cools down. Regular glass is simply shaped the way you want from molten silica.
- Bulletproof Glass is Thicker
Due to the thickness of polymer sheets in the mix, glass in armoured vehicles is thicker than that in regular cars. This is also the reason why the armouring process of a vehicle involves removing window panes and doors to make a wider girth to accommodate the bulletproof glass. Moreover, the thickness of the BR glass can vary depending on the armouring level, going up to 42 mm for CEN BR6 grading. Regular glass, on the other hand, is slim. Most glass in vehicles today is shatter-proof, so it does have some level of protection. Still, BR glass exists for a reason. You can’t expect regular glass to stop a bullet, can you?
- Normal Glass is More Transparent
Naturally, nothing is more visible than anything. This is why glass in the window of a bulletproof car is difficult to look through. This provides an additional advantage to the occupants because the glass restricts any outside surveillance, especially in low-light conditions. Since there is no distortion in the material, normal glass is easier to see through. It is used in the windows for most outlets due to this property. You want the customer to know what kind of stock is in store with just a glance, unlike an armoured car that prevents you into looking whether the passengers are armed or not.
- Bulletproof Glass Is Elastic
Elasticity is the property of a material to stretch under stress without breaking. Since bulletproof glass needs to absorb the kinetic energy from the projectile, it needs to be highly elastic to do so. Ever caught a cricket ball in the palm of your hand outstretched? Imagine that just 12 times faster. The polymer sheets within the glass layers slow down the bullet so that when it hits the brittle glass on the inside, it feels more like a small rock thrown than an actual bullet shot at the car. On the flip side, the glass in regular vehicles is prone to shattering when hit with a high-velocity round. It is not only dangerous because of the bullet but also because of the several shards of glass that is now all around the interior of the car.
- Normal Glass is Less Expensive
Now, in the light of the new materials that are used to manufacture BR glass, it is no surprise that the complicated process makes it more expensive. A sample of glass in armoured vehicles just a few millimetres thicker than the same cross-section as regular glass can cost five times more. Moreover, the process to replace damaged pieces also costs more money and time. This is also because panes for regular glass don’t bear that much of stress from the rest of the structure, while in case of BR glass, the entire section should be removed to resolve any compromise.
Must Read:- What factors make the Toyota Vellfire most suitable as an armoured vehicle?
Glass in armoured cars is a true testament to modern engineering. So much so that many of the engineers, designers, and executives actually test them by taking cover behind them during testing. If you ask me, that is a dangerous way of marketing, although it does solidify the fact that such a technology is dedicated to preserve and protect lives. Beautiful showpieces are surely soothing to look at but an actual human life is something that you can never put any mone
