Are You Safe behind a Bulletproof Glass? All you wanted to know about a Bulletproof Glass

Posted on : 12-03-2022    Author : Janani Kesavan

Did you know that bulletproof glasses are not actually bulletproof? All types of glasses shatter and break at some point of time. But bulletproof glasses create resistance and dissipate the bullet’s energy while still providing optical transparency, thus saving human lives. That is how bulletproof glasses work. For this reason, the industrial term for bulletproof glass is bullet-resistant or ballistic glass.

What is Bulletproof Glass?

An ordinary glass offers no protection against bullets, as it does not absorb the bullet’s energy and force. Therefore, an ordinary glass shatters and the bullet continues to move on its course.
On the other hand, a bulletproof glass which looks just like an ordinary glass, is able to absorb a bullet’s energy and force by spreading it sideways through different layers of glass that are present in it. The bullet slows down and loses its energy and momentum. In simple words, a bulletproof glass can be described as a safety glass that absorbs energy and can be more aptly called bullet-resistant glass.
It is important to note that tempered glass or toughened safety glass is not bulletproof glass. Toughened safety glass is sensitive to sharp objects and thus, cannot provide protection against even the tip of a bullet. It will simply shatter into smaller pieces on impact.

How is Bulletproof Glass Manufactured?

Bulletproof glass is made by a process called lamination, in which pieces of bulletproof materials like special polycarbonate, acrylic plastics and glass-clad polycarbonate are layered in-between pieces of non-tempered soft glass. Both polycarbonate and acrylic give high tensile strength and maximum optical clarity. Sometimes, lightweight thermoplastic polyurethane layers which offer the highest protection are also used. These alternating layers of plastic absorb the force from an impact and offer different levels of protection. Here, the thickness of the glass is of utmost importance.
The specifications for the 8 levels of resistance are as follows:

• Level 1: With a thickness of .75 inches, this glass provides protection against small calibre handguns. For example, three 9mm bullets. This is used in small businesses to prevent simple theft, an armed robbery and crime.
• Level 2: With a thickness of a little more than an inch, this will provide protection against threat of fire from large calibre handguns, such as three .357 Magnum rifle bullets. This is used in buildings such as banks, petrol bunks and jewellery shops.
• Level 3: With a glass thickness of 1.25 inches, there is a higher protection even against powerful revolvers. Low-level government buildings and police stations use this glass.
• Levels 4-8: As the levels increase, the bulletproof glass has a higher number of polycarbonate plastic. Thus, the glass becomes thicker, heavier, more durable and offers greater levels of protection. These glasses are mostly used in high-level government buildings and the military.

Difference between Bulletproof Glass and Laminated Glass

Bulletproof glass and ordinary laminated glass are different. All bulletproof glass is laminated, but all laminated glass is not bulletproof. For example, though your car windshield is laminated, it is not bulletproof; only impact-resistant to a certain degree. In a ballistic glass, the exterior glass panels provide raw strength and the inner laminated layers provide flex strength. Put together, the layers in ballistic glass offer protection against impact from any projectile.

Are You Safe behind a Bulletproof Glass?

Yes, to a great extent. However, it is dependent on the type of weapon used, the thickness of glass and its resistance level. Thicker the glass, greater the ballistic protection it offers.

Making Bulletproof Glass at Home

Today, there are many Do-it-Yourself (DIY) articles and videos floating around on social media that tell you how to make a bulletproof glass at home. However, ensure that while choosing a bulletproof glass, you get an expert opinion and choose one that offers high light transmission and practical suitability.
You should only buy trustworthy ballistic glasses that are made by expert glass manufacturers across India.