Commonly used to secure building or car windows, bulletproof glass is designed not to shatter when an object, such as a bullet, hits the surface. It’s often installed as an added security measure in homes, commercial buildings, schools, and government institutions.
Although it is referred to as “bulletproof,” bulletproof glass isn’t designed to be completely impenetrable to bullets. depending on the thickness and quality of the glass, some types of bulletproof glass will shatter with continual impact. These are some of the key myths and misconceptions you should know about bulletproof glass.
6 Common Misconceptions About Bulletproof Glass
1. No Type of Glass Is Completely Bulletproof
Despite the name, there is no such thing as bulletproof glass. While often marketed and portrayed as such, it’s more accurate to call bulletproof glass, “bullet-resistant.” Bulletproof glass can’t deflect bullets or objects. Instead, most of these products absorb the impact of bullets. While bulletproof glass will dissipate a bullet’s energy and prevent damage, certain objects and high-speed bullets can still break through its surface. Some types of bulletproof glass will even deflect a bullet or object.
2. Bulletproof “Glass” Often Isn’t Made of Glass
Because a normal pane of glass is unable to bend and absorb kinetic energy, it will instantly shatter when impacted by a high-force object, such as a bullet or sledgehammer. Many types of bulletproof glass are made from a combination of durable glass and plastic layers, while some are completely made of acrylic or polycarbonate. These film stacks help to absorb the bullet’s impact and prevent the window from shattering.
3. Objects Can Break Through Bulletproof Glass
Despite action movies with bulletproof cars withstanding non-stop rounds of bullets, it is possible for objects to break through bulletproof glass. This depends on a few factors, such as how the glass is made, what it’s made of, and how thick it is. Some types of bulletproof glass are susceptible to repetitive gunshots, blunt objects, and explosions.
4. There’s More Than One Type of Bulletproof Glass
Many people fail to realize that there are multiple types of bulletproof glass solutions. Some variations are made from layers of glass and plastic, while others are completely made of plastic. Other solutions, such as window shields or films, are designed to be applied over existing windows. These different types of bulletproof glass vary in cost and effectiveness, with more expensive solutions tending to be the most resistant to violent forces.
5. It Has More Use Cases Than Just Cars
While the term “bulletproof glass” typically conjures images of bulletproof cars and SUVs, this type of glass is also widely installed in commercial and government buildings, homes, and schools. It provides an extra level of security to any property, protecting people inside the space by keeping intruders and objects outside of the building.
6. It’s Legal for Businesses and Homeowners to Install
Some might think that bulletproof glass is only available for use by politicians and celebrities, but everyone can benefit from utilizing it as a security measure. It is legal for building owners to install bulletproof glass anywhere on private property in order to resist forces from bullets and break-ins. Whether you’re looking for added protection for your car or in your home, bulletproof glass is a valuable option to defend your property.
So, How Does Bulletproof Glass Work?
Glass is a fixed surface that cannot bend to absorb an object’s impact, which causes it to shatter when impacted by a bullet or other hard item. Bulletproof glass works by combining layers of plastic and glass so the plastic can absorb the object’s momentum, preventing it from going through the glass. The thicker the bulletproof glass, the more likely it is to be effective in stopping an object from breaching the barrier.
If bulletproof glass is hit with multiple rounds of bullets, it will likely have marks and cracks. High-quality glass solutions are designed not to shatter or allow the bullets to go inside, despite what damage to the exterior may be visible. It is important to keep in mind that bulletproof glass can change how much light enters a building or create optical distortions. For public buildings such as schools, however, these slight drawbacks don’t outweigh the safety benefits of installing thick, bulletproof glass.
The Different Types of Bulletproof Glass
There are many different variations of bullet-resistant glass commonly used to protect against damage to buildings and vehicles. Each variety differs in durability, cost, materials, usage, and quality.
Laminated Glass
This type of shatterproof glass was the first on the market. Laminated glass is made of a combination of glass and PVB plastic or resin interlayers. While less susceptible to shattering than glass, laminated glass is not completely bullet-resistant. The lamination prevents the glass from shattering inward, but it may not stop a bullet from entering a building.
- What is it made of? Laminated glass is made of glass and layers of PVB or resin.
- Durability: While more durable than regular glass, it is unlikely to prevent a bullet or blunt object from puncturing through the glass.
- Where is it used? Laminated glass is frequently used in vehicles, tall buildings, skylights, balconies, and frameless glass railings.
- Pros: It’s more challenging to break than regular glass, therefore it is useful as a popular security choice for homes and retailers, as well as helping to protect windows against hurricanes and natural disasters.
- Cons: Laminated windows are more expensive to repair than regular windows. They may not be able to protect against a determined intruder or a powerful explosion.
Acrylic
Acrylic glass is one of the most common types of bullet-resistant glass. This material is easy to cut and form into unique shapes, like curved windows. Acrylic is not noticeably different from glass, and is able to easily allow sunlight to pass through. Depending on the thickness, acrylic glass can protect buildings from bullets and blunt objects.
- What is it made of? Acrylic glass is made from a single sheet of acrylic. For better protection, multiple pieces of acrylic can be laminated together.
- Durability: Acrylic is usually resistant to impact and has 17 times the impact strength of glass.
- Where is it used? It can be installed in homes, churches, and commercial buildings.
- Pros: It’s 30 times stronger and twice as light as traditional glass. Acrylic glass is one of the more affordable options on the market.
- Cons: Acrylic glass is more likely to scratch than glass and isn’t heat resistant. Also, it doesn’t offer the highest level of ballistic protection.
Polycarbonate
Polycarbonate is a synthetic material that is made up of thermoplastic polymers that contain carbonate structures within their chemical makeup. Polycarbonate is particularly strong and durable.
In addition to being strong and durable it is lightweight, it is softer when compared to other bullet resistant materials. Because of polycarbonate’s softness, it can actually “catch” a bullet within the sheet. The material will not shatter into dangerous shards. As a result, the bullet will not ricochet around the interior protected space potentially causing further damage or injury.
- What is it made of? Polycarbonate windows and doors combine acrylic, PVB film and polycarbonate, made up of thermoplastic polymers containing carbonate structures in their chemical makeup. Sometimes, polycarbonate sheets are fixed to the outside of existing windows.
- Durability: Durable against blunt objects and bullet-resistant.
- Where is it used? Typically installed in commercial businesses and buildings.
- Pros: It provides a sturdy layer of fragment resistance, is lightweight, easy to cut and shape, and simple to install.
Glass-Clad Polycarbonate
Delivering superior protection against forced entry attempts, glass-clad polycarbonate is made of polycarbonate, acrylics, and other plastic resins. This bullet-resistant glass is more difficult to break than laminated glass. Designed to withstand firearm threats and bomb blasts, it’s one of the most durable bulletproof solutions on the market.
- What is it made of? Glass-clad polycarbonate is made of a combination of polycarbonate, plastic resins, and glass.
- Durability: It’s highly unbreakable and impenetrable. Likely to withstand firearm threats, explosions, and aggressive attacks.
- Where is it used? Installed in military or law enforcement vehicles, government buildings, courthouses, banks, schools, and stadiums.
- Pros: It will protect glass from gunshots, explosions, and blunt objects. Typically wears well and is used for exterior windows and doors.
- Cons: It’s one of the most expensive types of bulletproof glass. Glass-clad polycarbonate tends to have poor light transmission
Glass Thickness Impacts Bullet-Resistance
While the material of bulletproof glass certainly impacts its durability and ability to resist impact, the thickness of the glass can change its level of protection. To standardize glass protection ratings, the Underwriter’s Laboratory (UL) created a 10-level scale. They’re a global safety science company dedicated to research and standards development.
Most bulletproof glass provides Level 1 through Level 4 protection on the UL’s scale.
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- UL 752 Level 1 – Stopped three bullets from a small-caliber, 9mm handgun.
- UL 752 Level 2 – Stopped three bullets from a large-caliber, 357 handgun.
- UL 752 Level 3 – Stopped three bullets from large guns such as .44 magnums.
- UL 752 Level 4 – Stopped one bullet from a .30 caliber rifle.
See how the type and thickness of glass change its resistance to bullets.
Glass Laminate
- 1.185 Inches – Level 1 Protection
- 1.4 Inches – Level 2 Protection
- 1.59 Inches – Level 3 Protection
Acrylic
- 1.25 Inches – Level 1 Protection
- 1.375 Inches – Level 2 Protection
Polycarbonate
- 0.75 Inches – Level 1 Protection
- 1.03 Inches – Level 2 Protection
- 1.25 Inches – Level 3 Protection
Glass-Clad Polycarbonate
- 0.818 Inches – Level 1 Protection
- 1.075 Inches – Level 2 Protection
- 1.288 Inches – Level 3 Protection
- 1.338 Inches – Level 4 Protection
- 2.374 Inches – Level 8 Protection
Overall, glass-clad polycarbonate is the most bullet-resistant. Acrylic panels provide the least ballistic protection, while glass laminate and polycarbonate are ranked between Levels 1 and 3. However, notice that glass laminate must be much thicker than polycarbonate to maintain the same levels of protection.
What Can Break Bulletproof Glass?
As discussed above, the type and thickness of glass change how resistant it is to impact. But what objects can break bulletproof glass, and how quickly?
- Guns: Repeated gunshots can eventually cause bulletproof glass to shatter and break. However, it depends on the type of gun and how many shots were fired. While glass-clad polycarbonate is the most durable type of glass against gunshots, shots from certain caliber handguns and rifles may eventually wear it down.
- Sledgehammers: Sledgehammers can’t break polycarbonate or glass-clad polycarbonate, but they can shatter acrylic and laminated glass. However, it would take several minutes or even hours for someone to break it.
- Dynamite or explosives: Many types of bulletproof glass are resistant to explosives. If an explosive is detonated one or more times near the glass, however, it will eventually shatter. It’s important to note that these types of explosives are illegal for civilians to own.
What Does Bulletproof Glass Protect Against, and Who Should Install It?
Bulletproof glass provides an added layer of security to buildings, including religious buildings and detention centers. It’s an excellent way to protect people during active threats, such as a shooting or break-in. By preventing shattering glass and flying bullets from entering, it can keep people safe and give them time to call for help. The following types of buildings and institutions benefit from bulletproof glass:
Schools and Colleges
With school gun violence on the rise in the United States, security officials and schools are looking for new ways to protect students. Bulletproof glass is part of the answer. Laminated glass and window films can prevent windows from shattering and potentially slow down the intruder, however polycarbonate is the best defense against active shooters. It’s engineered to prevent both bullets and the shooter from entering the building. Bulletproof glass can also be installed in interior rooms as a double layer of protection.
Commercial Buildings
From retailers to banks, businesses are at high risk of break-ins. Regular glass makes it much easier for intruders to quickly break into and enter buildings. Bulletproof or shatter-resistant glass can help burglar-proof a building and make it more challenging for criminals to enter. With so many varieties of security films and bulletproof glass on the market, choosing to install is an easy solution for a building owner to improve the security of first-story windows and doors.
Government Buildings
Government facilities, such as embassies, courthouses, and law enforcement, demand very strict security measures. Many of these buildings require bulletproof windows and doors to protect occupants from bullets and projectiles. Government vehicles, such as police cars, may also have bulletproof windows and windshields to protect against gunshots.
Homes
Nowadays, even homeowners are installing bulletproof and shatter-proof glass in their homes to protect against intruders and natural disasters. Bulletproof glass is resistant to high winds and debris caused by thunderstorms or hurricanes. From front and back doors to first-level windows and garage windows, there are many different places homeowners can have bulletproof glass and window film solutions installed.
Cars
In addition to government officials and law enforcement, many celebrities and high-profile individuals are hiring professionals to install bulletproof windows and windshields in their cars. While it’s more costly than regular glass, bullet-resistant glass can be life-saving if dangerous situations arise.
Want to Protect Your Home or Business with Bulletproof Glass?
If you’re interested in installing a bullet-resistant or shatter-proof solution in your home, business, or workplace, Window Film Depot has a variety of innovative solutions. Learn more about some of our top-rated ballistic protection solutions.
1. BulletShield™ Ballistic Panel
Sometimes called the “body armor for windows,” our BulletShield solution is a protective system designed for existing windows and door glass. It’s a security shield made out of clear polycarbonate and mounted over the existing glass. This polycarbonate glazing makes windows and doors incredibly bullet-resistant. It’s independently tested and proven to prevent breach against 9mm, .44 magnum, and AR-15 bullets. This solution is ideal for schools, government buildings, courthouses, police stations, and businesses.
2. DefenseLite™ Forced Entry Glazing Solution
DefenseLite is our patented security shield designed to mount onto and reinforce existing glass windows and doors. This solution is a heavy gauge polycarbonate and extruded framing solution. Tested against batons, hammers, and hatchets, this solution withstands blunt objects and force. DefenseLite is a durable and economical protective measure for businesses, schools, and storefronts.
3. 3M™ Scotchshield™ Safety & Security Window Films
The 3M Ultra Series films are made from clear, tear-resistant film. They’re designed to protect windows from outside dangers and deliver superior performance in blast and impact events. These films are also available in a variety of tints for added privacy. This solution is best for residential homes and some businesses.
Want to learn more about one of our innovative bullet-resistant solutions? Contact our team today and discover how to improve your home’s or business’s security against ballistics. Family-owned and operated since 1992, we’ve been named the number one installing window film dealer in the United States by Window Film Magazine for four consecutive years. Let us help you find the best solution to keep your family, students, or colleagues safe.