The word “bulletproof” is often used synonymously with “indestructible” or “impenetrable.” In that context, you may wonder about the strength of bulletproof windows. So can you break bulletproof glass?
Bulletproof glass will almost certainly fail at some point. When struck enough times with the right object with the right amount of force, or if you fire continuously, the glass will eventually break. This is true for any physical security barrier product. However, because bulletproof glass is incredibly strong, it’s difficult to “break” in the way you would break non-rated glass. Bulletproof glass typically contains adhesives and materials that hold the glass together, even when it’s been shot.
It’s also important to remember that bulletproof glass isn’t supposed to be impenetrable—the goal is to slow an attacker down to give the authorities time to arrive and de-escalate the situation. In this blog, we talk about different levels of protection bulletproof glass offers, what might cause it to fail, and how to be certain you’re getting the right protection for your facility.
A Note on UL 752 Levels of Protection
Before we talk about what can break bulletproof glass, we need to clarify that not all bulletproof glass is the same. UL 752 is a testing standard for ballistic barriers. Bulletproof glass can be tested or rated to levels 1 through 10, although Level 8 is the strongest bulletproof glass that is typically used in commercial construction.
Levels 1 through 3 can withstand a tight cluster of three shots from different pistols. This level of protection is common for convenience stores, financial institutions, and healthcare settings.
Levels 4 through 8 are for various protection from rifles, including a .30-06 hunting rifle up to an AR-10 semi-automatic rifle. The highest levels of protection are typically used in federal government facilities and military installations, but are becoming more common in schools.
For a better understanding of the differences in the protection levels, we have a video demonstrating live fire ballistic resistance in different types of bulletproof glass.
What Might Cause Bulletproof Glass to Break?
As with any physical security products, bulletproof glass is not indestructible. With the right tools and unlimited time, an aggressor can successfully breach bulletproof glass. The question is how long it will take, and what actions can be taken to save innocent lives. After all, the point of bulletproof glass is to buy time for authorities to arrive and organize a defensive stance.
Here are different ways bulletproof glass can fail:
- Multiple rounds hitting the exact same spot: Bulletproof glass incurs damage as it disperses the energy from a bullet, leaving it vulnerable to repeated shots in the same location. However, the likelihood of a bullet hitting the same spot twice is low.
- Powerful tools not included in the UL 752 standard: While the UL 752 standard is the industry gold standard, not every bad actor uses a weapon that’s included in its parameters. In 2023, a thief used a backhoe to break bulletproof glass and steal cash from an ATM. You can see a bowling ball shot out of a cannon puncture some of our bulletproof glass in a How Ridiculous video. Thankfully, these are extremely unusual situations.
- Weak or no framing: Bulletproof glass is thicker and heavier than standard glass, so it often requires special framing systems to keep it from blowing out when shot. Even “floating” designs are carefully engineered to withstand the force of an attack, so skipping framing puts your glazing at risk of failure, simply because there isn’t enough support. While this isn’t the same as bulletproof glass breaking, it’s an important safety factor to consider.
- Blunt force attacks: Not all ballistic glass is rated for forced entry, but in most cases a forced-entry attempt will require significant time and strength. For instance, we offer trade show attendees the opportunity to try and break some of our bulletproof glass with a hammer when they visit our booth, and they can’t do it.
When you complete your due diligence, speak with a security expert, and conduct a thorough threat assessment, you can rest assured that the ballistic barrier you choose will provide the right protection for your needs.
Talk to TSS Security Experts Today
If you are ready to harden your physical security, but you have concerns about the breakability of bulletproof glass, talk to TSS to learn more about how our products perform. Our team has decades of experience manufacturing and installing ballistic barriers in all types of buildings. We can guide you to the right product for your needs, including products with forced-entry and blast protection.
For more information, you can read our recent post on a comparison of bullet, blast, and forced-entry rated glass. Or, for a more personalized recommendation, or to talk with a security expert about ballistic protection, please fill out our online contact form. We’re ready to help you understand how ballistic barriers can help secure your facility and personnel.