A Comparison: Bullet, Blast and Forced-­Entry Rated Glass

Bulletproof, blast-proof, and forced-entry glass are mainstays in the security industry. While they have very different use cases and performance standards, some products may be able to serve more than one purpose. When that’s possible depends on specific testing and product factors that we’ll outline in this article.

How Bulletproof, Blast-Proof, and Forced Entry-Proof Glass Work

Security glass products are called glazing in the industry. There are many different types of specialized glazing available; they have different compositions, but generally involve the lamination of different materials to create a product that can resist different types of force. Some common materials include glass, polycarbonate, acrylic, and laminating adhesives. 

Just because these products are similar does not mean they will all withstand any type of attack. Different glazing products are tested to specific standards, and rated to specify the minimum protection expectations, including the type of resistance to speed and penetration. These standards are a critical aspect of any security product. Other consumer goods might be able to make claims about performance without putting lives at risk. But, when you’re counting on glazing to protect people from an explosion or active shooter, having third-party verified products is critical to ensure product performance when it matters most.  

It’s important to note that no blast-, bullet-, or forced entry- resistant product will stop an attack indefinitely. Repeated shots, blasts, and blows will eventually break through. It may take minutes or hours, but it will happen. What makes these products helpful is that they buy time. If an aggressor can’t immediately get in, there’s time to pull the silent alarm, call the authorities, or get to a safe location. 

Below, we’ll discuss what makes each product unique. 

Bulletproof Glass

Bulletproof glass is designed to slow, deform, and stop a bullet. The specific construction of each bullet-resisting glazing panel depends upon the anticipated threat level. As the number of shots, bullet speed, and the bullet’s destructive profile increase, so does the protective level of the glazing need to increase.

Many bulletproof windows also offer impact protection against forces like hammers or hail because the ballistic glazing laminated-panel makeup is similar to forced impact panels. However, bulletproof glass is not always tested or rated to stop blunt force attacks or severe weather. The only way to truly guarantee bulletproof (and blunt-force) protection is to buy a rated product that is independently tested to a recognized standard.

UL 752 is the testing standard for commercial Bullet Resisting Equipment, including bulletproof glass. The specific UL rating indicates the number of bullets, bullet construction, velocity, and other factors it can be expected to stop when fired from a specific distance.

Blast-Proof Glass

Blast-resistance tends to have greater variation in use cases compared to other types of security glazing. First, there are many different types of blasts; different explosions created by different devices in different proximities have remarkably different effects. Second, blast rating standards are diverse, covering not just the effects of intentional detonations, but also unintentional detonations of fuels, gasses, oxidizers, reducing agents, and even finely powdered materials like flour and sugar in commercial and industrial settings. 

Blast-proof glass must also be able to protect people from the pressure wave that follows a bomb blast. In the event of a blast, shattered glass projectiles can cause extensive injuries, especially as the pressure wave can shatter glass beyond the immediate blast radius. Glazed blast-proof materials must eliminate glass shards (also known as spalling) and keep the system well-anchored to the wall. Even if the glass stays intact, if the whole window blows out of the frame, it can be incredibly dangerous. 

There are many standards for blast ratings; the most appropriate rating for your project depends on many different factors. To understand your options, speak with a security consultant. 

Forced-Entry Glass

A common type of forced entry-rated glass is one that meets the UL 972 Standard for Burglary Resisting Glazing Material. According to the UL 972 standard, forced-entry rated glass is designed “to resist burglarious attacks of the hit and run type.” Often, forced entry-resistant glass is made from glazed polycarbonate. 

A budget-friendly option that’s becoming increasingly popular are security window films. These films are often marketed as having both forced-entry and blast resistance. Security window films can fit into your overall physical security profile, but ensure that the manufacturer has independently tested the material to a known standard. Professional installation may also be required to ensure the system is anchored to the window frame, otherwise you may not get the protection you expect.

Which Security Glazing Product Is Right For You?

Various types of buildings and businesses require different levels of physical security. In order to determine what kind of physical security measures you need for your facility, you should start by performing a physical security risk assessment. Predicting the types of threats you expect, and deciding what measures are best to mitigate those threats, will help you plan out your steps for installation or retrofit.

Since bulletproof, blast-proof, and forced-entry resistance can involve different types of materials and costs, this distinction can be critically important to the planning process.

Can Forced-Entry or Blast-Proof Glass Stop Bullets?

Maybe. Unless glazing has been independently tested to an accepted industry standard, you have no guarantee it can stop a bullet. Determining the right glazing to use involves many factors, a few of which are whether people, critical infrastructure, or other property are located behind the area to be protected. It is always best to involve a knowledgeable physical security consultant to determine the right glazing type for your specific situation.

There is more force behind a bullet shot from a rifle than a hammer swung by a person. So while forced entry glass might be very strong, it simply is not designed to resist bullets. The same may be true for blast-proof glass. So, no matter what your concern is, make sure the product you choose has been tested to the appropriate industry standard. 

Learn More About Rated Glass and Physical Security

When human lives are at stake, it’s critically important that you have a clear understanding of the limitations of any product rated for bullet-resistance, blast-resistance, and forced-entry resistance. In these situations, we always recommend working with a security professional to fully understand whether the products meet your requirements and expectations. 

Every facility is different. The best way to get specific recommendations for your use case is to talk to an experienced professional. At TSS, we make sure we fully understand our customer’s requirements so we can offer the highest level of performance within the given constraints. Our extensive experience in the ballistic barrier industry has given us the knowledge to offer the best solution that fits your needs.

Learn more about our ballistic glazing solutions by downloading our free guide: Ballistic Glazing Solutions Guide. Or, reach out to our experts to learn more about how we can help you harden your physical security by contacting us. We’re happy to get to know you and your needs to determine which products are appropriate for your application.

 

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