Bullet resistant glass is an important feature of safety, particularly if you’re dealing with anything related to bank security. The experts at Minuteman Security have carefully crafted these six important features you should consider with your purchase.
How Does This Type of Glass Work?
To really appreciate the features of glass that is resistant to bullets, it helps to understand the science behind it. To do this, it helps to take a look at why ordinary glass shatters. It all has to do with the exertion of force.
Why Regular Glass Breaks
If you can absorb the energy gradually, it causes less of a “pain point” on the material.
Because regular glass is stiff and doesn’t move, if someone fires a bullet at it, it can’t absorb the energy in a gradual fashion. That’s why it shatters–it’s because the bullet is able to continue without losing any momentum.
But what if we could tweak the way energy is distributed throughout the glass? Now you’re getting into the basic physics of how this specialized type of glass works.
How Glass Can Be Bullet-Resistant
Bullet resistant glass has multiple layers–the glass is interlaced with various plastics. These are very tough types of plastics, one of which is called polycarbonate. This prevents the glass from “spalling,” a situation where pieces of glass or plastic splinter off and could possibly injure a bystander.
Therefore, when a bullet his it, the energy from the bullet spreads sideways and travels through the layers. This means the energy is “divided” throughout the glass instead of in one specific point. Some people find it easier to refer to this resistant glass as “energy-absorbing” glass because this term provides a good explanation for how it works.
What Are Some of the Advantages of This Type of Glass?
First, it adds a layer of extra security and deals away with the headache when you can’t remember a combination or a combination is not working. There are also times when electronics may not be working on bank equipment, and this can be an easy fix.
6 Important Features to Consider with Bullet Resistant Glass
Now that you have a basic understanding of how this kind of glass works with the laws of physics, it’s time to take a look at some important things you should consider when purchasing it.
1. What Is the UL Rating?
The UL rating is of vital importance if you’re considering purchasing glass, which is bullet resistant. Following is the information you need to know about it.
The UL stands for Underwriter’s Laboratory. This is a non-profit organization whose purpose is to help public safety, and it does so by establishing standards for various products. This ensures that they are safe if they adhere to these standards.
The UL system lists 8 levels of glass that is resistant to bullets.
UL System Level 1
This includes all glass that can withstand bullets from handguns of small caliber. To qualify for this designation, the glass must be able to resist three 9mm bullets traveling at around 1, 175 feet a second.
UL System Level 2
Level 2 takes things a step further and means the glass is able to withstand larger caliber fire from handguns. This means it must stand up to three shots of .357 magnum soft points. These bullets travel at a speed of 1,250 feet per second.
UL System Level 3
This takes the standards level a bit higher, as this glass withstands a minimum of three shots of .44 magnum rounds. These bullets can travel at a speed of 1350 feet per second.
UL Level 4
Here we see a dramatic uptick in the strength of the bullet resistance of the glass. Glass with a UL rating of 4 can withstand one shot from a .30 caliber rifle. These have a minimum velocity of 2540 feet per second.
UL Level 5
This includes glass that can withstand one 7.62 rifle FMJ that has a velocity of at least 2750 feet per second.
UL Level 6
Again, this takes protection to the next level, as it is able to withstand five 9 mm rounds at a speed of 1400 feet per second.
UL Level 7
This glass remains intact after receiving multiple hits with 5.56 rifle FMJ at a velocity of 3080 feet per second.
UL Level 8
This is the highest level of protection that is available in this type of glass that can resist bullets. It is tested to withstand five shots from a 7.62 mm rifle.
Usually, UL levels 4 through 8 are typically used by the military for applications that could possibly involve gunfire from heavy caliber equipment.
2. Ask About UV Protection
Did you know that glass that is resistant to bullets can ultimately be affected by exposure to UV radiation of sunlight? It’s not unusual for it to also be affected by temperature and exposure to solvents.
This is due to a polycarbonate layer that we mentioned earlier. Over time this can become brittle because it is amorphous–in other words, it is necessary for it to be amorphous in order for it to be transparent.
3. What Type of Frame Does It Use?
Does it use a stainless steel frame? This is an important question to ask if you’re considering purchasing glass that is resistant to bullets.
4. Ask About the Benefits of Acrylic Security Glass
One of the advantages of acrylic glass is that it can have greater durability, meaning it can resist solvents and last longer in rough weather. In addition, it’s also more resistant to ultraviolet light that comes from sunlight. Acrylic security glass has a UL rating of 1 and 2.
5. Can the Glass Fit Into Existing Frames?
In many cases, this depends upon the specific ballistic material. However, in general, it can be retrofitted to slide into an existing frame. It’s also important that the framing is tested as well to ensure that you have the complete protection you need and deserve.
6. How Clear Is the Glass?
The amount of clarity you need depends largely upon the scope of your services. For example, if you have a window that involves human interaction–like a bank transition window–then it would be beneficial to have a clearer type of class. This is one reason why acrylic glass has the most clarity.
Minuteman Security Offers the Best in Security Glass Design
When it comes to your security, you can’t trust just anyone. That’s why the experts at Minuteman Security have everything you need to establish and maintain a secure, safe system.
Do you need to replace obsolete or broken equipment? Maybe you need the experienced consultation of experts who have more than 40 years of experience.
Minuteman Security has no equal when it goes to the knowledge of the product and the quality of service. We have over $2 million insured and have a Class C license from the Texas Department of Public Safety. This means we are licensed to do alarms, video, and security consulting. For bullet-resistant glass design, sales and repair, contact Robert at (800)913-1237