A Guide to Ballistic Standard UL 752 for Bullet Resistant Glass


Problem: Different buildings require appropriate protection from a variety of risks and threats.

Solution: Standardized ratings for bullet-resistant glass provides a guideline on the level of protection offered to make an informed specification decision.

It’s  quite common for us to encounter project specifications requesting “bullet proof glass”. However, as explained in one of our previous  blogs, there is no such thing as bullet-proof glass. Security glazing products in this class are known as bullet-resistant, ballistic-resistant, or BR glass.

Also, vital but commonly misunderstood, bullet-resistant glass is a range of glass products comprising of various thicknesses and formulas of glass, interlayer, acrylic and polycarbonate. It’s essential to specify what level of protection you require as this level of bullet resistance determines the makeup of the BR glass and specialized framing systems used to go into the protection of your facility.

UL 752 Protection Standards for Bullet Resistant Glass

When you are looking at incorporating ballistic protection solutions, the most common standard in North America is UL 752. Developed by UL Solutions, formally Underwriters Laboratories, this standard provides a reliable framework for people to have the same expectations about products that offer ballistic protection, including glass.. The test determines whether “protection is provided against complete penetration, passage of fragments of projectiles, or spalling (glass fragmentation) to the degree that injury would be caused to a person standing directly behind the bullet-resisting barrier.”

In addition, UL 752 also states “there shall be no opening of sufficient size to permit insertion of the muzzle of a standard weapon designed to use the ammunition used for the test completely through the glass”.

In layman’s terms, this means no part of the bullet or firearm can pass through the glass. Furthermore, it also means the person on the safe side of the glass won’t be sprayed with flying glass shards if the glass is shot.

The level of the bullet resistance determines how much protection the glass will provide based on the firearm, ammunition, and the number of shots, although the levels are not necessarily linear. For example, Levels 1 and 6 are very similar. Both use a 124 grain 9mm Full Metal Copper Jacket with Lead Core.. Level 1 has three shots; Level 6 uses five shots.  The difference between Levels 1 and 6 are two extra shots.

Some of the most common applications we see include retail, financial, police stations, military, corrections facilities, churches and data centers. As you can imagine, a jewelry store has much different needs than an embassy. According to Statista, handguns were the most commonly used weapon in armed robberies in 2021 with 37,899 robberies.There are a few reasons why that is and many of them are probably obvious. Handguns are very popular, easily accessible and also easy to conceal.

Private businesses and homeowners looking for protection from armed robberies involving handguns, improvised weapons, knives/cutting instruments, and blunt objects benefit from the security provided from Levels 1 – 3 bullet-resistant glass. Level 3 is one of USBP’s best selling product since it covers all handgun levels and most high-threat applications.

Government agencies and armed forces require additional protection against conventional terrorist weapons including bombs, explosives, and small to medium size infantry automatic rifles. These national security-type projects typically use a combination of blast-resistant and UL 785 Levels 4 – 8 bullet-resistant glass.

What Type of BR Glass Is Best For Your Project?

Level 1 Rating: Provides protection from small caliber handguns up to 9mm and is often used for gas stations, transactions windows, retail/convenience stores, and pharmacies.

Level 2 Rating: Provides protection from large caliber handguns up to .357 magnum and is commonly used in financial institution such as banks, credit unions, and check cashing businesses.

Level 3 Rating: Provides protection from large bore, large caliber handguns up to .44 magnum and is frequently specified in high-risk and high-occupancy public buildings, including school and government facilities as well as law enforcement, courthouse, and prisons.

Levels 4 – 8 Ratings: Provides protection against automatic weapons, assault rifles, and large caliber rifles. Levels 4 – 8 are normally only used in embassies, government facilities, and military applications.

See the following chart for a more detailed breakdown of UL 752 Levels 1 through 8. Once you have determined the level of protection suitable for your application, you can start determining the correct complete solution for your building design.

A proper threat and risk assessment would help determine exactly what level of protection your organization needs. Consulting with our team early in a project can save time, money, and ensure the glass, walls, and frames in your facility matches the security requirements necessary to protect it.

U.S. Bulletproofing is a pioneer in the design and supply of aluminum window and door systems that provide high-level protection from ballistics, blast, storm impact and forced entry. Our job is Protecting People and Property®, and we take that responsibility very seriously as evident in quality of products we provide and the scale and the iconic type of projects that have incorporated our solutions. Contact one of our sales representatives today to learn more about how we can help you with your next security project.