UL 752 Levels Explained: Bullet-Resistant Ratings 1 to 10

If you are specifying a bullet-resistant wall, counter, door, or window for a bank, courthouse, school, pharmacy, or guard booth, the rating you will see on almost every product data sheet is UL 752. It is the standard most U.S. architects, security consultants, and building owners use to describe how much ballistic protection a fixed barrier provides. This guide walks through what UL 752 is, what each level means, how testing works, and how to avoid the most common mistakes buyers make when reading a rating.

What UL 752 Is

UL 752 is the Standard for Bullet-Resisting Equipment, published by UL Standards & Engagement and used by UL Solutions and other laboratories to test materials and assemblies. The current edition is the twelfth, issued in 2023 and available through the ANSI webstore. It covers equipment intended to protect people behind it, such as wall panels, glazing, transaction windows, doors, and fiberglass or composite armor, rather than armor that a person wears.

That last point matters. Body armor in the United States is rated under the National Institute of Justice system, which we cover in our guide to NIJ ballistic armor standards. UL 752 is the architectural counterpart. The two systems use different ammunition, different shot counts, and different pass criteria, so a level number in one does not translate directly to the other.

The UL 752 Levels at a Glance

UL 752 defines eight core levels, two higher rifle levels, and a supplementary shotgun rating. The table below summarizes the threat for each level as it appears in published UL 752 test summaries. Velocities are the minimum test velocities.

The standard itself describes each level in plain terms. Level 1 is protection against medium-power handguns such as the 9mm. Level 2 covers high-power handguns such as the .357 Magnum. Level 3 covers “super power” handguns such as the .44 Magnum. Level 4 addresses high-power hunting and sporting rifles such as the .30-06. Level 5 covers military ball ammunition from a .308 class rifle. Level 6 addresses multiple shots from a submachine gun such as a 9mm Uzi. Levels 7 and 8 address multiple shots from military rifles in the M-16 and M-14 classes respectively. Level 9 moves to armor-piercing rounds.

Why the Numbers Are Not a Straight Ladder

A common assumption is that a higher number always means more protection against everything below it. UL 752 does not work that way. The levels were added over time to describe specific threats, so the sequence is not strictly cumulative.

• Level 6 is a handgun-caliber level. It uses the same 9mm projectile as Level 1, fired faster and five times instead of three. A Level 6 product is not rated for any rifle round.
• Levels 4 and 5 are single-shot rifle levels. They test against one rifle round. Levels 7 and 8 test five-shot groups, which is a much harder test because each impact weakens the material around it.
• Level 8 and Level 5 use the same round. The difference is the shot count: one shot for Level 5, five for Level 8.
• Level 3 is often the minimum for handgun-heavy environments. Many retail and public-facing installations specify Level 3 because it covers common handgun calibers up to the .44 Magnum. That is a design choice made by a security professional, not a requirement of the standard.

The practical takeaway: when you compare products, read the threat description, not just the number. If your risk assessment includes rifles, a Level 3 or Level 6 product is not the right comparison, no matter how robust it looks.

How UL 752 Testing Works

UL 752 testing simulates a close-range attack. Published UL test records describe samples mounted in a rigid frame and fired at from approximately 15 feet. Behind each sample, at roughly 18 inches from the protected face, the lab places a thin corrugated cardboard indicator panel, sometimes called a witness panel.

For multi-shot levels, the shots are placed in a tight square pattern in the center of the sample. For Levels 6, 7, and 8 that pattern is 4.5 inches on a side. The pass criterion is the same at every level: no penetration of the projectile through the sample, and no spalling from the protected side to the extent that fragments embed in or damage the indicator. You can read more about the general process on the UL Solutions bullet-resistant materials testing page.

The spall requirement is the part buyers most often overlook. A barrier that stops the bullet but throws sharp fragments off its back face can still injure the person it is supposed to protect. That is why backing layers and spall control show up so often in bullet-resistant design, and why coatings and liners play a role in many assemblies. Our article on spall liners covers that subject in more depth.

Material Rating vs. System Rating

A sheet of fiberglass armor tested at Level 3 tells you how that sheet behaved in the lab. It does not tell you how a finished wall performs if the panel joints are not overlapped or backed, if outlets and conduit penetrate the panel, or if the door frame next to it is hollow metal. Attackers do not aim at the center of a panel; gaps, seams, and frames are where installations fail.

When you evaluate a project, ask these questions:

• Was the material tested alone, or was the complete assembly (panel, framing, fasteners, finish, and joints) tested?
• Are seams covered with battens or overlaps rated to the same level?
• Are doors, frames, glazing, and transaction drawers rated to the same level as the walls?
• Are penetrations for electrical, data, and HVAC protected?
• Does the threat assessment that drove the level selection still reflect the site?

The Glass Association of North America has a useful technical bulletin on bullet-resistant glazing that discusses how glazing ratings relate to the frames around them.

How to Verify a UL 752 Claim

UL 752 compliance is voluntary, and the wording on marketing materials varies. “Tested to UL 752,” “meets UL 752,” and “UL Listed” are not the same thing. A listing means the product appears in UL’s certification directory and is subject to follow-up inspection. A test report means a sample passed on a given day.

To verify a claim:

1. Ask the manufacturer for the UL file number or certification number and the exact model and level.
2. Search the UL Product iQ certification database for that file number.
3. Confirm that the model, thickness, and level in the listing match what is being quoted for your project.
4. If the product is only “tested to” the standard, ask for the full lab report, including the lab name, date, sample construction, and shot results.

UL also published an accessible overview, What Does It Take to Stop a Speeding Bullet?, that explains why verification matters.

UL 752 and Coatings

Readers often ask whether a sprayed coating such as polyurea can carry a UL 752 rating. A coating by itself is a thin elastomer and is not a bullet-resistant barrier at any UL 752 level. What coatings can do is form part of a tested system: for example, as a bonded layer on a fiberglass, steel, or composite panel, where the coating helps hold the substrate together and manage fragments. Any rating applies to the full system that was tested, with the specific substrate, thickness, and coating in the test report. We explain the limits and the real uses in Is Bulletproof Paint Real? and in our earlier piece on polyurea and ballistic threats.

Choosing a Level: A Practical Approach

There is no single correct level for a building type. The choice should come from a threat and vulnerability assessment by a qualified security professional. That said, the process usually follows these steps:

1. Identify the realistic threat. Handguns only, or rifles as well? Single shots or sustained fire?
2. Map the protected area. Which walls, counters, doors, and windows actually separate people from the threat?
3. Select one level for the whole envelope. Mixing a Level 3 wall with an unrated door leaves the door as the path of least resistance.
4. Check structural capacity. Higher levels mean heavier panels and glazing, which affects framing, anchors, and hardware.
5. Verify ratings and installation. Confirm listings and have the installer document seams, penetrations, and frames.

For more context on how rounds behave when they hit a target, see our pages on terminal ballistics and ballistic testing. If you are comparing panel materials for a wall build-out, our guide to bullet-resistant panels and materials covers the trade-offs.

Key Takeaways

• UL 752 is the main U.S. standard for bullet-resisting equipment such as walls, glazing, doors, and counters.
• Levels describe specific threats and shot counts; a higher number is not always “more” protection against every round.
• Passing requires no penetration and no damaging spall reaching an indicator about 18 inches behind the sample.
• Ratings belong to the tested product or system, so verify listings and protect seams, frames, and penetrations.
• Coatings are not rated barriers on their own but can be part of a tested assembly.