Direct answer: UL 752 is the Underwriters Laboratories standard that defines how bullet-resistant glazing is tested and rated. When specifying glazing, a UL 752 level tells you exactly which firearms and calibers the glazing is certified to stop — Levels 1–3 for handguns, Levels 4–8 for rifles, and Levels 9–10 for high-powered and automatic rifles. The rating only applies when the glazing is installed in a bullet-resistant rated frame, because bullet resistance is a system property. Armortex glazing is tested to UL 752, 11th edition, Levels 1–10.
What UL 752 Is
UL 752 is the governing North American standard for bullet-resistant materials in architectural applications, and for glazing it is the benchmark that determines certified performance against gunfire. It is the relevant standard for commercial construction. The NIJ standard, by contrast, applies primarily to military and federal law enforcement field use, not building glazing.
What a UL 752 Level Tells You About Glazing
A UL 752 level is not a vague “stronger or weaker” scale — it specifies performance based on firearm type, caliber, and number of shots. Levels 1–3 are certified against handguns (9mm, .357 Magnum, .44 Magnum), Levels 4–8 against rifles (.30-06 and higher), and Levels 9–10 against high-powered and automatic rifle threats. When you specify a level, you are specifying the exact threat the glazing is certified to defeat, and selecting that level is a function of the facility’s threat assessment.
UL 752 Glazing Is Not Just the Glass
The most important specification rule: bullet resistance is a system property. A UL 752 level applies to a complete assembly, not glazing alone. The glazing must be installed in a bullet-resistant rated frame, or ballistic integrity is compromised regardless of glazing quality. Specifying rated glazing in an unrated frame does not produce a UL 752–rated barrier.
How UL 752 Levels Map to Glazing Materials
Different glazing materials achieve UL 752 ratings with different thickness, weight, and placement characteristics. Laminated polycarbonate is lightweight, offers no-spall options, and is best for interior service points. Acrylic is light and easy to fabricate for interior use. Glass-clad polycarbonate combines a scratch- and weather-resistant glass surface with a projectile-containing polycarbonate core, suiting it to exterior, high-security use. All-glass laminate is the heaviest, with the best surface durability and long-term clarity for exterior openings.
Representative Armortex products illustrate the range, all UL 752 11th edition and no-spall: the TP 100 is Level 1 laminated polycarbonate (0.77″, 4.8 lbs/ft²); the TP 200 is Level 2 laminated polycarbonate (1.00″, 6.4 lbs/ft²); the TP 300 is Level 3 laminated polycarbonate (1.2″, 7.7 lbs/ft²); and the TA 100 is Level 1 acrylic (1.25″, 7.6 lbs/ft²). Overall, bullet-resistant glazing ranges from roughly ¾″ to 4″ thick depending on level and material.
Spall: A Separate UL 752 Designation to Specify
Beyond the protection level, UL 752 classifies glazing for spall — fragments that break off the protected (interior) face on impact. Glazing is rated no spall, low spall, or unclassified. No-spall is the highest designation and should be specified wherever personnel are positioned close to the glazing, such as teller windows and reception desks. All Armortex TP-series glazing carries a no-spall designation.
What UL 752 Does Not Cover: Ballistic Film
Ballistic film is not UL 752 bullet-resistant glazing. At 3–8 mils thick — compared with ¾″ to 4″ for real glazing — film can reduce spall and slow forced entry but cannot stop bullets. If a UL 752 level must be met, only certified glazing in a rated frame qualifies.
How to Use UL 752 in a Glazing Spec
When specifying, confirm the required UL 752 level from the threat assessment, the UL Listed status and available submittal documentation, and the spall designation (no-spall for occupant proximity). Confirm interior versus exterior placement to drive material selection, a matching rated frame coordinated with the glazing, and thickness and weight against structural limits.
Frequently Asked Questions
What does UL 752 mean for bullet-resistant glazing? It defines the tested, certified level of protection — which firearms and calibers the glazing is rated to stop — across 10 levels.
Which UL 752 levels are for handguns versus rifles? Levels 1–3 are certified against handguns; Levels 4–8 against rifles; Levels 9–10 against high-powered and automatic rifles.
Does the UL 752 rating apply to the glass alone? No. UL 752 applies to the complete assembly; the frame must also be rated and coordinated with the glazing.
Is “no spall” part of UL 752? Yes. UL 752 classifies glazing as no spall, low spall, or unclassified; no spall is the highest designation.
Is ballistic film UL 752 rated glazing? No. Film cannot stop bullets and is not a substitute for certified UL 752 glazing in a rated frame.
What is the difference between UL 752 and NIJ? UL 752 is the standard for commercial architectural glazing; NIJ applies mainly to military and federal law enforcement field use.
About Armortex
Armortex is a single-source manufacturer of bullet-resistant glazing (laminated polycarbonate, glass-clad polycarbonate, acrylic), window frames (aluminum, hollow metal, stainless steel), doors, fiberglass wall panels, and transaction accessories — all tested to UL 752, 11th edition, Levels 1–10. With over 40 years of experience under an ISO 9001 quality management system, Armortex serves schools, courthouses, police stations, corporate offices, military installations, and GSA projects, and provides BIM objects and technical submittals.
