Can any security glass also be fire-rated?>
Can fire-rated glass also be impact-rated and bullet resistant?>
When designing safe schools or enhancing building security, it is important to note no material or system can accurately be called “bulletproof.” In part, this is because the type of firearm, caliber and ammunition, as well as shooting range and shot patterns, can vary significantly between active shooter events. As a result, systems are tested to industry standards, such as UL Solutions standard (UL) 752, to determine the level of bullet-resistance they provide.
The 11th edition of UL 752 categorized assemblies across eight levels according to different data points such as caliber of bullet and shot pattern. Its 12th edition uses a different system, one that offers more clarity on what a specific rating means.
For the 11th edition of UL 752, levels one through three addressed pistols while four and above tested materials against rifles and shotguns. However, some materials that passed level three could also pass level six but not levels four and five due to the ammunition used and how it interacts with a target. Exceptions like this were confusing for professionals working on school building design and other projects aiming to enhance security. They also led to an overhaul of the standard.
The 12th edition of UL 752 uses performance designations to clarify what types of threats bullet-resistance glazing can withstand. For handguns (UL-HG-), there are four designations, A through D. For rifles (UL-RF-), there are ten, A through J. And for shotguns (UL-SG-), there are two, A and B. Similar to the 11th edition, each designation provides different testing data to be used by security professionals and specifiers when assessing which level of protection is most appropriate for a given application.
Neither the 11th nor 12th editions of UL 752 progress linearly, where one level adds a degree of resistance to the level directly before it. Instead, each level offers data related to weapon, ammunition and shot pattern used in the test. For this reason, it is important to conduct a security risk assessment when a school building design seeks to enhance security. Doing so not only provides vital information on which locations may be most essential for a baseline in designing safer schools, but it also offers more insight into which security ratings are most appropriate.
These assessments take into account other security measures in place or included in a design, statistical likelihood of various weapons, police response times and other data to provide recommendations to achieve a school’s security goals.
While a security professional may recommend the use of bullet-resistant glass, they may also recommend forced-entry rated systems, which withstand blunt force attacks for a designated amount of time after being shot according protocols in the ASTM International standard ASTM F3561. Although forced-entry rated systems do not defend against ballistic attack, they remain intact to provide a time barrier between a violent intruder and occupants. ASTM F3561 and UL 752 are complementary standards that address different aspects of fenestration system security to create a more comprehensive approach to safer school building design.
While enhancing security from the property perimeter to the classroom door can be an important step to giving comfort and peace of mind to parents, faculty, students and staff, it is not the only aspect of school building design. Fire and life safety also play a large role in safer school design—especially considering there are over 3,000 fires on school campuses annually.
Given that many security-rated components are plastic-based and so burn quickly and intensely, they may exceed parameters typical in a building fire—ones that are closely modeled during the fire test. As such, they may inhibit or negate a fire-rated components rating, potentially putting occupants at risk. In instances where security goals and code requirements for fire and life safety overlap, it is important that a full system can meet multiple testing standards to ensure one form of defense is not sacrificed for another.
Explore how multifunctional, fire-rated systems from Technical Glass Products (TGP) can support many aspects of safer school design.
