Glass Ballistic Tests: An Overview

When it comes to protecting people and property against threats that can result in damage, theft, and physical harm, there’s no better solution than ballistic glass, or bullet-resistant glass.

Depending on their specific composition, different types of ballistic-grade security glazing provide varying levels of bullet resistance against specific types of ammunition and firearms.

In order to be officially certified and sanctioned for use in bullet-resistant windows and doors, ballistic glass must be rigorously tested according to one or more of the official glass ballistic testing standards available.

Understanding Glass Ballistic Tests

The tests help manufacturers and researchers design and improve glass-based and glass-like protective barriers to enhance the safety and security of individuals and assets, primarily in high-security commercial, government, and military settings.

Key Characteristics Tested

• Bullet Resistance: Determines the glass's ability to impede bullets of varying calibers and velocities, dictating its ballistic resistance rating.
• Fragmentation Resistance: Assesses resistance against explosive fragments or shrapnel, vital for protection against blast impacts.
• Multi-Hit Capability: Evaluates if the glass maintains protective properties after sustaining multiple impacts, crucial for sustained defense.
• Transparency: Considers optical clarity and resistance to spalling, ensuring functionality without compromising visibility.
• Environmental Conditions: Examines performance under diverse environmental factors like temperature extremes or moisture exposure, ensuring reliability in various conditions.

Types of Ballistic Tests

Different global organizations establish standards for consistent and reliable testing procedures. In the United States, the Underwriters Laboratories (UL) 752 standard is prominent, offering a comprehensive framework for testing and classifying bullet-resistant materials.

UL 752 Standard Overview

UL 752 provides clear testing procedures and performance criteria, classifying materials into different protection levels based on their ability to withstand ballistic threats of varying magnitudes. For instance:

Level 1: Protects against 9mm FMJ bullets.

Level 2: Provides defense against higher velocity 9mm FMJ bullets.

Level 3: Offers protection against .44 Magnum LSW bullets, and so forth.

The testing involves shooting specimens with specified projectiles at defined velocities and distances, assessing their resistance to penetration and deformation.

Consideration of Other Standards

While UL 752 is prominent, various regions and industries may adhere to alternative standards like the National Institute of Justice (NIJ) or European Standards (EN). Selection of bullet-resistant materials should align with relevant standards pertinent to the application's requirements and regulations.

What About Bulletproof Glass Testing?

You may have noticed that we have only discussed testing for bullet-resistant glass, and haven’t mentioned bulletproof glass testing. This is because the term “bulletproof” glass is really just a marketing term used to refer to different types of ballistic glazing.

In reality, any type of ballistic grade glazing can eventually be penetrated, either by a more powerful type of firearm/ammunition or by a high enough volume of shots.

This is why glass ballistic tests are so important — they specify exactly what level of ballistic protection you can expect from any given piece of ballistic-grade security glazing.

At Riot Glass, LLC we offer a full range of forced entry and bullet-resistant glazing products. Contact us today to discuss how we can harden your commercial property’s security with a security glazing retrofit.