UL 972 Testing for Burglary-Resistant Glazing Materials

Underwriters Laboratory test standard UL 972 considers the ability of a laminated glass to resist burglary or
forced entry. The test consists of dropping a 3.25-inch, 5-lb. (2.25-kg) steel ball through a designated vertical distance onto a sample measuring 24 in. by 24 in. (61 cm by 61cm). Vertical (drop) distance controls impact energy, and the temperature conditions are controlled to consider indoor versus outdoor glazing applications. Test requirements for a UL 972 listing are shown below: