The 2020 update to ISO 16932, “Glass in Building — Destructive-Windstorm-Resistant Security Glazing — Test and Classification,” includes missile size changes for Levels 3 and 4.

According to Julia Schimmelpenningh, Customer Applications and Support Lab manager for Eastman Chemical Co., the missile size for >10 meters in Level 3 and Level 4 have been elevated to larger missiles than the ball bearings.

Level 3 saw the biggest change in that instead of requiring only the small ball bearings it’s now required to face an impact with a 1 kg small timber when the fenestration is higher than 10 meters. A significant difference between ISO 16932:2020 and ASTM E 1996 is that Level 4 protection requires that the large 4 kg timber at 15 meters per second be used even when the fenestration is above 10 meters. ASTM requires only small missile for these applications. Despite the difference, the test methodology, pass/fail criteria and building height delineations remain the same. A diagram also was included in the standard to show the order of the impacts.

Level 3 is advised for buildings expected to have a substantial hazard to human life in severe storms. This includes offices, schools, hotels and major shopping areas. Level 4 is advised for enhanced protection of essential facilities such as hospitals, emergency service buildings and storm shelters.

The updated standard document may be purchased here.