75% of secondary fragmentation injuries come from which material?

• A. Metal
• B. Wood
• C. Concrete
• D. Glass

Answer: (D)

In blast injuries, secondary fragmentation injuries come from objects in the environment that become propelled as the blast disrupts them. Glass from windows is the predominant source because buildings are full of windows, and glass is brittle enough to shatter into a large number of sharp, high-velocity fragments when exposed to the blast. Those shards can penetrate skin and deeper tissues readily and can travel significant distances, making glass shards the most common cause of secondary injuries. While metal, wood, and concrete can also fragment and cause harm, their contribution is typically smaller than that of glass in most settings. This is why protecting windows or using blast-resistant glazing helps reduce these injuries.