While it isn’t possible to completely prevent explosions, there are ways to minimize, or “mitigate,” the amount of damage done to the building and those inside of it. These bomb blast mitigation techniques can include incorporating blast resistance into building design and installing blast-resistant doors and windows are collectively called “blast mitigation glass”.
It often isn’t the explosion itself that harms glass, but the pressure wave that follows. This pressure wave causes glass windows to shatter often just from the sheer force and sometimes from the debris that it carries with it through the air.
Regular glass shatters into dangerous shards called spall which can then be carried through the air at high speeds. That flying glass can easily injure people and damage assets. A large portion of injuries from blast-related incidents is caused by glass fragmentation, glass breakage, and spall, which is why the main focus of blast mitigation is impact protection, which reduces the risks of injuries from flying projectiles.
There are several blast-resistant window products out there, but some of the best-performing options are made of polycarbonate, like DefenseLite. With strength 250 times that of glass, DefenseLite’s proprietary polycarbonate blast-resistant barriers for doors and windows stand up to the blast wave and flying objects without shattering, eliminating the threat of broken glass.
Additionally, bomb blast-resistant windows can be made of laminated glass. While these windows won’t stand up to a bomb blast the same way polycarbonate panels do, laminated glass won’t shatter into dangerous shards as regular glass does. A layer of plastic between the glass keeps this type of window from flying inward when shattered, offering an added layer of blast resistance over the plain glass. However, laminated glass tends to negatively impact visibility, whereas polycarbonate does not.
“Blast mitigation windows” is another term used to describe windows that are built to withstand the pressure wave from an explosion. Since these reinforced windows can mitigate the damage caused by a bomb blast and resulting pressure wave, they are often referred to as “blast mitigation windows.”
Just like “blast-resistant windows”, these windows can be made of laminated glass or polycarbonate.
Blast resistance is the ability of a material or structure to withstand pressure from an explosion. Since “blast-proof” would mean that the material is entirely immune to damage from an explosion (one example would be concrete), it’s not a term commonly used when discussing windows and doors. Instead, we use the term “blast-resistant.”
There are varying levels of blast resistance, so make sure you know how blast-resistant your windows are. You can learn more about DefenseLite’s blast resistance standards here.