Dangers of Improper Wear: Episode 2 – Base Layers Should Not Melt!

Our Dangers of Improper Wear series examines many of the common mistakes people make when wearing arc-rated and flame resistant (AR / FR) clothing, with real-world arc flash video footage that shows just how substantial each mistake can be. In each episode, you’ll find powerful examples of why wearing the right PPE, and wearing it properly, makes all the difference – with expert commentary from Scott Margolin, Vice President of Technical.
Streetwear base layers are usually constructed from popular, man-made fabrics such as nylon, polypropylene, or spandex. When wearing these fabrics underneath arc-rated and flame resistant (AR / FR) clothing, you are at risk of serious injury, and we’re going to tell – and show –you why. When exposed to the extreme temperatures of an arc flash, these types of fabrics melt and can severely burn the skin, even if they’re worn under clothing with an arc-rated greater than the arc you might be exposed to.
To prove that meltable base layers don’t hold up even when layered under AR clothing, we put meltable base layers to the ultimate test by conducting live arc-flashes at an independent laboratory in Chalfont, PA. Watch our live arc-flash demonstration to see why industry standards say that base layers cannot be meltable and listen along as VP of Technical, Scott Margolin, explains the consequences of wearing improper base layers.
The fact is, meltable base layers are not compliant and they aren’t compliant because they’re not safe. Liquids are much more efficient than air at transferring heat. So, once a meltable base layer melts, the wearer is left with molten polymer burned to his or her skin.
As seen in the video, Tyndale conducts an arc of 8.3 cal/cm2 on a manikin wearing an arc-rated 8.6 cal/cm2 shirt. Since the shirt’s arc rating is greater than the arc conducted, in theory, there should be no injury. However, the arc-flash produces a fire, igniting the non-AR base layer under the AR garment, which spreads, melts the base layer, and causes massive damage.
To further prove why wearing improper base layers is so dangerous, here’s a second video of an arc, demonstrating the consequences of wearing meltable base layers.
Again, we conducted this arc at a rating below the arc rating of the outer layer, which, in theory, means that the base layer shouldn’t be affected. However, even though the arc-rated shirt did its job, meaning it didn’t break open or catch on fire, the meltable base layer shrinks and completely melts, putting the potential wearer at serious risk of injury.
The bottom line? Meltable base layers undermine the protection that your AR outer layer provides.