EVs and the DC Hazard: Cotton Workwear in a DC Arc

With the rapid growth of electric vehicles (EVs), and the infrastructure needed to support them, so too grows the importance of understanding the direct current (DC) arc hazard. That’s where Tyndale comes in! This series lays out the differences between the alternating current (AC) arc hazard and its lesser-known DC counterpart and demonstrates – through first-of-its-kind real-world video footage – the power of DC arcs. Follow along to learn more and witness firsthand the life-saving difference the right arc-rated (AR) clothing makes in the face of a DC arc.
Many people think that 100% cotton is okay to wear when there’s an arc hazard because it doesn’t melt. But is that true? Can a DC arc flash ignite flammable 100% cotton workwear, and does it require any more or less energy than an AC arc to do so? Plug in to this leading-edge DC arc demonstration video to find out:
The standards are clear, and the proof is in the footage – 100% cotton workwear is NOT safe to wear when there’s a risk of arc flash in your work environment:
- It’s not allowed by the standards like NFPA 70E, and not acceptable by OSHA
- It’s not safe in an arc flash, as you can see in the video above
As our host Scott Margolin, Vice President of Technical, explains, there are four main hazards associated with wearing 100% cotton fabric in the event of an arc:
- It ignites easily
- When burning, it reaches higher temperatures than other fabrics
- It’s harder to extinguish – our crews experienced this firsthand during our demonstration
- It’s heavy in weight – meaning more fuel for the fire
As a result of all of these factors, the manikin in this demonstration sustained 60%+ body burn at an incident energy of 7.3 calories.
This video shows why it’s so important to wear arc-rated (AR) clothing and appropriate PPE when there is an arc hazard in your job environment. In fact, in most of the injuries and fatalities we see, the outcomes were preventable – caused by people wearing fuel. This video shows that the DC arc hazard is no exception. Don’t leave home without your last line of defense.
How do popular AR garments perform in DC arcs at or near their arc ratings? Follow along with our next few episodes to find out. First up, we put an NSA TECGEN® coverall to the test in a DC arc.