A firefighter’s outerwear is exceptionally important; its quality and material keep the wearer safe. But the same attention hasn’t been given to what a firefighter wears as underwear. That’s a big problem, especially for women, because most sports bras are made of material that can melt and burn in high heat — even if the outerwear is not damaged. The World’s Marco Werman speaks with Emily Pyke, an Australian Navy veteran and founder of UndaTech, which is developing fire-resistant bras and menstrual briefs.