Fires are unpredictable—a matter of seconds can mean the difference between minor burns and life‑threatening injuries. Fire‑resistant clothing can buy those critical seconds that save lives.

There are two different standards in the clothing industry, for two different levels of protection against thermal burns:

• Fire retardant stands for chemically treated natural fibers (such as cotton) that can temporarilly slow flames. However, the treatment can wash out over time, reducing protection.
• Fire‑resistant clothing, developed in the 1960’s, is made from inherently fire-resistant fibers. These materials have heat‑resistant properties built into their chemical structure. They don’t melt or burn easily, and when exposed to flames, they self‑extinguish the fire.

Alice Mary Stoll, a researcher at the U.S. Naval Air Development Center, led work that was fundamental in shifting protective clothing from relying on fire retardant materials to using structurally safe, inherently fire‑resistant fibers. She redefined standards in safety apparel—pioneering a transition that endures today in high‑risk industries. In 2024, she was inducted into the National Inventors Hall of Fame.

Stoll developed rigorous testing methods to assess fabrics’ thermal protection, including her seminal “Stoll curves,” which relate heat exposure to burn risk. Using her new methods, she tested over 200 fabric types. Through her systematic and careful efforts, she identified HT‑1 (which is a type of polymer known as an aramid polymer), as the standout performer when it came to heat resistance. This material has the exceptional ability to thicken and carbonize under extreme heat, preventing melting and significantly improving thermal protection.

HT‑1 was later released commercially by DuPont as Nomex® in 1967—ushering in a new generation of truly fire‑resistant materials. It became the heavyweight standard in protective gear, and is used in firefighter suits, military flight suits, race‑car driver uniforms, and astronaut apparel. Stoll’s federally funded research has protected the lives of countless first responders, as well as many others.