Despite the most scrupulous planning, wildland firefighters can suddenly find themselves encircled by unpredictable flames reaching nearly 1,500 degrees Fahrenheit. Unable to escape, they have no choice but to hunker down inside fire shelters—reflective, foil-like mini tents—and hope the flames pass over them quickly.
In the summer of 2013, 19 firefighters deployed their standard-issue shelters in Yarnell Hill, Ariz.—but the conflagration proved too much, and none of them survived. After learning of the tragedy, scientists at the NASA Langley Research Center set out to build a better shelter. They used inflatable heat-shield technology designed to withstand the scorching temperatures that spacecraft endure when passing through Earth's atmosphere (2,000 to 5,000 degrees F). In mid-April the U.S. Forest Service blasted the NASA shelters with flames at a research facility at the University of Alberta. Results have not yet been released, but earlier tests were promising. If this space technology proves sturdy enough, firefighters may carry it into the woods this summer.
Traditional fire tents have saved hundreds of lives in the past half-century. But the Yarnell Hill incident showed that “the shelters could not withstand significant, direct-flame heating,” explains NASA thermal scientist Josh Fody, who helped to develop the prototype. The heat-shield material can do so, however. Embedded in the thin fabric are bits of graphite the size and shape of pepper flakes. When exposed to flames, the graphite causes a layer of fiberglass insulation to expand, creating “a big, fluffy blanket,” Fody says. He calls the material “smart” because it expands only when exposed to high temperatures. Its lightweight design is crucial because wildland firefighters often trek through tough terrain and cannot lug cumbersome gear.
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
If proved, this technology could not come at a better time. Wildfires now burn twice as much land in the U.S. as they did 20 years ago because of a hotter, drier climate, says Forest Service ecologist W. Matt Jolly. “This means firefighters are exposed to more fire than ever before.”