Fiery tests can assess new prototypes of portable shelters, the last line of defense for wildland...
The National Wildfire Coordinating Group, a federal government organization that sets standards for wildland fire equipment, reports that fire shelters have been deployed more than 200 times between 2006 and 2020.
19 of the 20 members of the Granite Mountain firefighting crew tragically perished despite using their shelters in Arizona's 2013 Yarnell Hill Fire.
The need for better shelters will only become more crucial as fire seasons continue to grow more severe: last year alone, firefighters battled almost 60,000 wildfires that turned seven million acres of U.S. forest into blackened ash.
"The fire seasons are lengthening, getting more severe, and wildland firefighters are seeing fire behavior that we haven't seen before," says Camille Stevens-Rumann, an assistant professor of forest and rangeland stewardship at Colorado State University, who was not involved in the recent fire shelter tests.
"In Colorado, we had a fire that burned 6,000 acres an hour. Those conditions lead to more risk for firefighters." Such situations are particularly dangerous when flames spread quickly in a short period of time, forcing firefighters to retreat to their emergency shelters.
Within the chamber, propane burners blasted full-size fire shelters with a direct flame for one minute.
Fire shelters must withstand two types of heat.
Because real wildfires create such unpredictable conditions, it is necessary to test fire shelters in the field, as well as in the laboratory.
"There are a lot of variables in a wildfire environment. It's very unpredictable. You could have a shelter next to another shelter, and when fire runs through the area, you've got surprisingly different results between the two," says David Maclay-Schulte, an equipment specialist at the U.S. Forest Service's National Technology and Development Program, who did not work on the new N.C. State report.
When exposed to high heat these substances release toxic fumes that would endanger firefighters using the shelters.