The 19 firefighters killed in the Yarnell Hill Fire southwest of Prescott were part of an elite firefighting crew called the Granite Mountain Hotshots.
According to the Arizona Incident Management Team, the crew deployed its "fire shelters" -- which a federal government manual describes as a "last resort" for wildland firefighters.
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"The fire shelter has been required equipment for wildland firefighters since 1977," the manual on the "New Generation Fire Shelter" says. "Since that time, shelters have saved the lives of more than 300 firefighters and have prevented hundreds of serious injuries. A new generation of fire shelter now offers improved protection from both radiant and convective heat. Even so, the shelter will not protect firefighters under all fire situations."
It's possible that some of the firefighters may not have utilized their shelters properly, as they are tricky to use. Even if they all used it properly -- which will be investigated -- it's still entirely possible that it was just too hot to survive.
The bag reflects radiant heat, while trapping air, allowing a person inside the bag to breathe.
However, when flames and hot air come into contact with the material, it starts to heat up.
"When the material reaches about 500 degrees Fahrenheit, the glue that bonds the layers begins to break down," the manual says. "The layers can separate, allowing the foil to be torn by turbulent winds. Without the foil, the shelter loses much of its ability to reflect radiant heat."
It's pretty chilling now, but last year, ASU student reporters were with the Prescott-based Granite Mountain crew, doing a story on them as they practiced using these fire shelters.
"The day included watching a video on how to use emergency shelters and what conditions crew members might face if overrun by fire," the accompanying print report says. "The video featured survivors of the 1990 Dude Fire near Payson, in which six firefighters died despite wrapping themselves in shelters."
The government manual on the shelters, printed in 2003 by the National Wildfire Coordinating Group, includes quotations from accounts of firefighters who have survived fires in the shelter, and it gives you an idea of what these guys may have been thinking while trying to protect themselves from the flames:
We need to emphasize that to people, that they may receive injuries, but their greatest hope is staying inside that shelter and protecting themselves, no matter what they hear, no matter what they see or feel, that they have to make just an absolute commitment to staying with that shelter if they want to go home.
This was like a nuclear blast occurring right over you and you're lying in tinfoil.
It was extremely painful. Things that were going through my head were, "I'm going to die; this is going to kill me." Afterwards, I remember thinking that because my legs were burned on the back of both calves and the backs of my thighs and it was so painful and it had gone on for such a long period of time that they were probably going to have to amputate my legs. You believe that you're being burned to death or that you're being burned to the point that you'd never be able to use those limbs again. . .
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