Original Source: The Atlantic, Author Brian Mockenhaupt May 23, 2014
http://www.theatlantic.com/technology/archive/2014/05/fire-shelters/371421/
When a blaze takes an unexpected turn, a thin aluminum shelter is a firefighter's last resort.
(During the Little Venus Fire, a firefighter reached out of his shelter to photograph the burning forest. (Courtesy of the Little Venus Fire Shelter Peer Review Report)
In my feature story in the June issue of The Atlantic, I wrote about a wildfire in Yarnell, Arizona, that trapped 19 firefighters last summer. As the blaze changed direction with unexpected ferocity, they had one chance for survival: lie face down on the ground, cover themselves with a thin aluminum shelter, and let the fire burn over them. Some made it into their shelters, but it didn't matter; the speed and intensity of the fire was too much.
But fire shelters have saved hundreds of people’s lives, and saved hundreds of others from serious burns. I wanted to get a sense of what it’s like to endure a burnover, so I spoke to Lathan Johnson, a Colorado firefighter who survived a shelter deployment on the Little Venus Fire, which burned deep in the backcountry of Wyoming's Shoshone National Forest in July 2006.
“You're not always going to be able to outsmart a fire,” Johnson said. “I thought for sure I'd never have to use a fire shelter, and then I find myself shaking out one, pretty thankful that I had it.”
Johnson was overseeing a small group assigned to relieve another crew that was monitoring the fire several miles up a river valley. They got a late start and didn't hike up the river valley until the afternoon, the most dangerous time for a wildfire, when the sun is hot, relative humidity is low, and the winds are high. “That's when bad things happen on a fire,” Johnson says. “We call it the witching hour.” Indeed, the Wildfire Lessons Learned Center in Tucson, Arizona, studied 115 instances of firefighters trapped by wildfire over the past 20 years and found that half occurred between 2 p.m. and 5 p.m., and all but 12 happened between noon and 6 p.m.
Johnson also knew a weather front would pass through sometime in the afternoon, which usually meant a shift in wind direction. But spotty radio communication deep in the valley kept him from grasping the change in fire activity until he turned a corner on the trail and saw a massive black smoke plume several hundred yards up the canyon. The fire was coming for him and his crew, tearing through stands of bug-killed trees, which spread the fire even faster.
Johnson did a quick headcount and came up one short. He didn't know that one of his firefighters had panicked and split off from the group a few minutes earlier. They didn't have time to look for her: they couldn't outrun the fire, and if they waited any longer to deploy, they might not have enough time to get under their shelters before the wall of flame washed over them. Between them and the fire was a 30-foot rock face, which would give some shelter from the heat and flame.
“We're going to deploy here,” Johnson told the crew. For a moment, he saw their fear and disbelief. But then they set to work, reverting to procedures that they knew well from annual training exercises. The familiar routine seemed to calm them, offering the illusion of control: Unzip the carrying case, pull out the shelter, and shake it open. Step into it, pull it over your head, and lie down with your face close to the ground, where the air is cleanest and coolest. Use your elbows, knees, and feet to pin the shelter down against winds created by the fire that might top 60 mph.
A minute or so after Johnson worked himself into his shelter, the first wave of heat and flame and noise swept over him. It lasted about five minutes. The shelters did their jobs well, deflecting most of the fire's radiant heat. He and the others left their shelters to put out some spot fires and to burn other areas of brush to better protect themselves. Another wave of fire was coming, and they knew it would last much longer. They covered themselves once more. Embers and chunks of debris rained down on Johnson's shelter. From inside, he tried to knock them off while constantly shifting his weight to keep his shelter edges pinned down. He heard nearby trees burst into flame with a whoosh. He tried to peek out of the shelter, and smoke and hot air poured in. He thought about his year-old son, but mostly he thought about his missing crew member. How would he explain to her parents that he had let their daughter die?
The firefighters had packed close together, which reduced their overall exposure to heat and put them near enough to talk to one another over the roar of the fire. They tried to calm a frantic crew member who wanted to run, which has happened, several times—convinced he'll burn to death, a firefighter in a shelter figures he would be better off trying to outrun the flames, or just getting the inevitable over with more quickly. During the 1990 Dude Fire near Payson, Arizona, during a burnover that lasted 15 minutes, firefighter Curtis Springfield called out to his colleagues, “I can't take it anymore.” He then broke out of his shelter, sucked hot air into his lungs, and died. The Dude Fire killed five other firefighters who left their shelters or hadn’t fully deployed them. Four firefighters who stayed under their shelters during the burnover survived, most with minor burns.
During the Little Venus Fire, after the flames passed through Johnson's deployment site along the creek, the heat ebbed and the smoke cleared. Forty-five minutes after the second wave of fire hit them, the nine firefighters emerged from the shelters to find one another relatively unscathed, with only a few minor burns. The tenth firefighter had deployed her shelter in a rocky streambed, and although she had faced a more intense wall of flame, she, too, was unhurt.
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