After an Arizona fire claimed the lives of 19 expert "hotshot" firefighters, Pennsylvania fire officials are asking why this wildfire quickly became one of the deadliest.
"It's shock at first," said Brian Vinski, a fire specialist supervisor for the Pennsylvania Bureau of Forestry. "You just immediately go to 'Why? What went wrong?' "
Mr. Vinski, a graduate of North Allegheny High School who has fought wildfires from California to Florida, said the first few days of a major wildfire in the western United States are often the most volatile.
Logistical support and coordination efforts are in their early stages and fire personnel -- who can number into the hundreds -- are often just beginning to assess the blaze.
Fire officials were reluctant to speculate on what may have contributed to the nation's largest loss of firefighters to a wildfire in 80 years, but one thing is clear: Despite rigorous safety training and advances in technology, trying to control large-scale wildfires continues to be dangerous.
"The risk is always there," Mr. Vinski said. "So many of these fatalities and burnovers occur in the initial attack stages. As an incident grows, you get that formal structure that manages all those resources with a lot more control."
Mike Kern, wildfire operations chief for the Pennsylvania Bureau of Forestry, also expressed surprise at the loss of life in Arizona.
"There's been a real push to not put people in dangerous conditions," he said. "The scale of the tragedy was really surprising. I just really didn't think anything like that would happen."
An Arizona state forestry division spokesman said all 19 firefighters deployed their fire shelters, which are essentially small tents that can protect against intense heat and smoke.
But they are only used in dire circumstances.
"They can't survive direct contact with flames for very long," Mr. Kern said. "If you have to use a fire shelter, then something went wrong."
Unlike building fires, where flames can be directly and quickly extinguished, the strategy for managing wildfires typically requires firefighters to travel through remote areas and begin digging trenches in the hope of successfully containing fires that can span thousands of acres.
"The main tactic with wildfires is basically to clear the fuel out in front of the fire," Mr. Kern said.
In Pennsylvania, the vast majority of wildfires are caused by people and are extinguished in a matter of hours.
But when crews respond to fires in remote areas, it can take an entire season before the fire is completely under control.
"There are fires out West that they don't ever stop from spreading," Mr. Kern said. "The winter just puts them out."
Alex Zimmerman: 412-263-3909. The Associated Press contributed.