Spreading Like Wildfire? Maybe Not Always

One of America's most costly natural disasters are wildland fires, and wildland-urban interface (WUI) fires rank among the worst of these. WUI is the threshold where wildfires consume not only the landscape, but also infrastructure. Once that threshold is crossed, flames can spread -- well, like wildfire. In quick succession, when a racing fire crosses the WUI, houses first smolder, then burn, and finally fall like wooden dominoes. And it can happen very quickly, as we all know. Half of all billion-dollar blazes are WUI fires, which can ignite as many as a dozen homes a minute. This type of fire is both a wall of flames and a wave of firebrands. Lofting onto shingles or floating into eaves, the firebrands smolder before setting their resting place ablaze. More intrusive firebrands drift through gable vents or down chimneys, torching the house from within and creating new firebrands.

Since 2008, the Department of Homeland Security (DHS)'s Science and Technology Directorate (S&T) has been funding experimental WUI fire research at the National Institute of Standards and Technology (NIST) to discover when, how, and how often embers start fires after they land.

"WUI fires rank among America's most costly catastrophes," says S&T Office of Standards Executive Bert Coursey. "These studies aren't about blowing smoke; they're science at its best."