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27 A new firefighter

You need a lot of water to put out a sizable blaze, and the chemicals used in fire extinguishers can be toxic (halons, the most effective chemical fire suppressant, create holes in the ozone layer). So the Defense Advanced Research Projects Agency at the Pentagon has developed a hand-held wand that snuffs out fires, without chemicals. According to the program’s manager, Dr. Matt Goodman, an electric field destabilizes the flame’s underlying structure rather than blanketing the fire to smother it. Eventually, the technology could be used to create escape routes or extinguish fires without damaging sensitive equipment nearby. Nathaniel Penn

文章網址

http://www.nytimes.com/interactive/2012/06/03/magazine/innovations-issue.html