For almost 50 years, fire extinguisher technology has remained virtually unchanged: You muffle the fire with a blanket, or spray it with a sprinkler system or pressurized canister. Today, DARPA shows off a new breakthrough: Extinguishing a flame using sound.

In 2008, DARPA — the US government’s military research wing — launched the Instant Fire Suppression (IFS) research program, tasked first with finding out more about the actual nature of fire, and then using this new-found knowledge to develop novel fire suppression techniques. Basically, while almost every existing fire extinguisher tries to interrupt the chemical reaction (smothering the fire with carbon dioxide, for example), DARPA’s main realization was that flames are cold plasmas, and thus could be manipulated with physical forces such as electromagnetic radiation and acoustic waves.

At the beginning of the year, DARPA demoed small-scale electromagnetic fire suppression (video at the end of the story), and now — as you can see below — the agency has created an acoustic wave fire extinguisher. I suggest you turn your sound down before you click play.

There are two forces in action here: 1) The acoustic waves increase the velocity of the air, thinning the boundary layer where combustion occurs; and 2) The waves disrupt the surface of the fuel, which increases the width of the flame, disrupting combustion as the same amount of heat is spread over a wider area. Curiously, Mythbusters actually demonstrated and explained this same effect back in episode 76, which aired in 2007 — a full year before launching the IFS program. It’s possible that President Obama, who has appeared on Mythbusters, gave DARPA a recording of the show and told them to look into it.

As for the purpose of electromagnetic and acoustic fire extinguishers, it’s all about putting out fires that occur in enclosed spaces, such as airplane and vehicle cockpits, and below deck on ships. Imagine if a super-powerful tannoy system was all you needed to put out a fire anywhere on an aircraft carrier — and indeed, the IFS project was started because of a fire aboard USS George Washington in 2008 that caused $70 million of damage.

It’s fairly safe to assume that this new fire suppression tech will find its way into the hands of businesses and consumers, too. I mean, DARPA is fairly good at sharing; it did invent the internet and then invite everyone to come and play, after all. Maybe this is finally the justification that I need to invest in a pair of 1000-watt speakers for my house, hmm…

Read more at DARPA