Tech Tuesday: Extinguishing fire with sound

Sam Vander Forest

Sorry for the delay, but who doesn’t love Tech Tuesday on a Friday? This story is too interesting to ignore, no matter how late the segment is.

Two senior engineering students at George Mason University have invented a somewhat portable device that uses low frequency sound waves to extinguish small fires, and it’s absolutely incredible.

The Defense Advanced Research Projects Agency (DARPA) first researched the idea in 2012, but no further innovations have been made and no defense-worthy application was found. However, GMU seniors Seth Robertson and Viet Tran saw the possible application in preventing small stovetop fires, small house fires and possibly forest fires one day.

The device consists of a sound generator, amplifier, power source and focusing tube, and although it is bulky and rough looking now, it is still less hazardous and messy than traditional fire extinguishers. The device works by creating low frequency sound waves that work as pressure waves to displace the oxygen in the fire. When at a certain frequency, the waves can separate the oxygen from the fuel in the fire, which then creates enough of a gap to keep the fire from reigniting.

While their testing and device are in early stages and can only put out alcohol-based fires, the duo envisions much greater applications later on. Fire extinguishers contain ammonium phosphate or ammonium sulfate and are tricky to clean up, so being able to eliminate the hazardous chemicals and cleanup costs would provide tremendous savings. On top of that, if the technology is eventually able to put out large-scale fires, then the amount of lives it could save would be immeasurable.

The two electrical engineers have a ways to go still, but furthering DARPA’s research and making it accessible to the public is a great thing. Will this device be installed above stovetops or available in household kitchens in the next 20 years? It’s tough to say, but I wouldn’t doubt it. Look for these two names to pop up more in the near future, but until then you can check out their demonstration video below.