A wildfire burns in the hills of a Los Angeles suburb, leaping from one patch of dry brush to another as it approaches a cluster of homes. The landscaping at the first house burns, but the house itself stubbornly refuses to catch fire: any small flames that start along its walls or roof quickly die out. There’s no water in sight—the flames are being quenched by sound waves. This kind of acoustic fire suppression may soon play a vital role in fighting wildfires.
The key ingredients for a fire are heat, fuel and oxygen; take one of these away, and the flames are extinguished. Sound waves can stifle a fire by pushing oxygen molecules away from the fuel, preventing the fire from getting the air it needs to continue its combustion reaction.
Geoff Bruder, an aerospace engineer who researched thermal energy conversion at NASA, co-founded Sonic Fire Tech to build a sound-generating machine for this purpose. “It’s basically vibrating the oxygen faster than the fuel can use it, so you block the chemical reaction,” Bruder says. The company has demonstrated fire suppression from up to 25 feet away.
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
Using sound waves to fight fire isn’t a brand-new concept. The U.S. Defense Advanced Research Projects Agency studied the method from 2008 to 2011, and academic researchers explored the technique over the next decade (including a George Mason University team that built an extinguisher similar to a subwoofer in 2015).
“Acoustic influence on flames is well known in combustion,” says Albert Simeoni, head of the department of fire protection engineering at Worcester Polytechnic Institute in Massachusetts. “The challenge is to scale up the technology without creating disrupting or even damaging sound effects.”
Sonic solves this challenge by using infrasound. Whereas previous efforts used sound waves in the range of 30 to 60 hertz, which can be produced with simpler equipment, Sonic stays at or below 20 hertz. These waves are inaudible to people, and they travel farther than higher-frequency waves.
Homes often catch fire from embers accumulating in adjacent foliage or entering attic vents, Bruder says. Sonic’s system uses a piston pulsed by an electric motor to create sound waves, which travel through metallic ducts installed on a building’s roof and under its eaves. The system autoactivates when sensors detect a flame, creating a kind of force field of infrasound to extinguish it and prevent new ignition.
Acoustic waves can have a strong effect on fire, but they work only on small flames, says Arnaud Trouvé, chair of the University of Maryland’s department of fire protection engineering. Nevertheless, homeowners and utilities are game to give it a try: Sonic is working with two California utilities to demonstrate its technology. Homeowners have also signed contracts with the company, which is aiming to have 50 pilot installations early in 2026.