California startup's new fire-suppression system uses sound instead of water

Forward-looking: When wildfires sweep through the dry hills outside Los Angeles, homes can be lost in moments. A California startup imagines a different outcome: as embers fall and nearby brush ignites, flames reach a house and abruptly die out. There's no water, foam, or retardant involved – only inaudible waves of sound extinguishing the fire before it spreads.

Sonic Fire Tech, co-founded by aerospace engineer Geoff Bruder, has developed a system that uses infrasound – low-frequency sound waves below the threshold of human hearing – to suppress fire.

Bruder, who previously researched thermal energy conversion at NASA, says the key is shaking up the oxygen molecules that feed combustion. When vibrations disrupt how oxygen mixes with fuel, the chain reaction that sustains a flame collapses.

The principle behind acoustic fire suppression isn't new. From 2008 to 2011, the US Defense Advanced Research Projects Agency studied the possibility of using sound to manage flames, and university researchers later built experimental versions, including a device from George Mason University that operated much like a subwoofer.

What sets Sonic Fire Tech apart is its use of infrasound. Earlier designs operated at 30 to 60 hertz, producing audible tones that could interfere with nearby structures or people. Sonic's system works at 20 hertz and below – frequencies not only inaudible but capable of traveling greater distances without distortion.

According to Bruder, Sonic's system works through a piston-based generator powered by an electric motor. The piston emits pulsed sound waves through metal ducts mounted under a building's roof and eaves. Arrays of sensors detect heat or flame and automatically trigger the system.

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