In a makeshift demonstration kitchen in Concord, California, cooking oil splatters in and around a frying pan, which catches fire on an unattended gas stove. Within moments, a smoke detector wails. But in this demonstration, something less common happens: An AI-driven sensor activates and wall emitters blast infrasound waves toward the source of the fire in an attempt to put it out.
The science of acoustic fire suppression, which has long been known and documented in scientific literature and the press, works by vibrating oxygen molecules away from a fuel source, depriving the fire of a critical component needed for combustion. Indeed, after just a few seconds of infrasound, the tiny kitchen blaze goes out.
The demonstration I witnessed took place in the presence of numerous firefighters and officials from Contra Costa County Fire Protection District, CAL FIRE, and invited journalists.
“We were able to not just point-and-shoot like a fire extinguisher; we figured out how to run it through ducting and distribute it like a sprinkler system,” said Geoff Bruder, co-founder and CEO of Sonic Fire Tech, during the presentation. The company’s goal is to replace sprinklers, which are effective at stopping fires but can also do significant water damage to a property. Sonic Fire Tech appears to be the first company trying to commercialize the science of acoustic fire suppression. Its executives have already been touring Southern California; Wednesday’s event was the first in the northern half of the state.
The company aims to make this infrasound technique mainstream in both commercial (for instance, a data center, where sprinklers would damage electronics) and in-home installations, given that sprinklers are already required in all new California homes built in 2011 and later. Sonic Fire Tech also hopes to produce a backpack-based system that could be worn by wildland firefighters headed out into the field.
The Physics Behind Acoustic Fire Suppression
Acoustic fire suppression is not a new concept. The idea that sound waves can influence flames dates back to the 19th century, when researchers observed that certain frequencies could cause a candle flame to flicker or extinguish. The underlying mechanism involves the interaction between sound waves and the combustion process. When a sound wave passes through a flame, it creates alternating regions of high and low pressure. These pressure fluctuations can physically displace the oxygen molecules from the fuel source, disrupting the chain reaction that sustains the fire. Additionally, the motion of the sound waves can increase the surface area of the flame, enhancing heat loss and further promoting extinguishment.
Most modern research focuses on low-frequency sound, typically below 100 Hz, which is capable of traveling longer distances and penetrating obstacles more effectively than higher frequencies. Infrasound, defined as sound below 20 Hz, is inaudible to humans, making it an attractive option for residential applications where noise could be a nuisance. Studies conducted by NASA and various university laboratories have demonstrated that acoustic suppression can extinguish small pool fires and even simulated grease fires, but scaling up the technology for real-world use has proven challenging.
Sonic Fire Tech claims to have solved many of those scaling problems through proprietary ducting and sensor integration. The company’s system uses strategically placed wall emitters that can direct infrasound waves toward specific zones within a room, mimicking the coverage pattern of a traditional sprinkler head. The entire system is triggered by an AI-driven smoke and heat detector that activates in milliseconds, compared to the several minutes it can take for a sprinkler bulb to burst.
Expert Skepticism: Can Sound Replace Water?
While the demonstration was visually compelling, fire protection engineers and academic experts remain cautious. Nate Wittasek, a Los Angeles-based fire protection engineer, emphasized that “sprinklers have a well-established role. They apply water directly to the fuel, cool the space, slow or stop flashover, and give people time to get out while reducing risk to firefighters. Sound may knock down a small flame, but it does not cool hot surfaces or wet fuel. That raises real questions about re-ignition, smoldering fires, hidden fires, and fires that are partially blocked by contents.”
Michael Gollner, a professor of mechanical engineering at UC Berkeley and an expert in fire dynamics, echoed those concerns. He pointed to a 2018 academic paper which found that “acoustics alone are insufficient to control flames beyond the incipient stage.” According to Gollner, “Fire sprinklers are extensively tested and certified by standards developed by the fire safety community over many years. I think this product needs to demonstrate the same or better performance with the same reliability before it can be considered to replace any existing safety measure. While I am absolutely supportive of out-of-the-box thinking, lives are truly at stake, and new technologies must carefully demonstrate effectiveness and reliability before being entrusted by society.”
The company has sought validation from third-party consultants. Sonic Fire Tech told Ars that it has been evaluated by James Andy Lynch and his team at Fire Solutions Group, a Pennsylvania-based consultancy, to establish its bona fides. However, the company declined to provide a full copy of Lynch’s report, citing “confidential and patent-pending information,” but did send a two-page executive summary. The summary states that “the Sonic Fire Tech system is capable of delivering extremely rapid fire detection, meaningful suppression or extinguishment, and consistent performance across a variety of installation configurations.” Yet the summary lacks detailed explanation of which tests were run and under what conditions, and concludes that “additional testing and optimization are recommended to further expand the range of validated applications.”
NFPA guidelines are the gold standard for residential sprinkler systems. Jonathan Hart, NFPA Technical Lead for Fire Protection Technical Resources, noted that “equivalency [to the 13D standard] can only be approved by the appropriate authority having jurisdiction and requires technical documentation be submitted demonstrating the equivalency.” To date, Sonic Fire Tech has not publicly provided this documentation.
Wildland Firefighting and Other Applications
Beyond residential and commercial structures, Sonic Fire Tech envisions its technology being used in wildland firefighting. The company hopes to produce a backpack-based system that could be worn by firefighters heading out into the field. The Contra Costa County firefighters who hosted the demonstration are curious to see more. Deputy Fire Chief Tracie Dutter told Ars that the agency does not recommend specific products, but it does try to understand the uses new technology can have. “Sonic representatives indicated they are exploring opportunities to partner with fire departments to test this technology on a bulldozer,” Dutter said. “The District would be open to testing this system on one of our dozers to better understand its limitations and potential failure points.”
For wildland applications, the challenges are even greater. Wind, uneven terrain, and rapidly spreading flames make acoustic suppression far more complex. As Gollner noted, “Outdoor fires are extremely energy-intensive and hard to control with any suppressant, let alone sound. The flame front moves quickly, and the heat release rate can be enormous.” Despite these challenges, Sonic Fire Tech’s CEO Geoff Bruder remains optimistic: “We have a roadmap for scaling our system to handle larger fires, but it will require continued research and development.”
The company also sees opportunities in protecting critical infrastructure such as data centers, where water damage from sprinklers can be as costly as the fire itself. In such environments, infrasound could offer a dry suppression method with minimal collateral damage. However, Wittasek cautions that “data centers have very specific fire risks, including electrical fires and lithium-ion battery fires, which behave differently than ordinary combustible fires. Acoustic suppression has not been proven against those types of fires.”
What Would It Take to Replace Sprinklers?
For infrasound to be considered a viable alternative to sprinklers, it must undergo rigorous testing that mirrors real-world scenarios. Wittasek outlined several conditions that should be examined: “full-scale testing that includes typical residential fires like furniture and mattress fires, cooking fires, electrical fires, and attic or exterior ember exposures. It should also cover different conditions like open and closed doors, varying ceiling heights, crosswinds, obstructed fuel packages, and whether the fire comes back after the system shuts off.”
NFPA’s 13D standard for one- and two-family dwellings requires sprinklers to provide a minimum water density over a specified area for a set duration. An equivalent acoustic system would need to demonstrate that it can deliver a comparable level of protection, including preventing flashover and keeping escape routes clear. The fact that Sonic Fire Tech has not released the full third-party validation report, and that the executive summary itself calls for more testing, leaves many questions unanswered.
Stefan Pollack, a company spokesperson, emailed Ars after the event stating, “We are making meaningful technological improvements on a monthly basis.” But until the technology can prove itself against the full range of fire scenarios that sprinklers handle routinely, the fire protection community remains unconvinced. As Hart from NFPA noted, code changes require substantial evidence and public input. Replacing an established technology like sprinklers with something novel is a multi-year process.
Nevertheless, the demonstration in Concord succeeded in drawing attention to a creative approach to fire suppression. It remains to be seen whether Sonic Fire Tech can overcome the scientific and regulatory hurdles to bring infrasound from the lab into homes and businesses.
Source: Ars Technica News