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, the state’s premier wildland firefighting agency (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 Science of Acoustic Fire Suppression
The principle behind acoustic fire suppression is based on the fact that sound waves are pressure waves that can disturb the air around a fire. At low frequencies, typically below 20 Hz (infrasound), the waves have long wavelengths that can travel through obstructions and affect a larger volume of air. When these waves interact with a flame, they cause vibrations that physically push oxygen molecules away from the fuel. Without oxygen, the combustion reaction cannot sustain itself, and the flame is extinguished. This phenomenon has been studied in laboratories for decades, but practical applications have been limited by the difficulty of generating enough acoustic energy to suppress larger fires.
Sonic Fire Tech claims to have solved this challenge by developing powerful, compact emitters that can be mounted on walls or ceilings and integrated with AI-driven detection systems. The company’s system uses a network of sensors that identify the heat signature and location of a fire in milliseconds, then direct focused infrasound beams toward the source. In the demonstration, the system successfully extinguished a small cooking fire within seconds.
Potential Advantages Over Water Sprinklers
Water sprinklers have been the standard for fire suppression for over a century. They work by applying water directly to the burning material, cooling it below the ignition temperature, and also wetting surrounding surfaces to prevent fire spread. However, sprinklers have several drawbacks: they can flood a building, damaging electronics, furniture, and documents; they require extensive plumbing infrastructure; and they typically activate only after heat has risen to a threshold, which can take several minutes.
Sonic Fire Tech promotes infrasound suppression as a solution that addresses these issues: no water damage, no chemical residue, instant activation, and lower installation cost. The company’s press releases claim that “Sonic Home Defense… deploys in milliseconds and uses inaudible low-frequency infrasound waves to disrupt the chemistry of combustion before flames can spread, with no water, no chemicals, and no risk of flooding.”
For critical environments like data centers, server rooms, and laboratories, water suppression can be disastrous. Infrasound offers a potential alternative that could save both hardware and data. Similarly, in historic buildings or museums, water damage from sprinklers could destroy priceless artifacts. Acoustic suppression might preserve these items while still protecting against fire.
Expert Skepticism and Concerns
Despite the promising demonstration, fire safety experts have raised serious questions about the technology’s readiness to replace sprinklers. Nate Wittasek, a Los Angeles-based fire protection engineer, noted: “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.”
Re-ignition is a particular concern: in the demonstration, the infrasound was applied while the fire was still small. But in a real home fire, the heat may have already transferred to surrounding materials. If the acoustic source cuts off, the hot pan or grease could re-ignite from residual heat. Sprinklers, by contrast, continue to cool the area with water, preventing re-ignition.
Another issue is hidden fires. Fires can start inside walls, attics, or behind appliances where sound waves may not reach effectively. Water from a sprinkler can penetrate these spaces through gaps and wet the material. Infrasound, however, requires a direct line of sight or at least a clear path for the waves to propagate.
Michael Gollner, a professor of mechanical engineering at the University of California, Berkeley, and an expert in fire dynamics, told Ars there’s simply not enough information yet to show that this technology works better than sprinklers. He pointed to a 2018 academic paper, which found that “acoustics alone are insufficient to control flames beyond the incipient stage.” By contrast, “Fire sprinklers are extensively tested and certified by standards developed by the fire safety community over many years,” he said. “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.”
Testing and Certification Gaps
Sonic Fire Tech claims to have secured third-party validation of its system as a viable NFPA 13D-equivalent alternative. The company provided Ars with a two-page executive summary from Fire Solutions Group, a Pennsylvania-based consultancy. 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.” However, it also concludes that “additional testing and optimization are recommended to further expand the range of validated applications.”
Critically, the summary lacks detailed information about the test protocols, fire scenarios, and success criteria. Jonathan Hart, NFPA Technical Lead, Fire Protection Technical Resources, clarified that equivalency to the 13D standard can only be approved by the authority having jurisdiction, and requires full technical documentation. Sonic Fire Tech has not publicly released this documentation.
Wittasek emphasized: “I would want to see 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.”
The company has not yet submitted its system for formal certification by a recognized testing laboratory like UL (Underwriters Laboratories) or FM Global. Such certification is standard for any fire suppression product intended for widespread use.
Wildland Firefighting Application
Beyond residential and commercial use, Sonic Fire Tech is exploring a backpack-mounted system for wildland firefighters. Wildland fires are often fought in remote, rugged terrain where water supply is limited. If an infrasound backpack could knock down small spot fires or cool hot spots ahead of a fireline, it might provide a valuable tool. However, experts are even more skeptical about this application. Wildland fires can grow extremely fast, driven by wind and heavy fuel loads. A single backpack unit would likely be insufficient to suppress even a small crown fire.
Deputy Fire Chief Tracie Dutter of Contra Costa County Fire Protection District said the agency is open to testing the system on a bulldozer. “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.” With new tech like this, firefighters also want to understand what long-term maintenance requirements it has, whether routine testing or calibration is required to ensure reliability, and how system failures such as a malfunctioning detector or acoustic generator are identified and communicated to an owner.
Historical Context of Acoustic Fire Suppression
The concept of using sound to extinguish fire is not new. In the 19th century, John Tyndall (the physicist known for the Tyndall effect) demonstrated that a flame could be extinguished by a loud note from an organ pipe. Later, NASA and other agencies experimented with acoustic suppression in microgravity, where convection currents are absent and sound waves can be more effective. However, scaling up to Earth-based fires has proven difficult because the energy required to suppress a large fire is immense. Sonic Fire Tech claims to have overcome this by using infrasound at specific frequencies that resonate with the flame structure, maximizing energy transfer.
Other approaches to non-water fire suppression include inert gas systems (like those in server rooms) and chemical foams. These all have their own drawbacks: gases can suffocate people if not vented properly, and foams leave residue and can be environmentally harmful. Infrasound, if proven effective, would be clean and safe for humans (infrasound is inaudible and not known to cause harm at the levels used).
Path Forward
Sonic Fire Tech has generated interest and curiosity among firefighters and property owners. The company continues to refine its system and seeks partnerships for further testing. “We are making meaningful technological improvements on a monthly basis,” Stefan Pollack, a company spokesperson, said after the event.
For the technology to gain acceptance, it must undergo rigorous, independent testing against established standards. The fire protection community is open to innovation but rightly cautious about technology that could put lives at risk if it fails. As Gollner noted, “lives are truly at stake, and new technologies must carefully demonstrate effectiveness and reliability before being entrusted by society.”
In the meantime, the Contra Costa County Fire Protection District will watch the development closely. Deputy Chief Dutter emphasized that her agency does not recommend specific products but tries to understand potential uses. She confirmed the district would be willing to test the infrasound system on a bulldozer, a first step toward evaluating its capabilities in a real-world wildland firefighting context.
Whether infrasound ever replaces sprinklers remains to be seen. For now, it remains an intriguing experimental technology with great hopes and great hurdles.
Source: Ars Technica News