“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,” he added. “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.”

Similarly, 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 emailed Ars. “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.”

Dozer time

As for the Contra Costa County firefighters who hosted the demonstration, they 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 that 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,” Dutter added, 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.”