In California, a small fire in a test kitchen is giving fire safety engineers and firefighters a closer look at an unusual idea: putting out flames with sound instead of water. During a recent demo, an overhead AI-powered sensor picked up signs of trouble and triggered wall-mounted emitters that blasted low-frequency infrasound toward the stovetop. Within a few seconds, the flames went out. The company says this is not just a lab trick but a preview of a full building system that could replace t