The article explains how inline sound-velocity measurement can prevent misfills during liquid transfers by identifying incoming products in real time. By measuring the speed of sound through a liquid and comparing it against a temperature-compensated reference profile for known products, facilities can verify product identity at transfer points, stop incorrect connections before they occur, and reduce contamination, downtime, and safety/environmental risks. The approach can be integrated with existing instrumentation (for example, ultrasonic sensors) and control systems, reducing reliance on manual checks and lab sampling, though it requires a robust reference database, proper temperature compensation, and awareness that mixtures or off-spec blends may complicate identification.