The flexible Fire Detection Tubing (FDT) is installed directly inside the extractor hood-directly above cooking areas. When a fire occurs, the point on the pressurized FDT nearest the heat source will burst at 175 deg C. The Sudden tube depressurization actuates the special pressure differential valve and instantly floods the cooking area with Class F extinguishing agent. The fire is quickly suppressed just moments after it began… minimizing damage and downtime.