The portable oil-water interface detector is suitable for measuring the oil-water interface and temperature of various oil tanks and dirty oil-water tanks, as well as for measuring the oil-water interface and temperature in other occasions. According to Article 32 of MEPC 51/22/Add. 2, oil tankers of 150 gross tons and above shall be equipped with effective oil-water interface detectors recognized by the competent authority, in order to quickly and accurately determine the oil/water interface. Other tanks that require oil-water separation and intend to discharge the effluent directly into the sea shall also be equipped with such detectors.