Section 18 Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; clocks and watches; musical instruments; parts and accessories thereof 90 Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; parts and accessories thereof 90 30 OSCILLOSCOPES, SPECTRUM ANALYSERS AND OTHER INSTRUMENTS AND APPARATUS FOR MEASURING O 90 30 10 Instruments and apparatus for measuring or detecting ionising radiations Commodity Code Description 90 30 10 00 Instruments and apparatus for measuring or detecting ionising radiations