Tariff classification of ATP hygiene testing device upheld under the heading for other measuring instruments, not light meters.

An ATP-based hygiene testing instrument was treated as classifiable under Heading 9031.80 as an other measuring or checking device, because its principal function was to detect contamination or cleanliness levels by measuring light emitted in a biochemical reaction, not to measure illumination as a luxmeter or other light-measuring instrument. Heading 9027 was found inapplicable since the product did not measure quantities of light in the relevant tariff sense, and its reference to separate instrument categories did not extend to this device. The applicable classification therefore remained under the residuary heading for other instruments, and the challenge to classification under Heading 9027 was rejected.

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Issues: Whether the imported instrument used for ATP-based hygiene testing was correctly classified under Heading 9031.80 as an other measuring or checking device, or under Heading 9027 as an instrument for measuring or checking quantities of light.

Analysis: The instrument was found not to be a luxmeter and did not measure illumination in units of light. Its working was to measure light emitted in a biochemical reaction involving ATP and luciferase, and that measurement was translated into relative readings indicating contamination or cleanliness levels of surfaces and liquids. Heading 90.27 was noted to contain separate categories, and the third category relating to light-measuring instruments did not cover the imported product. The reference to refractometers in the first category did not justify placing this product in the light-measuring category. Since the goods were not light meters and were instead used to determine contamination levels, the residuary heading for other instruments was held to be the appropriate classification.

Conclusion: The classification under Heading 9031.80 was upheld and the challenge to classification under Heading 9027 was rejected.

Final Conclusion: The imported equipment was treated as a hygiene testing instrument rather than a light-measuring instrument, and the departmental classification was sustained.

Ratio Decidendi: For tariff classification, the goods must be classified according to their principal function and specific description, and a device that measures emitted light only as a means to detect contamination is not classifiable as a light-measuring instrument.

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