Tariff classification of electrostatic precipitators favours the specific heading over broader alternative customs headings.

Electrostatic precipitators imported for use in power plants were held classifiable under Heading 84.18 because the tariff contained a more specific entry covering those goods by name and description. They were not treated as air filters under Heading 84.17, nor as auxiliary boiler plant or machinery for treatment of materials under Headings 84.01/02, as those headings did not aptly describe the goods. The specific heading prevailed over broader alternatives in the tariff structure, so the customs classification adopted by the authorities was upheld and the importer's claim failed.

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Issues: Whether electrostatic precipitators imported for use in power plants were correctly classifiable under Heading 84.18 rather than under Headings 84.17 or 84.01/02.

Analysis: The imported goods were not air filters meant to supply purified air into a machine or combustion chamber, nor were they auxiliary boiler plant or machinery for treatment of materials by a process involving change of temperature. The more specific tariff entry for electrostatic precipitators, supported by the explanatory notes and the structure of the tariff, covered the goods. Where a specific heading squarely covered the goods, it had to prevail over the broader and less apt headings claimed by the importer.

Conclusion: The goods were classifiable under Heading 84.18 and not under Headings 84.17 or 84.01/02; the assessment made by the customs authorities was in substance and the importer's claim failed.

Final Conclusion: The customs classification adopted by the authorities was upheld, and the importer obtained no relief.

Ratio Decidendi: In tariff classification, a specific entry covering the goods by name or clear description prevails over broader headings that do not aptly describe the goods.

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