Research-Grade Krypton
Research-grade krypton with ultra-high purity (>99.999%) for spectroscopy and particle physics experiments is a chemically defined rare gas under heading 28.04. It meets Chapter 28 Note 1(a) as a separate element, with no added substances, and is not doped for electronics per Chapter 28 Note 8.
Import Duty Rates by Country of Origin
| Origin Country | MFN Tariff | Surtaxes | Total Effective Rate |
|---|---|---|---|
| 🇨🇳China | Free | — | Free |
| 🇲🇽Mexico | Free | — | Free |
| 🇺🇸United States | Free | — | Free |
| 🇩🇪Germany | Free | — | Free |
| 🇯🇵Japan | Free | — | Free |
More Specific Codes
This product may fall under a more specific subheading:
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If the gas is mixed with other gases for calibration or research
Mixtures not meeting Chapter 28 Note 1 criteria may fall under Chapter 38.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right tariff item — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Document the purity level (>99.999%) with a certificate of analysis
• Ensure the gas is not mixed with other gases; pure krypton is required for classification
• For research use, consider if any end-use certificates are needed for duty relief
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