HS 281122 Silicon dioxide

What products does HS 281122 cover?

This subheading covers silicon dioxide, also known as silica, in its various forms, provided it meets the purity requirements for Chapter 28 and is not otherwise specified elsewhere in the Harmonized System. This includes naturally occurring forms like quartz, sand, and flint, as well as synthetic amorphous silica, fumed silica, and precipitated silica, when presented as chemically defined compounds. The WCO Harmonized System Explanatory Notes for Heading 2811 clarify that this heading encompasses non-metallic inorganic acids and non-metals oxides, with silicon dioxide specifically enumerated. The USITC Harmonized Tariff Schedule and EU TARIC system both align with this scope, classifying pure silicon dioxide under this specific subheading.

What falls outside HS 281122?

The following products are excluded from HS 281122: silica in a form or purity that does not meet the criteria for chemically defined inorganic compounds of Chapter 28. For instance, silica sands used in foundry work or glass manufacturing, which are typically impure and processed for their physical properties rather than chemical composition, are generally classified under Chapter 25, specifically subheading 2505. Similarly, silica gels, which are porous forms of silicon dioxide used as desiccants or chromatographic media, are classified under Heading 3824 as prepared binders for foundry moulds or cores; chemical products and preparations of the chemical or allied industries (including those consisting of mixtures of natural products), not elsewhere specified or included. Furthermore, certain forms of silicon dioxide combined with other materials, such as in ceramic products or optical elements, would be classified according to their composite nature and primary function.

What are common classification mistakes for HS 281122?

A common error is misclassifying impure forms of silicon dioxide, such as industrial silica sand, under HS 281122 instead of Chapter 25. Importers often overlook the "chemically defined" requirement for Chapter 28, leading to incorrect classification. Another frequent mistake involves silica gels, which, despite being primarily silicon dioxide, are functional products classified under Heading 3824 due to their specific applications as desiccants or catalysts, rather than as a pure chemical compound. Applying General Interpretative Rule (GRI) 1, which states that classification shall be determined according to the terms of the headings and any relative Section or Chapter Notes, is crucial. For silicon dioxide, the purity and intended use significantly influence whether it remains in Chapter 28 or moves to other chapters based on its form or function.

How should importers classify products under HS 281122?

The correct procedure for classifying silicon dioxide involves a thorough review of its chemical purity, form, and intended use. Importers and customs brokers should first ascertain if the product is a chemically defined silicon dioxide, meeting the purity standards for Chapter 28. If it is an impure form, such as silica sand for industrial use, it likely belongs in Chapter 25. For products like silica gel, even if chemically pure silicon dioxide, their functional nature dictates classification under Heading 3824. Consulting the WCO Harmonized System Explanatory Notes for Heading 2811 is essential for detailed guidance. Furthermore, obtaining a laboratory analysis or a manufacturer's declaration confirming the chemical composition and purity can provide definitive evidence to support the classification under HS 281122, ensuring compliance with USITC and EU TARIC regulations.