HS Code for Perfluorooctane sulfonic acid

Perfluorooctane sulfonic acid (PFOS) is classified under HS code 2904.31. This substance is an organic chemical belonging to the sulfonated derivatives of hydrocarbons. Chapter 29 covers organic chemicals, and heading 2904 specifically addresses derivatives containing sulfonated, nitrated, or nitrosated groups. The subheading 2904.31 was created to facilitate the monitoring of PFOS, which is a persistent organic pollutant (POP) regulated under the Stockholm Convention. Classification is based on the chemical structure: a fully fluorinated eight-carbon chain attached to a sulfonic acid group. This code applies to the acid form of the chemical. Because of its high level of regulation, customs authorities require precise documentation to distinguish the pure acid from its salts or other derivatives. The classification follows GRI 1, as the subheading explicitly names perfluorooctane sulfonic acid.

Products Included

• Perfluorooctane sulfonic acid (PFOS)
• Heptadecafluorooctane-1-sulfonic acid
• Perfluorooctane sulfonate (acid form)
• Pure PFOS chemical samples
• Fluorinated hydrocarbon sulfonated derivatives

Common Misclassification

PFOS is often confused with its salts, such as ammonium perfluorooctane sulfonate, which is classified under HS code 2904.32. Other salts like lithium, potassium, or zinc salts of PFOS fall under codes 2904.33 through 2904.36. Another common misclassification is HS code 3824.99, used for industrial chemical mixtures. If PFOS is part of a fire-fighting foam or a textile treatment solution, it is no longer a separate chemically defined compound and must be classified in Chapter 38. Finally, it should not be confused with PFOA (Perfluorooctanoic acid), which is a carboxylic acid classified in heading 2915.

FAQ

What is the HS code for PFOS?

The HS code for the acid form of perfluorooctane sulfonic acid is 2904.31.

Are PFOS salts classified under the same code?

No, salts of PFOS are classified in separate subheadings ranging from 2904.32 to 2904.36, depending on the specific cation (e.g., ammonium, lithium).