... > SECTION VI - PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES > CHAPTER 29 - ORGANIC CHEMICALS > I. HYDROCARBONS AND THEIR HALOGENATED, SULPHONATED, NITRATED OR NITROSATED DERIVATIVES > 2904 Sulphonated, nitrated or nitrosated derivatives of hydrocarbons, whether or not halogenated > Perfluorooctane sulphonic acid, its salts and perfluorooctane sulphonyl fluoride > Other salts of perfluorooctane sulphonic acid