Explanatory notes
… sulphonic acid, its salts and perfluorooctane sulphonyl fluoride : 2904.31 ‑ - Perfluorooctane sulphonic acid … sulphonic acid 2904.36 ‑ - Perfluorooctane sulphonyl fluoride - Other : 2904.91 ‑ - … and use of PFOS, its salts and perfluorooctane sulfonyl fluoride (PFOSF) is controlled by the Stockholm Convention …