Section 06 PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES 28 Inorganic chemicals; organic or inorganic compounds of precious metals , of rare 28 11 Other inorganic acids and other inorganic oxygen compounds of non-metals. Commodity Code Description 28 11 11 Hydrogen fluoride (hydrofluoric acid) 28 11 12 Hydrogen cyanide (hydrocyanic acid) 28 11 19 28 11 21 28 11 22 28 11 29