Section 06 Products of the chemical or allied industries 28 Inorganic chemicals; organic or inorganic compounds of precious metals, of rare - earth metals, of radioactive elements or isotopes 28 04 Hydrogen, rare gases and other non-metals Commodity Code Description 28 04 10 Hydrogen 28 04 21 Argon 28 04 29 Other 28 04 30 Nitrogen 28 04 40 Oxygen 28 04 50 Boron; tellurium 28 04 61 Containing by weight not less than 99.99% of silicon 28 04 69 Other 28 04 70 Phosphorus 28 04 80 Arsenic 28 04 90 Selenium
