The most common source of argon (Ar, R-740) is an air separation plant where crude argon is further purified to produce the various commercial grades required. It is a colourless and odourless gas that is non-reactive and inert. Recommended regulator W019110 or W019210.

Applications

Argon is widely used as a shielding gas for arc welding and is one of the most common carrier gases in gas   chromatography. Also used as a carrier gas in sputtering, plasma etching and ion implantations, and as a blanket atmosphere in crystal growth. Other applications include ICP spectroscopy; atomic absorption spectrometry; for filling incandescent lamps; as a thermal insulation gas; to refine stainless steel and prevent oxidation of molten metals and alloys; and various others.