Argon is recovered as a byproduct during the cryogenic distillation of air, primarily at facilities co-located with or supplying large steel mills, petrochemical plants, or dedicated air-separation units. When these facilities reduce output — due to energy costs, demand downturns, or maintenance — argon production falls proportionally, which can tighten supply and elevate prices even when demand for argon itself is stable.

All argon, regardless of purity grade (industrial, welding, or ultra-high-purity), is classified under the single line 2804210000. However, purity grade is a critical commercial specification: semiconductor and laser applications require ultra-high-purity argon (99.999%+), while welding applications typically use standard industrial grades. Purity must be confirmed in supplier documentation even though it does not change the HTS classification.