... and protection gas for chemical industry, metallurgy, and electric industry.hydrogen≥99.9GB-T3634-1995bottle/cylinderChemical industry, glasses, synthetic cut ... , high-altitude weather balloon used in chemical industry.pure Helium≥99.995GB/T4844.2-1995bottle/cylinder Electronic ... industry, chemical industry, analysis Pure argon ≥99.99 GB/T4842- ...