... protection gas for chemical industry, metallurgy, and electric industry.Industrial hydrogen ≥99.9GB-T3634-1995CylinderChemical industry, glasses, synthetic cut stone.Industrial carbon ... , protectionPure Nitrogen≥99.996GB/8979-96CylinderChemical industry, glasses, smelting, protectionCarbon Monoxide ≥99.9Q/DY01-98CylinderChemical industry, medical, analysisHigh Purity Hydrogen ≥99 ...