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Uses. Oxygen is of great importance in the chemical and the iron and steel industries. Its major use is in steel production, for example in the Bessemer process. The oxyacetylene torch is another important industrial application.Oxygen is utilized in medicine in the treatment of respiratory diseases and is mixed with other gases for respiration in submarines, high-flying aircraft, and spacecraft.ts major use is in steel production, for example in the Bessemer process. The oxyacetylene torch is another important industrial application. Oxygen is utilized in medicine in the treatment of respiratory diseases and is mixed with other gases for respiration in submarines, high-flying aircraft, and spacecraft.
Because it is very unreactive, helium is used to provide an inert protective atmosphere for making fibre optics and semiconductors, and for arc welding. Helium is also used to detect leaks, such as in car air-conditioning systems, and because it diffuses quickly it is used to inflate car airbags after impact. A mixture of 80% helium and 20% oxygen is used as an artificial atmosphere for deep-sea divers and others working under pressurised conditions. Helium-neon gas lasers are used to scan barcodes in supermarket checkouts.