| Machine/Metal construction |
| Oxygen |
Used
in combination with a fuel gas (such as acetylene) for cutting and welding |
| Nitrogen |
Heat
treatment of various metals |
| Argon |

Protection of welds against oxidation, reduction of welding emissions |
| Hydrogen |
Heat
treatment of various metals |
| Carbon dioxide |
Shielding
of welds against oxidation |
| Acetylene |
Cutting
and welding (with oxygen) |
Performance
Health
Safety
Environment |