Gas shielded welding (l) density of gas shielded arc  Welding Electrodes, arc, high temperature and high concentration of harmful CO2 Gas Shielded Welding Wire in the high temperature arc and strong ultraviolet rays, can be as high as manual metal arc welding 4 ^ -7 times, it is particularly attention to ventilation. (2) arc used in high-frequency oscillator will produce a certain intensity of electromagnetic radiation, welders, more contact may cause dizziness, fatigue, weakness, palpitations and other symptoms. (3) Mu, persimmon and other rare metals in the hydrogen arc welding tungsten materials radioactive, especially in the form of radioactive dust when grinding electrode contacts are more likely to cause a variety of welders disease.