In this study, the gas tungsten arc welding (GTAW) technique was used to weld samples of three materials: SS304-type stainless steel, A36 low-carbon steel, and 16061 aluminum. The welding was applied at 200 A, and the radiation types and luminosities were measured for each material. During the welding processes, UV radiation was the most frequently observed in all parameters; in addition, visible light and IR radiation, 200-1000 nm on an optical scale, were recorded. The effects of electric currents on the photon energy rates were clearly exhibited. The production and type of radiation (photon energy and high-frequency energy) were affected by the GTAW applications using tungsten electrodes containing 2% thorium, thus corroborating previous findings in the literature.