Blue light emitted from the arc welding process can cause photoretinopathy. Since the hazard level of blue light depends upon the welding variables, it is important to identify the hazard levels of blue light under various conditions. Here, we experimentally evaluated the hazard levels of blue light emitted from the tungsten inert gas (TIG) welding of aluminum alloys. In addition, the protective performance of filter plates and automatic welding filters that complied respectively with the Japanese Industrial Standard (JIS) and Welding Engineering Society Standard (WES) were considered.

In this study, the hazard level of blue light is evaluated in terms of effective blue light radiance defined in the American Conference of Governmental Industrial Hygienists Guidelines. We have measured the effective blue light radiance in the range of 1.17.3 W/(cm²･sr). The measured effective blue light radiance is observed to depend upon the type of electrode used and increases with increase in welding currents. We thus suggest that the hazard levels of blue light emitted from TIG welding of aluminum alloys can be sufficiently reduced using a JIS T8141 filter plate and a WES 9010 automatic welding filter.