Weld fume can be one of those hazards which isn’t easily identified, but TIG welding is different than most arc welding processes in that it does not produce very much fume. We can use this lack of fume to our advantage and use TIG welding instead of other types of arc welding to prevent exposures to harmful weld fume.
2. Where is TIG welding used to reduce fume exposures?
The TIG process is sometimes used when welding stainless steel to reduce the welder’s chance of overexposure to hexavalent chromium. Chromium in the steel is changed from the less harmful trivalent form to the hexavalent form, which is carcinogenic. This transformation occurs when it is energized by the electric arc.
3. Can overexposure to hexavalent chromium occur during TIG welding of 4130 Chrome-Moly?
Due to the low chromium content of 4130 Chrome-Moly and the low fume producing characteristic of TIG welding it is unlikely overexposure to hexavalent chromium would occur.
4. What is the most common hazard ignored by TIG welders?
Surprisingly, from my experience the most common hazard ignored by TIG welders is the ultra-violet (UV) light emitted from the arc. Welders are very good about protecting their eyes. However, they sometimes forget that repeated skin exposure to the intense light not only causes a tan, but also damages their skin just like prolonged sun exposure. Be sure to always cover your arms and the lower part of your neck when TIG welding.5. What about UV light exposures to non-welders in the work area?
Those not welding should be protected from accidental viewing of the arc by solid shields or curtains made for the purpose of filtering the light. They may not know when you’re about to strike an arc so ensure there isn’t a direct line of sight between your work piece and non-welders.
6. Are there any gases of concern produced by TIG welding?
Especially when welding metals that are very reflective there is the potential for ozone to be created during TIG welding. Ozone is a respiratory system irritant and has a low occupational exposure limit. Adequate ventilation during this process is key.
If there is a welding health and safety item you would like see covered in this new column please let us know! You won’t be the only one that will learn something; many others probably are wondering the same thing.
Kevin Sayler, CIH is a health and safety consultant who helps businesses increase profitability by reducing costs associated with workplace accidents, injuries and diseases. He specializes in the prevention of harmful exposures to employees.
Ph: (360) 420-2985