Direct Exposure of Welders to Welding Fumes and Effect of Fume Extraction Systems Under Controlled Conditions

Introduction: Welding fume exposure of welders occurs either directly from the welding process and sputters or from the fume background within the workshop. In this study the contribution of fume originating directly from the welding process was assessed. Methods: Exposure was quantified by measuring the time integral of fume mass concentration using a tapered element oscillating micro balance connected to a welder dummy. Results: Direct fume exposure was highest for welding processes with low fume emission rates and lowest for processes with high fume emission rates. Conclusions: This finding is supposed to be due to the higher energy input of high emitting processes which stabilizes the thermic column and therefore eliminates fume particles from the welder's breathing zone. Exposure can be minimized by additionally optimizing workshop ventilation.