Heavy metals in welder's working environment

The knowledge is summed up of the origin of welding aerosols. It is stated that the maximum production of welding fumes occurs at maximum electric current of the arc. The fumes are generated from the lower part of the surface of the low-temperature arc plasma. With the decreasing diameter of aerosol particles increases enrichment with toxic elements. Filtration method is most frequently being used for determining aerosols. Samples of toxic aerosols are taken using a portable sampling chamber. The SYNPOR 4 membrane filter was chosen for filtration. The filter was dried for 2 hours prior to use at a temperature of 90 to 110 degC. In the chemical analysis of aerosols attention is devoted mainly to radioanalytical methods. Neutron activation analysis is a significant and most frequently used method. Published results of analyses of polluted air are discussed. The analysis of welding fumes places main emphasis on the determination of Cr(VI). The second most widely used is X-ray fluorescence analysis. Tables show the results of the analysis of welding aerosols at different welding currents. Graphically shown is the content of heavy metals in welding aerosols at different welding currents for the E-R 428 rutile coated electrode. Electrodes E-B 427 and E-B 466 were used for manual arc welding of high alloy steel. (E.S.)