Chromium, nickel and manganese in shipyard welding fumes

Tests were conducted to determine the effects of base metal and welding electrode composition on welding fume. Materials included HY-100 and HSLA-100 high-strength, low-alloy steels. Shielded metal are welding (SMAW) was performed with E11018-M electrodes and gas metal are welding (GMAW) with MIL-100S-1 electrode wire. These tests included measurement of fume composition, fume generation rates and worker breathing zone fume. Sampling of welding fume also was conducted in a shipyard. This study concludes that some shipyard welding and cutting operations, materials and processes will be impacted by the recent and anticipated reductions in exposure limits. Additional controls will be required to comply with these reductions. Results indicate: Exposure to hexavalent chromium can be expected when welding or cutting materials that contain chromium or chromates. These materials include stainless steels, high-chromium nickel alloys and some low-alloy steels. The highest nickel levels occurred during SMAW and GMAW of stainless steels and nickel alloys. However, only the samples in enclosed spaces exceeded the proposed limit for nickel. SMAW, GMAW and flux cored are welding (FCAW) of stainless steels, carbon steels and low-alloy steels produced the highest manganese levels. Eight-hour TWA levels of hexavalent chromium of up to 1-2 mu g/m(3) were found during shipyard and laboratory sampling of SMAW of HY-100 using E11018-M and E12018-M electrodes. Similar levels also may be possible when welding with these electrodes on other materials.