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As part of a Canada-wide study of women entering non-traditional trades [Women’s Health in Apprenticeship Trades – Metalworkers and Electricians (WHAT-ME)], we examined spot urine samples from women welders in Alberta to determine whether urinary metal concentrations exceeded those of the general population, to compare levels to previously published urinary concentrations in male welders and to examine the relationship with welding tasks. Women mailed-in urine samples collected close to the time of completing a detailed exposure questionnaire, including welding tasks on their most recent day welding at work. Of 53 welders working in their trade, 45 had urinary creatinine >0.3–≤3.0g l−1 and were included in analyses. Seven metals were examined for which both population and male welder urinary concentrations were available: cadmium, chromium, cobalt, copper, manganese, nickel, and zinc. Principal component analysis was used to extract three components from natural log transformed creatinine-corrected metal concentrations. Of the 45 women, 17 reported more than one main task. Overall two thirds worked in fabrication, a third on pipe welding, and smaller numbers on repair, in construction or other tasks: manual metal arc welding was reported by 62%, semi-automatic arc welding by 47%, and arc welding with a tungsten electrode by 15%. In multiple regression analyses, little relation was found between urinary metals and task or type of welding, except for cadmium where lower levels were seen in those reporting semi-automatic manual welding (after adjustment for age and smoking). The proportion of women welders exceeding the selected general population 95th percentile was high for manganese (96%) and chromium (29%). Urinary metal concentrations were similar to those reported for male welders with only manganese, with a geometric mean in women of 1.91 µg g−1 creatinine, and perhaps copper (11.8 µg g−1 creatinine), consistently lower in male welders. Although not evident from the task analysis reported here, differences in exposure by sex may be explained by type of welding or by other work practices. A closely comparable cohort of male welders would be necessary to examine this hypothesis more fully. [ABSTRACT FROM AUTHOR]

Predictions have been made of anode melting for free- burning arcs by making two -dimensional calculations of temperature profiles of the arc and the electrodes to make predictions of weld depth and weld shape in arc welding. Predicted properties at 150 A, for various arc lengths, are compared with experimental results of: 1) weld shape; 2) heat intensity as a function of radius; and 3) current density as a function of radius at the anode. The whole region of the arc system is modeled, including the tungsten cathode, the arc plasma and the solid and molten anode, including convection within the molten weld-pool. Theoretical and experimental it suits are also obtained for high- and low-sulfur steel, which have markedly different surface tension properties of the molten liquid, resulting in weld depths that differ by a factor of three because of changed convective circulation properties hi the weld pool. Although total power to the anode increases with increasing electrode separation, the current density becomes less, with the result that for electrode distances above 2 mm, for argon, the width and depth of the molten region become less, in agreement with experimental it-suits that we have obtained. [ABSTRACT FROM AUTHOR]

Professional commercial divers working with electrical cutting and welding sometimes experience, a metallic taste phenomenon. An enquéte study among divers showed no influence of different equipment on the occurrence of such metallic taste, but it seems to occur less frequently in low salinity water. It has been suggested that this metallic taste phenomenon is due to increased corrosion rate of dental restorations, especially of amalgam. Experimental results recording the potential of amalgam specimens placed in the oral cavity of divers during welding, showed influence on the potential, and thus probably on the corrosion rate, during welding only when the diver came into direct contact with the water, e.g. through leakage in the suit. [ABSTRACT FROM AUTHOR]