Abstract
The purpose of the study was to compare gas-metal-arc welding with covered-electrode welding and to determine if ventilation requirements for the two processes should be different. Solenoid valves set for inhalation and exhalation times observed in the normal adult male were used to simulate breathing by a plaster dummy head. The plaster head, mounted on an automatic welding head carriage, moved parallel to the welding direction so that its position remained fixed relative to the welding arc. Air samples were taken concurrently inside and outside the helmet worn by the dummy during the welding process. Samples were analyzed for concentrations of iron oxide, nitrogen dioxide, ozone, fluorides, and carbon monoxide. Combinations of five wire electrodes, three of which were flux-cored, and five shielding gases were evaluated. One type of coated-rod electrode was used for comparison purposes.
