Similar values of respirable dust fraction concentrations
were obtained in the samples collected in the
breathing zone of welders simultaneously on a membrane
filter and a glass fibre filter (r = 0 75-0 98).
Mean weighted total Cr concentration in the
breathing zone ofwelders ranged from 0-005 to 0-991
mg/m3 (fig 2). The highest total Cr concentration was
found in plants A and B in which the work was
performed in a half closed area without local exhausts
and in a forced body position.
Figure 3 presents the content of particular
elements of fumes. The data indicate that the
chemical content of fumes in the breathing zone of
welders varied greatly. Total Cr in the fumes occurring
in the breathing zone of all welders ranged from
O-1% to 7-4%. Mean values of total Cr (%) in plants
A, B, C, and D were 3 4%, 2-5%, 1e4%, and 2-6%
respectively.