The industrial hygiene of uranium refining.

Uranium refining operations and equipment are described, and a study of occupational exposure to uraniumhearing dust is reported. The total of refinery personnel rose from 400 in 1948 to 500 in 1954 and 3000 in 1960, Data on exposure to alpha -emitting dust are cited and arranged to show that that in 1948 almost all the workers were exposed to greater than present permissible air-dust levels, By 1955 only two operations led to excessive exposures. In 1948 and 1949 exposures were 400 times the present acceptable levels; by 1955 this amount was reduced to 4 times the admittedly conservative permissible level of 110 d/nrin/ Cu. m. (T.R.H,)