PEL, defined

The OSHA-PEL defines the average concentration permissible to a worker for a normal eight-hour workday and a 40-hour work week to... 

Although a few occupationally-exposed workers in the studies presented in Table 8 exhibit CDU levels below 3 jg/g CRTU, most of those workers exposed to cadmium levels in excess of the PEL defined in the final cadmium rule exhibit CDU levels above 3 pg/g CRTU this level represents the upper 95th percentile of the CDU distribution observed among those who are not occupationally exposed to cadmium (Table 7). 

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