Exposure Assessment;http://www2.epa.gov/laws-regulations/laws-and-executive-orders

Exposure Assessment;http://www2.epa.gov/laws-regulations/laws-and-executive-orders Exposure assessment can be difficult.  In Table 3-4 of your "Dimensions..." reading a hierarchy of exposure is presented.  In a worker population, what would be the advantages and disadvantages of using data types 1-3.  No more than 4 pages.