ABSTRACT
This chapter explains the role of vapor pressure in determining a chemical's evaporation rate, and the role of evaporation rate in determining that chemical's airborne concentration in either unventilated, ventilated, or outdoor settings. It subdivides accumulation scenarios by how much liquid is initially present to evaporate. The chapter briefly introduces each of four settings in the order from the simplest to the most complex, to be followed by more detailed discussions within several subsequent sections. The principle used to predict the worst-case vapor concentration resulting from the incomplete evaporation of a large volume of liquid within a closed room is so fundamental to IH that it should be thoroughly understood. This chapter starts by introducing the Environmental Dilution Ratio or EDR, a novel but powerful way to view the steady-state airborne concentration that results from nearby evaporation.
