EPA-Expo-Box (A Toolbox for Exposure Assessors)
Initial exposure assessments, including screening-level assessments, usually begin with a deterministic approach that uses point values and simple models to produce a point estimate of exposure (either high-end or typical exposure). Refined assessments also often use deterministic models with site-specific data. Deterministic assessments are simple to carry out, often use readily available data, and produce results that are straightforward to interpret.
Probabilistic assessments use more complicated modeling approaches that rely on distributions of data as inputs in place of point values for key parameters. This results in a distribution of possible exposure estimates and greater ability to characterize variability and uncertainty.