Uncertainty analysis in the estimation of exposure

This article addresses the ubiquitous nature of uncertainty in industrial hygiene-related risk assessment and defines two basic types of uncertainly: natural variability and a basic lack of knowledge. A relatively simple physical-chemical modeling example is provided as an illustration in which uncertainty and sensitivity are described using two methods, a conventional technique and a readily available and user-friendly computer simulation software. The need for and Value of monitoring data for validation and as a ''reality check'' is emphasized.