A Field Evaluation of a Mathematical Model to Predict Worker Exposure to Solvent Vapors

Abstract

A mathematical model of exposure developed from simple conceptual ideas of air flow around a worker and dimensional analysis is evaluated with field data. The observed job was selected to match closely the assumptions used in the derivation of the model. Predicted mean exposure errors were −52 percent and +28 percent for the two individuals performing the same job. A total of approximately 190 8-hour time-weighted average samples were collected on two individuals to estimate mean exposures. The generation rate of contaminant, the proximity of the worker to the source of pollution, and the air flow field are critical variables. A successful modeling effort must address these factors in a comprehensive way. The higher exposure of the smaller worker is predicted by the model, but given considerable confounding with work practices, this size effect remains to be validated.