Evaluating indoor exposure modeling alternatives for LCA: A case study in the vehicle repair industry

Evaluating indoor exposure modeling alternatives for LCA: A case study in the vehicle repair industry

TitleEvaluating indoor exposure modeling alternatives for LCA: A case study in the vehicle repair industry
Publication TypeJournal Article
Year of Publication2009
AuthorsEvangelia Demou, Stefanie Hellweg, Michael P Wilson, S. Katharine Hammond, Thomas E McKone
JournalEnvironmental Science and Technology
Volume43
5804
Issue15
Pagination5804-5810
Date Published08/2009
KeywordsEnvironmental Chemistry, Exposure and Risk Group, exposure model, indoor environment department, life cycle assessment, pollutant fate and transport modeling, voc
Abstract

We evaluated three exposure models with data obtained from measurements amongworkers who use "aerosol" solvent products in the vehicle repair industry and with field experiments using these products to simulate the same exposure conditions. The three exposure models were the: 1) homogeneously-mixed-one-box model, 2) multi-zone model, and 3) eddy-diffusion model. Temporally differentiated real-time breathing zone 3 volatile organic compound (VOC) concentration measurements, integrated far-field area samples, and simulated experiments were used in estimating parameters, such as emission rates, diffusivity, and near-field dimensions. We assessed differences in model input requirements and their efficacy for predictive modeling. The One-box model was not able to resemble the temporal profile of exposure concentrations, but it performed well concerning time-weighted exposure over extended time periods. However, this model required an adjustment for spatial concentration gradients. Multi-zone models and diffusion-models may solve this problem. However, we found that the reliable use of both these models requires extensive field data to appropriately define pivotal parameters such as diffusivity or near-field dimensions. We conclude that it is difficult to apply thesemodels for predicting VOC exposures in the workplace. However, for comparativeexposure scenarios in life-cycle assessment they may be useful.

LBNL Report Number

LBNL-2404E

Short TitleEnviron. Sci. Technol.