Skip to main content
Article
The Impact of Freeway Traffic Conditions on in-Vehicle Exposure to Ultrafine Particulate Matter
Civil and Environmental Engineering Faculty Publications and Presentations
  • Miguel A. Figliozzi, Portland State University
  • Alexander Y. Bigazzi, Portland State University
Document Type
Pre-Print
Publication Date
12-1-2012
Subjects
  • Greenhouse gas mitigation,
  • Air -- Pollution -- Prevention,
  • Traffic congestion -- Environmental aspects,
  • Air quality management,
  • Transportation -- Management -- Environmental aspects
Abstract

There is evidence of adverse health impacts from human exposure to traffic-related ultrafine particulate matter pollution. As more commuters are spending a significant portion of their daily routine inside vehicles, it is increasingly relevant to study exposure levels to harmful pollutants inside the vehicle microenvironment. This study is one of the first research efforts to combine detailed freeway traffic data (at 20 s intervals) and in-vehicle ultrafine particulate (UFP) exposure data under varying vehicle ventilation conditions. Results show that due to negative correlation between traffic speed and density, traffic states have a small but significant impact on in-vehicle UFP concentrations, highest in high traffic flow-high speed conditions or in high traffic density-low speed conditions. Vehicle cabin barrier effects are the primary determinant of in-vehicle exposure concentrations, providing 15% protection with the windows down, 47% protection with the windows up and the vent open, and 83-90% protection with the windows up and the vent closed (more with the air conditioning on). Unique results from this study include the dominance of ventilation over traffic effects on UFP and the non-linear relationships between traffic variables and UFP concentrations. The results of this research have important implications for exposure modeling and potential exposure mitigation strategies.

Persistent Identifier
http://archives.pdx.edu/ds/psu/8842
Citation Information
Bigazzi, A., Figliozzi, M., Impacts of freeway traffic conditions on in-vehicle exposure to ultrafine particulate matter, Atmospheric Environment, Volume 60, pp 495-503, 2012.