TY - JOUR
T1 - Transport of particulate and gaseous pollutants in the vicinity of a human body
AU - Rim, Donghyun
AU - Novoselac, Atila
N1 - Funding Information:
The research is partially supported by the National Science Foundation Integrative Graduate Education and Research Traineeship (IGERT) grant DCE-0549428, Indoor Environmental Science and Engineering, at The University of Texas at Austin. The authors are grateful for careful review of the manuscript by Catherine Mukai and Jeffery Siegel.
Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2009/9
Y1 - 2009/9
N2 - A uniform pollutant concentration in indoor environments can be an inappropriate representation of breathing concentration. This is especially true when local airflow in the vicinity of an occupant is dominant in transporting pollutants. The present study investigates the airflow in the vicinity of a human body, effects of respiration on breathing concentration of particulate and gaseous pollutants, and inhalation exposure in relation to source position and overall airflow patterns. It is based on experiments with a human simulator in a full-scale environmental chamber. Airflow and pollutant concentrations in the vicinity of a thermal manikin are monitored, while varying parameters including breathing, arm/hand movements, and ventilation system. Results show that breathing of a sedentary manikin has a measurable influence on the airflow in breathing zone, whereas it has very small impacts on occupant thermal plume. Also, localized hand motions have insignificant effects on the thermal plume. The results indicate that overall airflow pattern affect the inhaled particle concentrations. With highly mixed airflow in the space, relatively uniform concentration patterns occur in the occupant vicinity. However, with stratified airflow patterns, non-uniform concentration patterns are observed due to the occupant thermal plume. With a particle source at floor level and in near proximity to an occupant, inhaled particle concentrations are up to four times higher than the ambient concentrations. This finding implies that occupant thermal plume may play a significant role in transporting pollutants from floor level to the breathing zone. The non-uniform concentration observed with stratified flow also suggests caution in estimating inhalation exposure using a "well-mixed" mass balance model.
AB - A uniform pollutant concentration in indoor environments can be an inappropriate representation of breathing concentration. This is especially true when local airflow in the vicinity of an occupant is dominant in transporting pollutants. The present study investigates the airflow in the vicinity of a human body, effects of respiration on breathing concentration of particulate and gaseous pollutants, and inhalation exposure in relation to source position and overall airflow patterns. It is based on experiments with a human simulator in a full-scale environmental chamber. Airflow and pollutant concentrations in the vicinity of a thermal manikin are monitored, while varying parameters including breathing, arm/hand movements, and ventilation system. Results show that breathing of a sedentary manikin has a measurable influence on the airflow in breathing zone, whereas it has very small impacts on occupant thermal plume. Also, localized hand motions have insignificant effects on the thermal plume. The results indicate that overall airflow pattern affect the inhaled particle concentrations. With highly mixed airflow in the space, relatively uniform concentration patterns occur in the occupant vicinity. However, with stratified airflow patterns, non-uniform concentration patterns are observed due to the occupant thermal plume. With a particle source at floor level and in near proximity to an occupant, inhaled particle concentrations are up to four times higher than the ambient concentrations. This finding implies that occupant thermal plume may play a significant role in transporting pollutants from floor level to the breathing zone. The non-uniform concentration observed with stratified flow also suggests caution in estimating inhalation exposure using a "well-mixed" mass balance model.
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U2 - 10.1016/j.buildenv.2008.12.009
DO - 10.1016/j.buildenv.2008.12.009
M3 - Article
AN - SCOPUS:64049093503
SN - 0360-1323
VL - 44
SP - 1840
EP - 1849
JO - Building and Environment
JF - Building and Environment
IS - 9
ER -