Size-dependent PM_(10) indoor/outdoor/personal relationships for a wind-induced naturally ventilated airspace

摘要

We applied a simple size-dependent indoor air quality model associated with a compartmental lung model to characterize PM_(10) indoor―outdoor―personal exposure relationships for wind-induced naturally ventilated residences in Taiwan region. The natural ventilation rate was quantified by the opening effectiveness for sidewall opening (SP) and covered ridge with sidewall opening (CRSP) type homes. The predicted PM_(10) mass indoor/outdoor (I/O) ratios were 0.15―0.24 and 0.20―0.32, respectively, for SP and CRSP type homes. Results demonstrate that PM_(10) I/O ratios for a wind-induced naturally ventilated airspace depend strongly on the ambient PM size distributions, building openings design (e.g. height to length ratio of openings and roof slope), wind speed and wind angle of incidence. The predictions from our lung model agreed favorable with the experimental deposition profiles in extrathoracic (ET), bronchial―bronchiolar (BB), and alveolar―interstitial (AI) regions. Our results demonstrate that ET region has higher PM_(10) mass lung/indoor ratios (for north Taiwan region: 0.67―0.78; for central: 0.66―0.74) than that of BB (for north: 0.36―0.57; for central: 0.33―0.47) and AI regions (for north: 0.05―0.35; for central: 0.02―0.22). The present approach can be used in the future to appraise the significance of inter-subject lung morphology and breathing physiology variability for PM deposition and dose calculations.