Commuters’ exposure to PM₂.₅ and CO₂ in metro carriages of Shanghai metro system

Abstract Air quality inside transportation carriages has become a public concern. A comprehensive measurement campaign was conducted to examine the commuters’ exposure to PM2.5 (dp ? 2.5 µm) and CO₂ in Shanghai metro system under different conditions. The PM2.5 and CO₂ concentrations inside all the measured metro lines were observed at 84 ± 42 µg/m3 and 1253.1 ± 449.1 ppm, respectively. The factors that determine the in-carriage PM2.5 and CO₂ concentrations were quantitatively investigated. The metro in-carriage PM2.5 concentrations were significantly affected by the ventilation systems, out-carriage PM2.5 concentrations and the passenger numbers. The largest in-carriage PM2.5 and CO₂ concentrations were observed at 132 µg/m3 and 1855.0 ppm inside the carriages equipped with the oldest ventilation systems. The average PM2.5 and CO₂ concentrations increased by 24.14% and 9.93% as the metro was driven from underground to overground. The average in-carriage PM2.5 concentrations increased by 17.19% and CO₂ concentration decreased by 16.97% as the metro was driven from urban to the suburban area. It was found that PM2.5 concentration is proportional to the on-board passenger number at a ratio of 0.4 µg/m3·passenger. A mass-balance model was developed to estimate the in-carriage PM2.5 concentration under different driving conditions.

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  • English

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  • Accession Number: 01608791
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jul 29 2016 1:57PM