Table 2.
Daily averages of exposure variables inside the taxicab.
| Perioda |
Percentileb |
|||||||
|---|---|---|---|---|---|---|---|---|
| Variable | Before | During | After | 25 | 50 | 75 | 95 | IQR |
| PM2.5, real time (μg/m3) | 95.4 ± 58.6 | 39.5 ± 25.2 | 64.0 ± 80.3 | 22.7 | 44.6 | 84.8 | 207.2 | 62.1 |
| PM2.5, mass (μg/m3) | 105.5 ± 44.1 | 45.2 ± 27.0 | 80.4 ± 72.5 | 34.6 | 56.6 | 104.1 | 182.5 | 69.5 |
| CO (ppm) | 3.6 ± 1.4 | 2.8 ± 1.0 | 2.7 ± 0.7 | 2.2 | 2.6 | 3.7 | 5.0 | 1.5 |
| NO2 (ppb) | 36.4 ± 12.3 | 30.3 ± 12.2 | 37.1 ± 17.0 | 24.2 | 32.8 | 45.3 | 61.0 | 21.1 |
| NO (ppb) | 176.1 ± 84.8 | 156.0 ± 77.2 | 268.0 ± 55.5 | 125.6 | 181.5 | 274.8 | 362.2 | 149.2 |
| Temperature (°C) | 30.0 ± 4.4 | 28.8 ± 2.0 | 25.0 ± 2.2 | 24.9 | 28.4 | 30.3 | 33.5 | 5.4 |
| RH (%) | 38.8 ± 9.5 | 41.7 ± 6.6 | 24.8 ± 5.8 | 28.8 | 35.2 | 40.9 | 51.2 | 12.1 |
a
Before, during, and after the Beijing 2008 Olympic Games indicates the periods of 26 May to 19 June, 11 August to 5 September, and 27 October to 14 November, respectively; concentrations are presented as arithmetic mean ± SD for the three time periods.
b
Percentiles were calculated and presented after combining exposure data from all three time periods.