Table 2.
Distribution of daily pollutant concentrations, temperature, and humidity during the study period (Sept. 2006 through June 2009)
| Pollutant | Days of data collection | 24-hour mean (± SD) | Percentiles
|
||||||
|---|---|---|---|---|---|---|---|---|---|
| Minimum | 5th | 25th | 50th | 75th | 95th | Maximum | |||
|
Ultrafine particles (p/cm3) |
990 | 5151 (2359) | 480 | 1954 | 3442 | 4843 | 6449 | 9575 | 14450 |
|
Accumulation mode particles (p/cm3) |
990 | 1054 (679) | 108 | 280 | 525 | 899 | 1399 | 2329 | 4444 |
| Fine particles (μg/m3) | 939 | 8.6 (5.9) | 0.1 | 1.9 | 4.4 | 7.4 | 11.1 | 20.3 | 43.0 |
|
Carbon monoxide (ppm) |
982 | 0.40 (0.16) | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.7 | 1.0 |
| Sulfur dioxide (ppb) | 1011 | 5.4 (7.7) | 1.0 | 1.2 | 2.0 | 3.3 | 5.1 | 19.4 | 50.0 |
| Ozone (ppb) | 1008 | 26.1 (10.2) | 1.5 | 11.5 | 18.8 | 25.2 | 33.0 | 43.6 | 64.7 |
| Black carbon (μg/m3) | 923 | 0.68 (0.40) | 0.05 | 0.20 | 0.37 | 0.61 | 0.90 | 1.40 | 2.44 |
| Temperature (°C) | 1034 | 9.8 (7.7) | −13.2 | −6.6 | 1.4 | 10.4 | 18.7 | 24.6 | 29.4 |
| Relative humidity (%) | 1033 | 64.1 (14.0) | 10.2 | 40.9 | 55.8 | 65.2 | 73.5 | 85.2 | 95.3 |
p/cm3: parts per cubic centimeter; μg/m3: micrograms per cubic meter; ppm: parts per million; ppb: parts per billion