Table 2. Range of 3-year average concentrations of ambient air pollutants in the 25 districts, 2006–2008.
| Air pollutant | Mean ± SD | Medianb | Interquartile rangea |
Min | Max |
| PM10 (µg/m3) | 124.2 ± 24.1 | 128 | 31 | 79 | 171 |
| SO2 (µg/m3) | 50.3 ± 16.8 | 50 | 21 | 20 | 80 |
| NO2 (µg/m3) | 36.7 ± 7.6 | 36 | 10 | 21 | 51 |
aRange from 25th to 75th percentile of district-specific concentrations.
bMedian range of deviation from 3-year mean within the 25 districts; min and max are ranges in the districts with the smallest and largest range of deviation from the districts’ mean.
PM10, particles with an aerodynamic diameter ≤10 µm; SO2, sulfur dioxide; NO2, nitrogen dioxides.