Table 1.
Three-day moving averagea ambient air pollutant concentrations, temperature, and humidity
| Pollutant | Mean (SD) | Range | IQRb | 25th percentiles | 75th percentiles |
|---|---|---|---|---|---|
| 1-hr max CO (ppm) | 0.36 (0.26) | 0.06–4.47 | 0.22 | 0.20 | 0.42 |
| 1-hr max NO2 (ppb) | 9.22 (9.62) | 0.07–73.88 | 9.33 | 2.70 | 12.03 |
| 8-hr max O3 (ppb) | 42.1 (12.6) | 5.4–106.1 | 18.5 | 32.4 | 50.9 |
| 1-hr max SO2 (ppb) | 6.12 (5.18) | −0.06–112.80 | 5.60 | 2.52 | 8.12 |
| 24-hr avg. PM10 (μg/m3) | 22.5 (8.9) | 5.5–198.1 | 11.5 | 16.0 | 27.6 |
| 24-hr avg. PM2.5 (μg/m3) | 13.2 (5.7) | 2.4–86.4 | 6.9 | 9.2 | 16.1 |
| 24-hr avg. EC (μg/m3) | 0.66 (0.46) | 0.03–7.79 | 0.48 | 0.35 | 0.83 |
| 24-hr avg. OC (μg/m3) | 2.52 (1.25) | 0.26–39.87 | 1.45 | 1.65 | 3.09 |
| 24-hr avg. NH4 + (μg/m3) | 1.17 (0.64) | 0.10–5.84 | 0.73 | 0.72 | 1.45 |
| 24-hr avg. NO3 –(μg/m3) | 0.51 (0.45) | 0.02–5.70 | 0.51 | 0.19 | 0.70 |
| 24-hr avg. SO4 2− (μg/m3) | 3.95 (2.30) | 0.46–22.55 | 2.72 | 2.28 | 5.00 |
| Relative humidity (%) | 60.2 (10.7) | 21.4–93.2 | 14.8 | 52.8 | 67.6 |
| Temperature (°C) | 294.6 (8.2) | 266.4–313.3 | 13.6 | 288.1 | 301.7 |
aThe 3-day moving average was calculated for 742 ZIP code areas in Georgia during 2002–2008 (n = 1897294)
bIQR was calculated as the difference between the 25th and 75th percentile of the 3-day moving average