Table 2 Distribution of hourly pollutant concentrations and weather characteristics (lag hour 0 of control periods) by period
| Â | Percentile | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Pollutant | N | Mean | SD | IQR | Minimum | 5th | 25th | 50th | 75th | 95th | Maximum |
PM2.5 (μg/m3) | |||||||||||
 All years (2005–2016) | 2900 | 8.32 | 7.17 | 7.59 | −7.85 | 0.19 | 3.63 | 6.83 | 11.22 | 21.86 | 76.15 |
 Before (2005–2007) | 788 | 10.37 | 8.74 | 8.40 | −3.31 | 0.86 | 4.84 | 8.22 | 13.24 | 26.79 | 76.15 |
 During (2008–2013) | 1134 | 8.31 | 6.83 | 7.60 | −3.94 | 0.25 | 3.80 | 6.75 | 11.40 | 21.87 | 47.15 |
 After (2014–2016) | 978 | 6.67 | 5.55 | 6.60 | −7.85 | −0.36 | 2.76 | 5.69 | 9.35 | 16.80 | 48.65 |
AMP (particles/cm3) | |||||||||||
 All years (2005–2016) | 2680 | 781 | 658 | 698 | 10 | 138 | 327 | 610 | 1025 | 1978 | 6578 |
 Before (2005–2007) | 566 | 1139 | 908 | 980 | 62 | 179 | 481 | 940 | 1461 | 2960 | 6015 |
 During (2008–2013) | 1156 | 739 | 596 | 672 | 32 | 140 | 317 | 586 | 988 | 1797 | 6578 |
 After (2014–2016) | 958 | 620 | 440 | 554 | 10 | 122 | 282 | 527 | 836 | 1469 | 2926 |
UFP (particles/cm3) | |||||||||||
 All years (2005–2016) | 2680 | 4286 | 3775 | 3702 | 70 | 738 | 1777 | 3232 | 5479 | 11,708 | 41,965 |
 Before (2005–2007) | 566 | 6916 | 5247 | 6046 | 325 | 1300 | 3235 | 5405 | 9281 | 16,720 | 41,965 |
 During (2008–2013) | 1156 | 3492 | 2832 | 3141 | 191 | 585 | 1466 | 2798 | 4606 | 8642 | 20,826 |
 After (2014–2016) | 958 | 3690 | 2958 | 2951 | 70 | 774 | 1728 | 2923 | 4679 | 9212 | 31,417 |
UFP(11-50 nm)(particles/cm3) | |||||||||||
 All years (2005–2016) | 2680 | 2963 | 2906 | 2755 | 30 | 392 | 1087 | 2106 | 3842 | 8588 | 32,747 |
 Before (2005–2007) | 566 | 4839 | 3958 | 4327 | 158 | 845 | 2015 | 3762 | 6342 | 12,708 | 32,747 |
 During (2008–2013) | 1156 | 2385 | 2148 | 2260 | 117 | 327 | 886 | 1770 | 3146 | 6515 | 17,182 |
 After (2014–2016) | 958 | 2552 | 2485 | 2182 | 30 | 419 | 1035 | 1805 | 3217 | 7202 | 29,559 |
UFP(50-100 nm)(particles/cm3) | |||||||||||
 All years (2005–2016) | 2680 | 1323 | 1242 | 1161 | 14 | 199 | 532 | 979 | 1693 | 3628 | 11,198 |
 Before (2005–2007) | 566 | 2077 | 1824 | 1701 | 73 | 316 | 878 | 1568 | 2579 | 5940 | 11,198 |
 During (2008–2013) | 1156 | 1107 | 972 | 963 | 48 | 174 | 470 | 842 | 1433 | 2943 | 8650 |
 After (2014–2016) | 958 | 1138 | 886 | 1016 | 14 | 185 | 504 | 905 | 1521 | 2851 | 6309 |
BC (μg/m3) | |||||||||||
 All years (2005–2016) | 3039 | 0.49 | 0.47 | 0.44 | −0.07 | 0.06 | 0.19 | 0.36 | 0.63 | 1.36 | 5.31 |
 Before (2005–2007) | 783 | 0.69 | 0.60 | 0.63 | −0.02 | 0.09 | 0.28 | 0.53 | 0.91 | 1.84 | 5.31 |
 During (2008–2013) | 1226 | 0.50 | 0.44 | 0.46 | −0.07 | 0.08 | 0.21 | 0.37 | 0.66 | 1.34 | 3.74 |
 After (2014–2016) | 1030 | 0.33 | 0.28 | 0.30 | −0.04 | 0.04 | 0.14 | 0.25 | 0.44 | 0.92 | 2.13 |
SO2 (ppb) | |||||||||||
 All years (2005–2016) | 3006 | 1.98 | 3.10 | 1.77 | −0.09 | 0.09 | 0.32 | 1.00 | 2.09 | 7.00 | 68.00 |
 Before (2005–2007) | 822 | 4.11 | 4.41 | 3.00 | 0.00 | 1.00 | 2.00 | 3.00 | 5.00 | 11.00 | 68.00 |
 During (2008–2013) | 1179 | 1.54 | 2.20 | 1.70 | −0.09 | 0.01 | 0.30 | 0.97 | 2.00 | 5.00 | 21.00 |
 After (2014–2016) | 1005 | 0.76 | 1.33 | 0.54 | 0.00 | 0.09 | 0.20 | 0.37 | 0.74 | 2.61 | 16.35 |
O3 (ppb) | |||||||||||
 All years (2005–2016) | 2992 | 26.6 | 14.1 | 18.0 | 0.0 | 2.0 | 17.0 | 26.0 | 35.0 | 50.0 | 83.0 |
 Before (2005–2007) | 828 | 21.9 | 14.6 | 21.0 | 0.0 | 1.0 | 10.0 | 21.0 | 31.0 | 49.0 | 77.0 |
 During (2008–2013) | 1162 | 28.1 | 14.0 | 16.0 | 0.0 | 4.0 | 20.0 | 28.0 | 36.0 | 51.0 | 83.0 |
 After (2014–2016) | 1002 | 28.9 | 12.9 | 17.0 | 0.0 | 6.0 | 20.0 | 29.0 | 37.0 | 50.0 | 72.0 |
CO (ppm) | |||||||||||
 All years (2005–2016) | 2939 | 0.30 | 0.20 | 0.23 | −0.01 | 0.12 | 0.17 | 0.22 | 0.40 | 0.65 | 2.50 |
 Before (2005–2007) | 814 | 0.48 | 0.22 | 0.30 | 0.10 | 0.20 | 0.30 | 0.40 | 0.60 | 0.80 | 2.50 |
 During (2008–2013) | 1124 | 0.26 | 0.16 | 0.14 | 0.00 | 0.12 | 0.16 | 0.20 | 0.30 | 0.60 | 1.10 |
 After (2014–2016) | 1001 | 0.20 | 0.07 | 0.06 | −0.01 | 0.12 | 0.16 | 0.19 | 0.22 | 0.33 | 1.02 |
Temperature (°F) | |||||||||||
 All years (2005–2016) | 3065 | 50.7 | 20.3 | 32.1 | −5.0 | 19.2 | 34.8 | 50.0 | 66.9 | 83.7 | 96.4 |
 Before (2005–2007) | 839 | 48.4 | 18.9 | 30.5 | 1.4 | 20.2 | 33.2 | 46.9 | 63.7 | 78.7 | 95.9 |
 During (2008–2013) | 1196 | 49.5 | 20.2 | 32.1 | 4.8 | 20.1 | 33.4 | 46.6 | 65.5 | 84.9 | 96.4 |
 After (2014–2016) | 1030 | 53.9 | 21.0 | 32.9 | −5.0 | 17.5 | 38.0 | 55.3 | 70.9 | 84.3 | 92.6 |
Relative Humidity | |||||||||||
 All years (2005–2016) | 3064 | 64.5 | 19.9 | 32.0 | 7.1 | 30.0 | 49.0 | 66.3 | 81.0 | 93.0 | 102.0 |
 Before (2005–2007) | 838 | 69.6 | 19.0 | 28.0 | 7.1 | 35.0 | 58.0 | 73.0 | 86.0 | 93.4 | 98.2 |
 During (2008–2013) | 1196 | 64.1 | 19.5 | 31.0 | 12.0 | 30.0 | 49.0 | 66.0 | 80.0 | 93.0 | 102.0 |
 After (2014–2016) | 1030 | 60.9 | 20.1 | 32.0 | 15.0 | 29.0 | 45.0 | 61.0 | 77.0 | 93.0 | 99.0 |