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Air Quality in Indiana

Air Quality in Indiana > Air Quality 101 Air Quality 101

February 13, 2015: How Do You Rate a State’s Air Quality - Comparing Data

A person has challenged me, stating that I am inflating the quality of Indiana’s air. They claim that if I compare levels of the air in Indiana with other states, I will see that Indiana has poor air quality. There are several problems with this approach.

First, air quality is not a race between states. Instead, the goal is meeting the national ambient air quality standards (NAAQS).

U.S. EPA establishes these NAAQS to protect the public with an adequate margin of safety, including sensitive groups. All measured air in Indiana met the NAAQS for all six criteria air pollutants in 2009, and air quality has continued to improve since then.

Staying focused on meeting the NAAQS will help us keep jobs, and keep our environment and our economy healthy. If we are meeting the NAAQS, it isn’t wise to have additional restrictions that would help us achieve better air quality than another state if it means losing industry and jobs or risking a healthy economy and quality of life.

It is also difficult, if not impossible, to truly compare air quality between states. Some states monitor at many locations, others at very few. The purpose of monitoring is usually to find maximum concentrations, not average levels. So using a value from a county to represent either the entire county or counties nearby is a reach. For example, Douglas County, Colorado has an ozone monitor. It is located in the northern part of the county. The elevation of the county increases significantly from the location where the monitor is located. The level measured at the monitor does not represent the levels at other parts of the county due to the terrain.

It is possible to compare state monitoring networks. Indiana is ninth overall, comparing the number of samplers with the number of people living here. This means our state has a very good monitoring network given the number of people living here, and a system that is more extensive than most other states’.

To do the ranking, I reviewed U.S. EPA’s AIRDATA system to determine how many valid sites operated in 2013 in each state for five criteria air pollutants (PM-2.5 or fine particles; sulfur dioxide; nitrogen dioxide; ozone; and carbon monoxide). I divided the numbers of samplers by the 2013 state population and multiplied by 1,000,000 to determine how many samplers were operated per million people. (It should be noted that all PM-2.5 data for Illinois for 2013 was removed due to quality assurance issues. This artificially lowers the rating for Illinois for this time period.) For each pollutant, I ranked the states from first to 51st. I then summed the values for all five pollutants and ranked the total to see how each state did.

Monitors Per Million People and Ranking Based on 2013 Data
State PM-2.5 SO2 NOx Ozone CO Total Overall
AL 3.93(18) 0.83(45) 0.21(47) 4.76(24) 0.83(32) 166 39
AK 1.24(47) 1.36(27) 0.00(50) 2.72(43) 5.44(1) 168 42
AZ 2.90(26) 1.21(31) 1.06(27) 6.94(12) 2.72(6) 102 17
AR 2.28(31) 0.68(48) 0.68(33) 3.04(36) 0.34(43) 191 45
CA 14.69(1) 0.86(42) 2.63(11) 4.77(22) 1.83(16) 92 11
CO 3.93(19) 0.95(40) 1.71(16) 8.73(7) 1.90(14) 96 13
CT 2.07(36) 1.39(25) 1.39(20) 3.34(33) 1.95(13) 127 25
DE 1.45(43) 5.40(7) 3.24(8) 7.56(10) 2.16(10) 78 7
DC 0.62(50) 3.09(12) 4.64(7) 4.64(25) 4.64(4) 98 16
FL 4.97(11) 1.02(37) 0.46(40) 2.92(40) 0.51(39) 167 40
GA 5.17(8) 0.70(47) 0.30(42) 2.10(47) 0.30(46) 190 44
HI 2.90(27) 8.55(3) 1.42(19) 1.42(51) 2.14(11) 111 20
ID 1.45(44) 1.86(22) 0.62(34) 1.86(49) 1.86(15) 164 38
IL 0.00(51) 1.24(30) 0.54(35) 2.95(39) 0.23(48) 203 49
IN 6.62(5) 3.20(10) 1.07(26) 6.70(13) 0.91(28) 82 9
IA 4.55(12) 3.24(9) 1.29(25) 4.85(20) 0.97(24) 90 10
KS 2.28(32) 1.38(26) 1.38(21) 3.46(30) 0.69(36) 145 30
KY 5.17(9) 2.96(14) 1.37(22) 6.60(14) 0.68(37) 96 14
LA 3.10(23) 1.30(28) 2.16(13) 5.19(18) 0.22(49) 131 28
ME 2.07(37) 3.01(13) 2.26(12) 12.80(2) 2.26(9) 73 6
MD 3.52(21) 0.84(44) 0.51(37) 3.37(31) 0.84(30) 163 37
MA 3.52(22) 1.05(35) 1.79(14) 5.08(19) 1.05(23) 113 21
MI 6.41(6) 1.11(32) 0.51(38) 3.03(37) 0.81(33) 146 31
MN 4.34(13) 1.29(29) 0.92(28) 3.14(35) 1.11(21) 126 24
MS 1.66(42) 0.67(49) 0.33(41) 3.34(32) 0.33(44) 208 50
MO 3.10(24) 1.49(24) 0.83(31) 3.81(28) 0.50(40) 147 32
MT 2.90(28) 5.91(6) 8.87(3) 7.88(9) 1.97(12) 58 2
NE 1.45(45) 1.07(33) 0.00(51) 2.68(44) 1.07(22) 195 47
NV 2.28(33) 0.72(46) 1.43(18) 7.88(8) 3.58(5) 110 19
NH 1.86(39) 4.53(8) 0.76(32) 9.07(6) 2.27(8) 93 12
NJ 4.34(14) 1.01(38) 0.90(29) 1.91(48) 0.56(38) 167 40
NM 1.45(46) 2.40(16) 4.80(6) 12.47(3) 0.96(26) 97 15
NY 4.34(15) 0.97(39) 0.25(46) 1.58(50) 0.36(42) 192 46
NC 7.24(4) 0.91(41) 0.20(48) 4.77(23) 0.30(45) 161 36
ND 1.86(40) 22.12(1) 12.44(2) 12.44(4) 1.38(20) 67 4
OH 9.10(2) 2.85(15) 0.26(44) 4.41(27) 0.86(29) 117 22
OK 2.07(38) 2.08(19) 1.30(24) 6.49(15) 0.78(34) 130 27
OR 2.90(29) 0.25(51) 0.25(45) 2.54(45) 0.25(47) 217 51
PA 8.48(3) 2.35(17) 1.72(15) 4.54(26) 1.41(19) 80 8
RI 1.24(48) 1.90(21) 2.85(10) 2.85(42) 0.95(27) 148 33
SC 2.28(34) 1.68(23) 0.84(30) 4.82(21) 0.21(50) 158 35
SD 2.28(35) 5.92(5) 5.92(4) 7.10(11) 2.37(7) 62 3
TN 5.79(7) 2.16(18) 0.46(39) 3.69(29) 0.77(35) 128 26
TX 5.17(10) 1.06(34) 1.59(17) 2.91(41) 0.83(31) 133 29
UT 3.10(25) 2.07(20) 5.17(5) 9.31(5) 1.72(17) 72 5
VT 1.03(49) 3.19(11) 3.19(9) 3.19(34) 4.79(3) 106 18
VA 1.86(41) 0.85(43) 1.33(23) 3.03(38) 0.97(25) 170 43
WA 3.93(20) 0.43(50) 0.29(43) 2.15(46) 0.43(41) 200 48
WV 2.90(30) 8.09(4) 0.00(49) 5.39(17) 1.62(18) 118 23
WI 4.14(17) 1.04(36) 0.52(36) 5.40(16) 0.17(51) 156 34
WY 4.34(16) 12.01(2) 41.19(1) 49.77(1) 5.15(2) 22 1

Comments can be sent to me at kbaugues@idem.in.gov.

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