Cleanest Air by State

In plain terms: Hawaii has the cleanest measured air of the 53 states and territories with an EPA air monitor, and California the worst.

1. 1Hawaii3 monitored countiesGood80

   • Maui County, HIGood · AQI90 32 · ZIP 9670884
   • Honolulu County, HIGood · AQI90 39 · ZIP 9670181
   • Hawaii County, HIModerate · AQI90 53 · ZIP 9670474
2. 2Puerto Rico8 monitored countiesGood77

   • Mayagüez Municipio, PRGood · AQI90 21 · ZIP 0068090
   • Caguas Municipio, PRGood · AQI90 37 · ZIP 0072582
   • Guayama Municipio, PRGood · AQI90 37 · ZIP 0078482
   • Ponce Municipio, PRGood · AQI90 42 · ZIP 0071579
   • Bayamón Municipio, PRModerate · AQI90 55 · ZIP 0095673
   • Fajardo Municipio, PRModerate · AQI90 57 · ZIP 0073872
   • Guaynabo Municipio, PRModerate · AQI90 57 · ZIP 0093472
   • Cataño Municipio, PRModerate · AQI90 62 · ZIP 0096269
3. 3Virgin Islands1 monitored countyModerate75

   • St. John Island, VIModerate · AQI90 51 · ZIP 0083075
4. 4Montana23 monitored countiesModerate75

   • Rosebud County, MTGood · AQI90 27 · ZIP 5901287
   • Teton County, MTGood · AQI90 26 · ZIP 5941987
   • Gallatin County, MTGood · AQI90 26 · ZIP 5971487
   • Beaverhead County, MTGood · AQI90 29 · ZIP 5972486
   • Powell County, MTGood · AQI90 33 · ZIP 5971384
   • Lake County, MTGood · AQI90 33 · ZIP 5982484
   • Hill County, MTGood · AQI90 40 · ZIP 5950180
   • Glacier County, MTGood · AQI90 44 · ZIP 5941178
   • Phillips County, MTGood · AQI90 47 · ZIP 5926177
   • Fergus County, MTGood · AQI90 49 · ZIP 5903276
   • Dawson County, MTGood · AQI90 49 · ZIP 5925976
   • Custer County, MTModerate · AQI90 53 · ZIP 5930174
   • Yellowstone County, MTModerate · AQI90 54 · ZIP 5900273
   • Roosevelt County, MTModerate · AQI90 54 · ZIP 5920173
   • Sheridan County, MTModerate · AQI90 54 · ZIP 5921173
   • Silver Bow County, MTModerate · AQI90 54 · ZIP 5970173
   • Sanders County, MTModerate · AQI90 55 · ZIP 5983173
   • Missoula County, MTModerate · AQI90 56 · ZIP 5980172
   • Richland County, MTModerate · AQI90 59 · ZIP 5921771
   • Ravalli County, MTModerate · AQI90 59 · ZIP 5982771
   • Flathead County, MTModerate · AQI90 62 · ZIP 5990169
   • Lewis and Clark County, MTModerate · AQI90 65 · ZIP 5941068
   • Lincoln County, MTModerate · AQI90 67 · ZIP 5991767
5. 5New Hampshire7 monitored countiesModerate73

   • Merrimack County, NHGood · AQI90 46 · ZIP 0304677
   • Belknap County, NHModerate · AQI90 51 · ZIP 0321875
   • Hillsborough County, NHModerate · AQI90 55 · ZIP 0303173
   • Rockingham County, NHModerate · AQI90 54 · ZIP 0303273
   • Grafton County, NHModerate · AQI90 54 · ZIP 0321573
   • Cheshire County, NHModerate · AQI90 57 · ZIP 0343172
   • Coos County, NHModerate · AQI90 61 · ZIP 0357070
6. 6Maine11 monitored countiesModerate73

   • York County, MEGood · AQI90 45 · ZIP 0390178
   • Knox County, MEGood · AQI90 44 · ZIP 0454778
   • Sagadahoc County, MEGood · AQI90 47 · ZIP 0400877
   • Hancock County, MEGood · AQI90 49 · ZIP 0440876
   • Washington County, MEGood · AQI90 49 · ZIP 0441376
   • Androscoggin County, MEModerate · AQI90 54 · ZIP 0421073
   • Kennebec County, MEModerate · AQI90 55 · ZIP 0425973
   • Aroostook County, MEModerate · AQI90 57 · ZIP 0445172
   • Penobscot County, MEModerate · AQI90 58 · ZIP 0440171
   • Oxford County, MEModerate · AQI90 60 · ZIP 0357970
   • Cumberland County, MEModerate · AQI90 62 · ZIP 0400369
7. 7Vermont4 monitored countiesModerate73

   • Windham County, VTGood · AQI90 48 · ZIP 0510176
   • Bennington County, VTModerate · AQI90 54 · ZIP 0515273
   • Chittenden County, VTModerate · AQI90 55 · ZIP 0540173
   • Rutland County, VTModerate · AQI90 58 · ZIP 0570171
8. 8Virginia28 monitored countiesModerate73

   • Carroll County, VAGood · AQI90 16 · ZIP 2431292
   • Fauquier County, VAGood · AQI90 44 · ZIP 2011578
   • Caroline County, VAGood · AQI90 45 · ZIP 2242778
   • Prince Edward County, VAGood · AQI90 44 · ZIP 2390978
   • Prince William County, VAGood · AQI90 46 · ZIP 2010977
   • Stafford County, VAGood · AQI90 46 · ZIP 2213477
   • Hanover County, VAGood · AQI90 46 · ZIP 2300577
   • Suffolk city, VAGood · AQI90 47 · ZIP 2343277
   • Giles County, VAGood · AQI90 47 · ZIP 2408677
   • Rockbridge County, VAGood · AQI90 46 · ZIP 2441577
   • Wythe County, VAGood · AQI90 48 · ZIP 2431376
   • Charles City County, VAModerate · AQI90 51 · ZIP 2303075
   • Norfolk city, VAModerate · AQI90 53 · ZIP 2350274
   • Hampton city, VAModerate · AQI90 53 · ZIP 2365174
   • Lynchburg city, VAModerate · AQI90 53 · ZIP 2450274
   • Arlington County, VAModerate · AQI90 54 · ZIP 2220173
   • Henrico County, VAModerate · AQI90 55 · ZIP 2306073
   • Chesterfield County, VAModerate · AQI90 55 · ZIP 2311273
   • Richmond city, VAModerate · AQI90 54 · ZIP 2317373
   • Virginia Beach city, VAModerate · AQI90 55 · ZIP 2345173
   • Roanoke County, VAModerate · AQI90 55 · ZIP 2401473
   • Bristol city, VAModerate · AQI90 55 · ZIP 2420173
   • Rockingham County, VAModerate · AQI90 56 · ZIP 2280172
   • Albemarle County, VAModerate · AQI90 56 · ZIP 2290172
   • Loudoun County, VAModerate · AQI90 58 · ZIP 2010571
   • Fairfax County, VAModerate · AQI90 59 · ZIP 2012071
   • Frederick County, VAModerate · AQI90 58 · ZIP 2260271
   • Madison County, VAModerate · AQI90 58 · ZIP 2270971
9. 9Wyoming17 monitored countiesModerate73

   • Uinta County, WYGood · AQI90 19 · ZIP 8293391
   • Washakie County, WYGood · AQI90 26 · ZIP 8240187
   • Lincoln County, WYGood · AQI90 26 · ZIP 8310187
   • Park County, WYGood · AQI90 28 · ZIP 8219086
   • Carbon County, WYGood · AQI90 33 · ZIP 8230184
   • Platte County, WYGood · AQI90 47 · ZIP 8220177
   • Converse County, WYGood · AQI90 49 · ZIP 8222476
   • Johnson County, WYGood · AQI90 49 · ZIP 8263976
   • Sheridan County, WYModerate · AQI90 51 · ZIP 8280175
   • Natrona County, WYModerate · AQI90 54 · ZIP 8260173
   • Teton County, WYModerate · AQI90 54 · ZIP 8300173
   • Campbell County, WYModerate · AQI90 62 · ZIP 8271669
   • Laramie County, WYModerate · AQI90 64 · ZIP 8200168
   • Fremont County, WYModerate · AQI90 64 · ZIP 8231068
   • Sweetwater County, WYModerate · AQI90 64 · ZIP 8232268
   • Sublette County, WYModerate · AQI90 64 · ZIP 8292268
   • Albany County, WYModerate · AQI90 77 · ZIP 8205162
10. 10Massachusetts13 monitored countiesModerate72

    • Dukes County, MAGood · AQI90 45 · ZIP 0253578
    • Barnstable County, MAGood · AQI90 46 · ZIP 0253277
    • Hampshire County, MAModerate · AQI90 54 · ZIP 0100273
    • Norfolk County, MAModerate · AQI90 55 · ZIP 0201973
    • Plymouth County, MAModerate · AQI90 54 · ZIP 0204373
    • Worcester County, MAModerate · AQI90 56 · ZIP 0100572
    • Middlesex County, MAModerate · AQI90 56 · ZIP 0143172
    • Essex County, MAModerate · AQI90 56 · ZIP 0181072
    • Bristol County, MAModerate · AQI90 56 · ZIP 0204872
    • Berkshire County, MAModerate · AQI90 59 · ZIP 0102971
    • Franklin County, MAModerate · AQI90 59 · ZIP 0105471
    • Hampden County, MAModerate · AQI90 61 · ZIP 0100170
    • Suffolk County, MAModerate · AQI90 60 · ZIP 0210870
11. 11Rhode Island3 monitored countiesModerate72

    • Kent County, RIGood · AQI90 46 · ZIP 0281677
    • Washington County, RIModerate · AQI90 56 · ZIP 0280472
    • Providence County, RIModerate · AQI90 59 · ZIP 0280271
12. 12West Virginia13 monitored countiesModerate72

    • Tucker County, WVGood · AQI90 47 · ZIP 2626077
    • Greenbrier County, WVGood · AQI90 49 · ZIP 2490176
    • Kanawha County, WVModerate · AQI90 55 · ZIP 2500373
    • Berkeley County, WVModerate · AQI90 54 · ZIP 2540173
    • Wood County, WVModerate · AQI90 54 · ZIP 2610173
    • Harrison County, WVModerate · AQI90 55 · ZIP 2630173
    • Ohio County, WVModerate · AQI90 56 · ZIP 2600372
    • Brooke County, WVModerate · AQI90 57 · ZIP 2603072
    • Marion County, WVModerate · AQI90 56 · ZIP 2655472
    • Cabell County, WVModerate · AQI90 58 · ZIP 2550471
    • Monongalia County, WVModerate · AQI90 58 · ZIP 2650171
    • Marshall County, WVModerate · AQI90 63 · ZIP 2603169
    • Hancock County, WVModerate · AQI90 64 · ZIP 2603468
13. 13Florida38 monitored countiesModerate72

    • Putnam County, FLGood · AQI90 43 · ZIP 3211279
    • Flagler County, FLGood · AQI90 45 · ZIP 3211078
    • Liberty County, FLGood · AQI90 44 · ZIP 3232178
    • Lake County, FLGood · AQI90 47 · ZIP 3210277
    • Polk County, FLGood · AQI90 46 · ZIP 3380177
    • Highlands County, FLGood · AQI90 47 · ZIP 3382577
    • St. Lucie County, FLGood · AQI90 46 · ZIP 3494577
    • Okaloosa County, FLGood · AQI90 48 · ZIP 3253176
    • Indian River County, FLGood · AQI90 48 · ZIP 3294876
    • Pasco County, FLGood · AQI90 49 · ZIP 3352376
    • Alachua County, FLModerate · AQI90 51 · ZIP 3260175
    • Brevard County, FLGood · AQI90 50 · ZIP 3275475
    • Manatee County, FLGood · AQI90 50 · ZIP 3420175
    • Volusia County, FLModerate · AQI90 53 · ZIP 3211474
    • Osceola County, FLModerate · AQI90 53 · ZIP 3384874
    • Baker County, FLModerate · AQI90 55 · ZIP 3204073
    • Wakulla County, FLModerate · AQI90 54 · ZIP 3232773
    • Seminole County, FLModerate · AQI90 54 · ZIP 3270173
    • Martin County, FLModerate · AQI90 55 · ZIP 3343873
    • Collier County, FLModerate · AQI90 55 · ZIP 3410173
    • Citrus County, FLModerate · AQI90 55 · ZIP 3442873
    • Hamilton County, FLModerate · AQI90 57 · ZIP 3205272
    • Marion County, FLModerate · AQI90 57 · ZIP 3211372
    • Bay County, FLModerate · AQI90 56 · ZIP 3240172
    • Escambia County, FLModerate · AQI90 57 · ZIP 3250172
    • Palm Beach County, FLModerate · AQI90 57 · ZIP 3340172
    • Pinellas County, FLModerate · AQI90 57 · ZIP 3370172
    • Lee County, FLModerate · AQI90 56 · ZIP 3390172
    • Columbia County, FLModerate · AQI90 59 · ZIP 3202471
    • Holmes County, FLModerate · AQI90 58 · ZIP 3242571
    • Santa Rosa County, FLModerate · AQI90 58 · ZIP 3253071
    • Orange County, FLModerate · AQI90 58 · ZIP 3270371
    • Broward County, FLModerate · AQI90 58 · ZIP 3300471
    • Sarasota County, FLModerate · AQI90 58 · ZIP 3422371
    • Leon County, FLModerate · AQI90 60 · ZIP 3230170
    • Miami-Dade County, FLModerate · AQI90 61 · ZIP 3301070
    • Duval County, FLModerate · AQI90 62 · ZIP 3220269
    • Hillsborough County, FLModerate · AQI90 63 · ZIP 3350369
14. 14Idaho19 monitored countiesModerate72

    • Custer County, IDGood · AQI90 31 · ZIP 8322685
    • Blaine County, IDGood · AQI90 36 · ZIP 8331382
    • Franklin County, IDGood · AQI90 39 · ZIP 8322881
    • Bonneville County, IDGood · AQI90 43 · ZIP 8312079
    • Twin Falls County, IDGood · AQI90 47 · ZIP 8330177
    • Butte County, IDGood · AQI90 50 · ZIP 8321375
    • Bannock County, IDModerate · AQI90 52 · ZIP 8320174
    • Latah County, IDModerate · AQI90 57 · ZIP 8353772
    • Boise County, IDModerate · AQI90 58 · ZIP 8360271
    • Canyon County, IDModerate · AQI90 58 · ZIP 8360571
    • Kootenai County, IDModerate · AQI90 58 · ZIP 8380171
    • Valley County, IDModerate · AQI90 60 · ZIP 8361170
    • Ada County, IDModerate · AQI90 61 · ZIP 8361670
    • Lemhi County, IDModerate · AQI90 63 · ZIP 8325369
    • Nez Perce County, IDModerate · AQI90 63 · ZIP 8350169
    • Idaho County, IDModerate · AQI90 62 · ZIP 8352269
    • Shoshone County, IDModerate · AQI90 66 · ZIP 8380267
    • Bonner County, IDModerate · AQI90 66 · ZIP 8380367
    • Benewah County, IDModerate · AQI90 66 · ZIP 8382467
15. 15Alaska8 monitored countiesModerate72

    • Kenai Peninsula Borough, AKGood · AQI90 16 · ZIP 9955692
    • Aleutians East Borough, AKGood · AQI90 21 · ZIP 9955390
    • North Slope Borough, AKGood · AQI90 23 · ZIP 9951989
    • Denali Borough, AKGood · AQI90 43 · ZIP 9970479
    • Matanuska-Susitna Borough, AKGood · AQI90 47 · ZIP 9962377
    • Juneau City and Borough, AKModerate · AQI90 58 · ZIP 9980171
    • Anchorage Municipality, AKModerate · AQI90 61 · ZIP 9950170
    • Fairbanks North Star Borough, AKModerate · AQI90 85 · ZIP 9970258
16. 16New Jersey15 monitored countiesModerate71

    • Monmouth County, NJGood · AQI90 50 · ZIP 0770175
    • Atlantic County, NJModerate · AQI90 54 · ZIP 0803773
    • Middlesex County, NJModerate · AQI90 57 · ZIP 0700172
    • Hudson County, NJModerate · AQI90 59 · ZIP 0700271
    • Morris County, NJModerate · AQI90 59 · ZIP 0700571
    • Ocean County, NJModerate · AQI90 58 · ZIP 0800571
    • Gloucester County, NJModerate · AQI90 58 · ZIP 0801471
    • Cumberland County, NJModerate · AQI90 59 · ZIP 0830271
    • Bergen County, NJModerate · AQI90 61 · ZIP 0701070
    • Passaic County, NJModerate · AQI90 61 · ZIP 0701170
    • Union County, NJModerate · AQI90 61 · ZIP 0701670
    • Warren County, NJModerate · AQI90 61 · ZIP 0782070
    • Hunterdon County, NJModerate · AQI90 61 · ZIP 0783070
    • Mercer County, NJModerate · AQI90 63 · ZIP 0852069
    • Camden County, NJModerate · AQI90 64 · ZIP 0800268
17. 17Maryland16 monitored countiesModerate71

    • Charles County, MDGood · AQI90 49 · ZIP 2060176
    • Calvert County, MDGood · AQI90 48 · ZIP 2061576
    • Carroll County, MDGood · AQI90 50 · ZIP 2104875
    • Dorchester County, MDModerate · AQI90 52 · ZIP 2161374
    • Howard County, MDModerate · AQI90 54 · ZIP 2070173
    • Montgomery County, MDModerate · AQI90 54 · ZIP 2081273
    • Garrett County, MDModerate · AQI90 54 · ZIP 2152073
    • Kent County, MDModerate · AQI90 55 · ZIP 2161073
    • Prince George's County, MDModerate · AQI90 57 · ZIP 2060772
    • Anne Arundel County, MDModerate · AQI90 58 · ZIP 2071171
    • Frederick County, MDModerate · AQI90 58 · ZIP 2170171
    • Washington County, MDModerate · AQI90 58 · ZIP 2171171
    • Harford County, MDModerate · AQI90 61 · ZIP 2100170
    • Cecil County, MDModerate · AQI90 60 · ZIP 2190170
    • Baltimore County, MDModerate · AQI90 65 · ZIP 2101368
    • Baltimore city, MDModerate · AQI90 64 · ZIP 2120168
18. 18North Carolina34 monitored countiesModerate71

    • Martin County, NCGood · AQI90 41 · ZIP 2782580
    • Hyde County, NCGood · AQI90 44 · ZIP 2781078
    • Macon County, NCGood · AQI90 44 · ZIP 2873478
    • Rockingham County, NCGood · AQI90 47 · ZIP 2702577
    • Caswell County, NCGood · AQI90 47 · ZIP 2721277
    • Person County, NCGood · AQI90 47 · ZIP 2734377
    • Lenoir County, NCGood · AQI90 47 · ZIP 2850177
    • Carteret County, NCGood · AQI90 46 · ZIP 2851177
    • Caldwell County, NCGood · AQI90 46 · ZIP 2861177
    • Granville County, NCGood · AQI90 49 · ZIP 2750776
    • Avery County, NCGood · AQI90 49 · ZIP 2861676
    • Alexander County, NCGood · AQI90 49 · ZIP 2863676
    • Lincoln County, NCModerate · AQI90 51 · ZIP 2803375
    • Union County, NCGood · AQI90 50 · ZIP 2807975
    • Graham County, NCModerate · AQI90 51 · ZIP 2870275
    • Haywood County, NCModerate · AQI90 51 · ZIP 2871675
    • Montgomery County, NCModerate · AQI90 53 · ZIP 2720974
    • Edgecombe County, NCModerate · AQI90 53 · ZIP 2780174
    • Pitt County, NCModerate · AQI90 52 · ZIP 2781274
    • Northampton County, NCModerate · AQI90 55 · ZIP 2782073
    • New Hanover County, NCModerate · AQI90 55 · ZIP 2840173
    • Mitchell County, NCModerate · AQI90 54 · ZIP 2870573
    • Swain County, NCModerate · AQI90 54 · ZIP 2871373
    • Rowan County, NCModerate · AQI90 57 · ZIP 2701372
    • Guilford County, NCModerate · AQI90 56 · ZIP 2721472
    • Durham County, NCModerate · AQI90 57 · ZIP 2750372
    • Johnston County, NCModerate · AQI90 56 · ZIP 2750472
    • Cumberland County, NCModerate · AQI90 57 · ZIP 2830172
    • Buncombe County, NCModerate · AQI90 57 · ZIP 2870172
    • Wake County, NCModerate · AQI90 58 · ZIP 2750271
    • Catawba County, NCModerate · AQI90 58 · ZIP 2860171
    • Davidson County, NCModerate · AQI90 61 · ZIP 2710770
    • Forsyth County, NCModerate · AQI90 63 · ZIP 2700969
    • Mecklenburg County, NCModerate · AQI90 63 · ZIP 2803169
19. 19South Carolina13 monitored countiesModerate71

    • Berkeley County, SCGood · AQI90 48 · ZIP 2941076
    • Darlington County, SCModerate · AQI90 51 · ZIP 2906975
    • Aiken County, SCGood · AQI90 50 · ZIP 2910575
    • Anderson County, SCGood · AQI90 50 · ZIP 2962175
    • Horry County, SCModerate · AQI90 55 · ZIP 2951173
    • Chesterfield County, SCModerate · AQI90 58 · ZIP 2910171
    • Florence County, SCModerate · AQI90 58 · ZIP 2911471
    • Charleston County, SCModerate · AQI90 59 · ZIP 2940171
    • York County, SCModerate · AQI90 58 · ZIP 2970471
    • Richland County, SCModerate · AQI90 61 · ZIP 2901670
    • Edgefield County, SCModerate · AQI90 60 · ZIP 2982170
    • Spartanburg County, SCModerate · AQI90 62 · ZIP 2930169
    • Greenville County, SCModerate · AQI90 64 · ZIP 2935668
20. 20Alabama15 monitored countiesModerate71

    • Elmore County, ALGood · AQI90 46 · ZIP 3602077
    • Shelby County, ALGood · AQI90 49 · ZIP 3500776
    • Lawrence County, ALGood · AQI90 48 · ZIP 3561876
    • Clay County, ALModerate · AQI90 55 · ZIP 3508273
    • Sumter County, ALModerate · AQI90 54 · ZIP 3545973
    • Morgan County, ALModerate · AQI90 55 · ZIP 3560173
    • Mobile County, ALModerate · AQI90 55 · ZIP 3650573
    • Baldwin County, ALModerate · AQI90 55 · ZIP 3650773
    • Russell County, ALModerate · AQI90 55 · ZIP 3685173
    • Tuscaloosa County, ALModerate · AQI90 56 · ZIP 3540172
    • Madison County, ALModerate · AQI90 57 · ZIP 3574172
    • DeKalb County, ALModerate · AQI90 56 · ZIP 3596172
    • Montgomery County, ALModerate · AQI90 57 · ZIP 3601372
    • Etowah County, ALModerate · AQI90 60 · ZIP 3590170
    • Jefferson County, ALModerate · AQI90 68 · ZIP 3500566
21. 21Mississippi10 monitored countiesModerate71

    • Yalobusha County, MSGood · AQI90 45 · ZIP 3892278
    • Lee County, MSGood · AQI90 48 · ZIP 3880176
    • Lauderdale County, MSGood · AQI90 48 · ZIP 3930176
    • Bolivar County, MSModerate · AQI90 58 · ZIP 3872571
    • Forrest County, MSModerate · AQI90 59 · ZIP 3940171
    • Hancock County, MSModerate · AQI90 58 · ZIP 3952071
    • Jackson County, MSModerate · AQI90 59 · ZIP 3955371
    • DeSoto County, MSModerate · AQI90 61 · ZIP 3863270
    • Hinds County, MSModerate · AQI90 63 · ZIP 3904169
    • Harrison County, MSModerate · AQI90 62 · ZIP 3950169
22. 22South Dakota10 monitored countiesModerate71

    • Hughes County, SDGood · AQI90 45 · ZIP 5750178
    • Meade County, SDGood · AQI90 46 · ZIP 5770677
    • Clay County, SDModerate · AQI90 53 · ZIP 5701074
    • Jackson County, SDModerate · AQI90 55 · ZIP 5754373
    • Brown County, SDModerate · AQI90 56 · ZIP 5740172
    • Minnehaha County, SDModerate · AQI90 58 · ZIP 5700371
    • Codington County, SDModerate · AQI90 58 · ZIP 5720171
    • Custer County, SDModerate · AQI90 58 · ZIP 5773071
    • Pennington County, SDModerate · AQI90 62 · ZIP 5770169
    • Brookings County, SDModerate · AQI90 66 · ZIP 5700267
23. 23Nebraska11 monitored countiesModerate71

    • Cass County, NEGood · AQI90 36 · ZIP 6801682
    • Thomas County, NEGood · AQI90 43 · ZIP 6914279
    • Scotts Bluff County, NEGood · AQI90 42 · ZIP 6934179
    • Knox County, NEGood · AQI90 48 · ZIP 6871876
    • Washington County, NEModerate · AQI90 53 · ZIP 6800274
    • Lancaster County, NEModerate · AQI90 54 · ZIP 6831773
    • Hall County, NEModerate · AQI90 54 · ZIP 6880173
    • Sarpy County, NEModerate · AQI90 56 · ZIP 6800572
    • Gage County, NEModerate · AQI90 58 · ZIP 6830171
    • Sioux County, NEModerate · AQI90 58 · ZIP 6934671
    • Douglas County, NEModerate · AQI90 62 · ZIP 6800769
24. 24Louisiana22 monitored countiesModerate71

    • Ascension Parish, LAGood · AQI90 47 · ZIP 7034677
    • St. John the Baptist Parish, LAGood · AQI90 48 · ZIP 7004976
    • St. James Parish, LAGood · AQI90 48 · ZIP 7005276
    • Pointe Coupee Parish, LAGood · AQI90 48 · ZIP 7071576
    • St. Martin Parish, LAGood · AQI90 50 · ZIP 7051775
    • Tangipahoa Parish, LAModerate · AQI90 53 · ZIP 7040174
    • Orleans Parish, LAModerate · AQI90 55 · ZIP 7011273
    • Lafourche Parish, LAModerate · AQI90 57 · ZIP 7030172
    • Caddo Parish, LAModerate · AQI90 57 · ZIP 7100472
    • Bossier Parish, LAModerate · AQI90 57 · ZIP 7100672
    • Rapides Parish, LAModerate · AQI90 57 · ZIP 7130172
    • St. Bernard Parish, LAModerate · AQI90 58 · ZIP 7003271
    • Terrebonne Parish, LAModerate · AQI90 58 · ZIP 7034471
    • St. Tammany Parish, LAModerate · AQI90 58 · ZIP 7042071
    • Livingston Parish, LAModerate · AQI90 59 · ZIP 7044971
    • Lafayette Parish, LAModerate · AQI90 59 · ZIP 7050171
    • Ouachita Parish, LAModerate · AQI90 58 · ZIP 7120171
    • Calcasieu Parish, LAModerate · AQI90 61 · ZIP 7060170
    • West Baton Rouge Parish, LAModerate · AQI90 61 · ZIP 7071070
    • Iberville Parish, LAModerate · AQI90 61 · ZIP 7072170
    • Jefferson Parish, LAModerate · AQI90 63 · ZIP 7000169
    • East Baton Rouge Parish, LAModerate · AQI90 63 · ZIP 7071469
25. 25Oregon21 monitored countiesModerate71

    • Columbia County, ORGood · AQI90 45 · ZIP 9701678
    • Clackamas County, ORModerate · AQI90 53 · ZIP 9700474
    • Deschutes County, ORModerate · AQI90 52 · ZIP 9770174
    • Wallowa County, ORModerate · AQI90 53 · ZIP 9782874
    • Wasco County, ORModerate · AQI90 54 · ZIP 9700173
    • Baker County, ORModerate · AQI90 54 · ZIP 9781473
    • Union County, ORModerate · AQI90 54 · ZIP 9782473
    • Washington County, ORModerate · AQI90 57 · ZIP 9700372
    • Multnomah County, ORModerate · AQI90 57 · ZIP 9701972
    • Linn County, ORModerate · AQI90 57 · ZIP 9732172
    • Marion County, ORModerate · AQI90 58 · ZIP 9700271
    • Harney County, ORModerate · AQI90 60 · ZIP 9771070
    • Lake County, ORModerate · AQI90 62 · ZIP 9762069
    • Jefferson County, ORModerate · AQI90 63 · ZIP 9771169
    • Crook County, ORModerate · AQI90 65 · ZIP 9775168
    • Umatilla County, ORModerate · AQI90 64 · ZIP 9780168
    • Josephine County, ORModerate · AQI90 67 · ZIP 9749767
    • Jackson County, ORModerate · AQI90 67 · ZIP 9750167
    • Grant County, ORModerate · AQI90 67 · ZIP 9781767
    • Lane County, ORModerate · AQI90 68 · ZIP 9740166
    • Klamath County, ORModerate · AQI90 69 · ZIP 9760166
26. 26Washington31 monitored countiesModerate71

    • Pacific County, WAGood · AQI90 26 · ZIP 9852787
    • Jefferson County, WAGood · AQI90 36 · ZIP 9832082
    • Skagit County, WAGood · AQI90 40 · ZIP 9822180
    • Grays Harbor County, WAGood · AQI90 41 · ZIP 9852080
    • Kitsap County, WAGood · AQI90 42 · ZIP 9811079
    • Garfield County, WAGood · AQI90 45 · ZIP 9934778
    • Whatcom County, WAGood · AQI90 46 · ZIP 9822077
    • Thurston County, WAGood · AQI90 47 · ZIP 9850177
    • Lewis County, WAGood · AQI90 48 · ZIP 9833676
    • Mason County, WAGood · AQI90 48 · ZIP 9852476
    • Cowlitz County, WAGood · AQI90 49 · ZIP 9858176
    • Adams County, WAGood · AQI90 50 · ZIP 9910575
    • Columbia County, WAGood · AQI90 50 · ZIP 9932875
    • Clallam County, WAModerate · AQI90 53 · ZIP 9830574
    • Klickitat County, WAModerate · AQI90 53 · ZIP 9860274
    • Franklin County, WAModerate · AQI90 52 · ZIP 9930174
    • Whitman County, WAModerate · AQI90 54 · ZIP 9901773
    • Kittitas County, WAModerate · AQI90 57 · ZIP 9806872
    • Clark County, WAModerate · AQI90 56 · ZIP 9860172
    • Benton County, WAModerate · AQI90 57 · ZIP 9894472
    • Walla Walla County, WAModerate · AQI90 56 · ZIP 9932372
    • Pierce County, WAModerate · AQI90 58 · ZIP 9830371
    • Grant County, WAModerate · AQI90 59 · ZIP 9882371
    • King County, WAModerate · AQI90 61 · ZIP 9800170
    • Snohomish County, WAModerate · AQI90 61 · ZIP 9801270
    • Spokane County, WAModerate · AQI90 63 · ZIP 9900169
    • Stevens County, WAModerate · AQI90 63 · ZIP 9901369
    • Okanogan County, WAModerate · AQI90 67 · ZIP 9881267
    • Asotin County, WAModerate · AQI90 67 · ZIP 9940167
    • Chelan County, WAModerate · AQI90 68 · ZIP 9880166
    • Yakima County, WAModerate · AQI90 68 · ZIP 9890166
27. 27Georgia26 monitored countiesModerate70

    • Cobb County, GAGood · AQI90 47 · ZIP 3000877
    • Dawson County, GAGood · AQI90 46 · ZIP 3014877
    • Charlton County, GAGood · AQI90 46 · ZIP 3153777
    • Rockdale County, GAGood · AQI90 48 · ZIP 3001276
    • Pike County, GAModerate · AQI90 51 · ZIP 3020675
    • Murray County, GAGood · AQI90 50 · ZIP 3070575
    • Henry County, GAModerate · AQI90 56 · ZIP 3022872
    • Glynn County, GAModerate · AQI90 57 · ZIP 3152072
    • Douglas County, GAModerate · AQI90 58 · ZIP 3012271
    • Chatham County, GAModerate · AQI90 59 · ZIP 3130271
    • DeKalb County, GAModerate · AQI90 61 · ZIP 3000270
    • Clayton County, GAModerate · AQI90 60 · ZIP 3023670
    • Houston County, GAModerate · AQI90 61 · ZIP 3100570
    • Washington County, GAModerate · AQI90 60 · ZIP 3101870
    • Coffee County, GAModerate · AQI90 61 · ZIP 3151270
    • Floyd County, GAModerate · AQI90 62 · ZIP 3010569
    • Hall County, GAModerate · AQI90 62 · ZIP 3050169
    • Clarke County, GAModerate · AQI90 63 · ZIP 3060169
    • Fulton County, GAModerate · AQI90 64 · ZIP 3000468
    • Walker County, GAModerate · AQI90 64 · ZIP 3070768
    • Lowndes County, GAModerate · AQI90 65 · ZIP 3160168
    • Dougherty County, GAModerate · AQI90 64 · ZIP 3170168
    • Muscogee County, GAModerate · AQI90 65 · ZIP 3182068
    • Gwinnett County, GAModerate · AQI90 66 · ZIP 3001767
    • Bibb County, GAModerate · AQI90 68 · ZIP 3105266
    • Richmond County, GAModerate · AQI90 70 · ZIP 3080565
28. 28Tennessee23 monitored countiesModerate70

    • Claiborne County, TNGood · AQI90 45 · ZIP 3771578
    • DeKalb County, TNGood · AQI90 46 · ZIP 3701277
    • Sevier County, TNGood · AQI90 47 · ZIP 3773877
    • Wilson County, TNGood · AQI90 48 · ZIP 3701676
    • Anderson County, TNGood · AQI90 48 · ZIP 3770576
    • Williamson County, TNModerate · AQI90 51 · ZIP 3701475
    • Jefferson County, TNGood · AQI90 50 · ZIP 3772575
    • Putnam County, TNModerate · AQI90 51 · ZIP 3850175
    • Maury County, TNModerate · AQI90 53 · ZIP 3717474
    • Loudon County, TNModerate · AQI90 53 · ZIP 3774274
    • Roane County, TNModerate · AQI90 52 · ZIP 3774874
    • Lawrence County, TNModerate · AQI90 53 · ZIP 3845674
    • Montgomery County, TNModerate · AQI90 54 · ZIP 3704073
    • Sullivan County, TNModerate · AQI90 55 · ZIP 3761773
    • Dyer County, TNModerate · AQI90 55 · ZIP 3800773
    • McMinn County, TNModerate · AQI90 56 · ZIP 3730372
    • Blount County, TNModerate · AQI90 57 · ZIP 3770172
    • Madison County, TNModerate · AQI90 56 · ZIP 3830172
    • Hamilton County, TNModerate · AQI90 61 · ZIP 3730270
    • Knox County, TNModerate · AQI90 60 · ZIP 3772170
    • Sumner County, TNModerate · AQI90 62 · ZIP 3702269
    • Davidson County, TNModerate · AQI90 64 · ZIP 3701368
    • Shelby County, TNModerate · AQI90 67 · ZIP 3800267
29. 29Kentucky25 monitored countiesModerate70

    • Greenup County, KYGood · AQI90 46 · ZIP 4112177
    • Morgan County, KYGood · AQI90 47 · ZIP 4133277
    • Simpson County, KYGood · AQI90 49 · ZIP 4213476
    • Edmonson County, KYGood · AQI90 49 · ZIP 4216076
    • Oldham County, KYModerate · AQI90 51 · ZIP 4001075
    • Washington County, KYGood · AQI90 50 · ZIP 4004075
    • Carter County, KYModerate · AQI90 51 · ZIP 4113275
    • Livingston County, KYModerate · AQI90 51 · ZIP 4202875
    • Perry County, KYModerate · AQI90 52 · ZIP 4098174
    • Pike County, KYModerate · AQI90 52 · ZIP 4150174
    • Bullitt County, KYModerate · AQI90 54 · ZIP 4004773
    • Boone County, KYModerate · AQI90 54 · ZIP 4100573
    • Boyd County, KYModerate · AQI90 54 · ZIP 4110173
    • Warren County, KYModerate · AQI90 54 · ZIP 4210173
    • Pulaski County, KYModerate · AQI90 54 · ZIP 4250173
    • Jessamine County, KYModerate · AQI90 57 · ZIP 4033972
    • Fayette County, KYModerate · AQI90 57 · ZIP 4050272
    • Campbell County, KYModerate · AQI90 57 · ZIP 4100172
    • Christian County, KYModerate · AQI90 57 · ZIP 4221572
    • Hardin County, KYModerate · AQI90 58 · ZIP 4012171
    • Bell County, KYModerate · AQI90 59 · ZIP 4081371
    • McCracken County, KYModerate · AQI90 58 · ZIP 4200171
    • Hancock County, KYModerate · AQI90 58 · ZIP 4234871
    • Daviess County, KYModerate · AQI90 61 · ZIP 4230170
    • Jefferson County, KYModerate · AQI90 67 · ZIP 4002367
30. 30Kansas12 monitored countiesModerate70

    • Douglas County, KSGood · AQI90 49 · ZIP 6600676
    • Leavenworth County, KSGood · AQI90 48 · ZIP 6600776
    • Sherman County, KSGood · AQI90 49 · ZIP 6773376
    • Ford County, KSModerate · AQI90 51 · ZIP 6780175
    • Chase County, KSModerate · AQI90 54 · ZIP 6684373
    • Johnson County, KSModerate · AQI90 60 · ZIP 6601870
    • Shawnee County, KSModerate · AQI90 61 · ZIP 6640270
    • Sumner County, KSModerate · AQI90 61 · ZIP 6700470
    • Trego County, KSModerate · AQI90 61 · ZIP 6763170
    • Neosho County, KSModerate · AQI90 62 · ZIP 6672069
    • Sedgwick County, KSModerate · AQI90 63 · ZIP 6700169
    • Wyandotte County, KSModerate · AQI90 66 · ZIP 6610167
31. 31New York27 monitored countiesModerate69

    • Saratoga County, NYGood · AQI90 44 · ZIP 1201978
    • Hamilton County, NYGood · AQI90 44 · ZIP 1203278
    • Oswego County, NYGood · AQI90 44 · ZIP 1302878
    • Wayne County, NYGood · AQI90 45 · ZIP 1314378
    • Putnam County, NYGood · AQI90 46 · ZIP 1050977
    • Dutchess County, NYGood · AQI90 46 · ZIP 1250177
    • Tompkins County, NYGood · AQI90 47 · ZIP 1305377
    • Jefferson County, NYGood · AQI90 47 · ZIP 1360177
    • Niagara County, NYGood · AQI90 48 · ZIP 1400876
    • Orange County, NYModerate · AQI90 53 · ZIP 1091074
    • Chautauqua County, NYModerate · AQI90 52 · ZIP 1404874
    • Oneida County, NYModerate · AQI90 54 · ZIP 1304273
    • Westchester County, NYModerate · AQI90 56 · ZIP 1050172
    • Rockland County, NYModerate · AQI90 56 · ZIP 1090172
    • Onondaga County, NYModerate · AQI90 57 · ZIP 1302072
    • Steuben County, NYModerate · AQI90 57 · ZIP 1452972
    • Nassau County, NYModerate · AQI90 58 · ZIP 1100171
    • Richmond County, NYModerate · AQI90 61 · ZIP 1030170
    • Essex County, NYModerate · AQI90 61 · ZIP 1285170
    • Monroe County, NYModerate · AQI90 61 · ZIP 1442070
    • Kings County, NYModerate · AQI90 63 · ZIP 1120169
    • Suffolk County, NYModerate · AQI90 64 · ZIP 0639068
    • Queens County, NYModerate · AQI90 64 · ZIP 1100468
    • Albany County, NYModerate · AQI90 64 · ZIP 1200768
    • Bronx County, NYModerate · AQI90 67 · ZIP 1045167
    • Erie County, NYModerate · AQI90 67 · ZIP 1400167
    • New York County, NYModerate · AQI90 69 · ZIP 1000166
32. 32Missouri21 monitored countiesModerate69

    • Stoddard County, MOGood · AQI90 40 · ZIP 6373080
    • Monroe County, MOGood · AQI90 47 · ZIP 6344377
    • Boone County, MOGood · AQI90 49 · ZIP 6501076
    • Callaway County, MOModerate · AQI90 51 · ZIP 6338875
    • Ste. Genevieve County, MOGood · AQI90 50 · ZIP 6362775
    • Taney County, MOModerate · AQI90 52 · ZIP 6561474
    • Perry County, MOModerate · AQI90 54 · ZIP 6373273
    • Cass County, MOModerate · AQI90 55 · ZIP 6401273
    • Cedar County, MOModerate · AQI90 55 · ZIP 6474473
    • Lincoln County, MOModerate · AQI90 58 · ZIP 6334371
    • Andrew County, MOModerate · AQI90 58 · ZIP 6442171
    • Jasper County, MOModerate · AQI90 58 · ZIP 6475571
    • St. Louis County, MOModerate · AQI90 61 · ZIP 6300570
    • Jefferson County, MOModerate · AQI90 60 · ZIP 6301070
    • Jackson County, MOModerate · AQI90 63 · ZIP 6401469
    • Buchanan County, MOModerate · AQI90 62 · ZIP 6440169
    • Greene County, MOModerate · AQI90 62 · ZIP 6560469
    • Clay County, MOModerate · AQI90 64 · ZIP 6402468
    • Clinton County, MOModerate · AQI90 67 · ZIP 6445467
    • St. Charles County, MOModerate · AQI90 71 · ZIP 6330165
    • St. Louis city, MOModerate · AQI90 77 · ZIP 6310162
33. 33Arkansas11 monitored countiesModerate69

    • Clark County, ARGood · AQI90 46 · ZIP 7172177
    • Newton County, ARGood · AQI90 50 · ZIP 7262475
    • Washington County, ARModerate · AQI90 54 · ZIP 7270173
    • Crittenden County, ARModerate · AQI90 57 · ZIP 7230172
    • Ashley County, ARModerate · AQI90 58 · ZIP 7163571
    • Polk County, ARModerate · AQI90 59 · ZIP 7193771
    • Arkansas County, ARModerate · AQI90 59 · ZIP 7200371
    • Jackson County, ARModerate · AQI90 61 · ZIP 7200570
    • Union County, ARModerate · AQI90 62 · ZIP 7172469
    • Garland County, ARModerate · AQI90 62 · ZIP 7190169
    • Pulaski County, ARModerate · AQI90 69 · ZIP 7205366
34. 34Connecticut8 monitored countiesModerate68

    • Windham County, CTGood · AQI90 47 · ZIP 0622677
    • Tolland County, CTModerate · AQI90 61 · ZIP 0602970
    • New London County, CTModerate · AQI90 60 · ZIP 0624970
    • Litchfield County, CTModerate · AQI90 64 · ZIP 0601868
    • Hartford County, CTModerate · AQI90 68 · ZIP 0600166
    • New Haven County, CTModerate · AQI90 68 · ZIP 0640166
    • Fairfield County, CTModerate · AQI90 74 · ZIP 0646863
    • Middlesex County, CTModerate · AQI90 77 · ZIP 0640962
35. 35Delaware3 monitored countiesModerate68

    • Sussex County, DEModerate · AQI90 57 · ZIP 1993072
    • Kent County, DEModerate · AQI90 62 · ZIP 1990169
    • New Castle County, DEModerate · AQI90 67 · ZIP 1970167
36. 36District of Columbia1 monitored countyModerate68

    • District of Columbia, DCModerate · AQI90 64 · ZIP 2000168
37. 37Iowa15 monitored countiesModerate68

    • Bremer County, IAModerate · AQI90 54 · ZIP 5062273
    • Pottawattamie County, IAModerate · AQI90 57 · ZIP 5150172
    • Muscatine County, IAModerate · AQI90 59 · ZIP 5272071
    • Montgomery County, IAModerate · AQI90 61 · ZIP 5084770
    • Woodbury County, IAModerate · AQI90 61 · ZIP 5100470
    • Johnson County, IAModerate · AQI90 61 · ZIP 5223570
    • Van Buren County, IAModerate · AQI90 61 · ZIP 5253570
    • Black Hawk County, IAModerate · AQI90 63 · ZIP 5061369
    • Polk County, IAModerate · AQI90 64 · ZIP 5000768
    • Webster County, IAModerate · AQI90 65 · ZIP 5050168
    • Harrison County, IAModerate · AQI90 64 · ZIP 5152968
    • Linn County, IAModerate · AQI90 68 · ZIP 5220266
    • Palo Alto County, IAModerate · AQI90 71 · ZIP 5051565
    • Clinton County, IAModerate · AQI90 71 · ZIP 5203765
    • Scott County, IAModerate · AQI90 71 · ZIP 5272265
38. 38Minnesota23 monitored countiesModerate68

    • Pine County, MNGood · AQI90 45 · ZIP 5503078
    • Washington County, MNGood · AQI90 46 · ZIP 5500177
    • Mille Lacs County, MNGood · AQI90 46 · ZIP 5537177
    • Goodhue County, MNModerate · AQI90 51 · ZIP 5500975
    • Cook County, MNModerate · AQI90 54 · ZIP 5560473
    • Winona County, MNModerate · AQI90 55 · ZIP 5591073
    • Cass County, MNModerate · AQI90 59 · ZIP 5643571
    • Ramsey County, MNModerate · AQI90 61 · ZIP 5510170
    • Lake County, MNModerate · AQI90 60 · ZIP 5560170
    • Dakota County, MNModerate · AQI90 62 · ZIP 5502469
    • Stearns County, MNModerate · AQI90 62 · ZIP 5532069
    • Carlton County, MNModerate · AQI90 62 · ZIP 5570769
    • Crow Wing County, MNModerate · AQI90 63 · ZIP 5640169
    • Anoka County, MNModerate · AQI90 64 · ZIP 5500568
    • Scott County, MNModerate · AQI90 64 · ZIP 5502068
    • Olmsted County, MNModerate · AQI90 65 · ZIP 5590168
    • Lyon County, MNModerate · AQI90 65 · ZIP 5611568
    • Wright County, MNModerate · AQI90 67 · ZIP 5530167
    • Beltrami County, MNModerate · AQI90 69 · ZIP 5660166
    • Hennepin County, MNModerate · AQI90 71 · ZIP 5511165
    • Blue Earth County, MNModerate · AQI90 70 · ZIP 5600165
    • Becker County, MNModerate · AQI90 73 · ZIP 5650164
    • St. Louis County, MNModerate · AQI90 79 · ZIP 5560261
39. 39Pennsylvania38 monitored countiesModerate67

    • Somerset County, PAGood · AQI90 46 · ZIP 1541177
    • Elk County, PAGood · AQI90 47 · ZIP 1582177
    • Franklin County, PAGood · AQI90 49 · ZIP 1720176
    • Susquehanna County, PAModerate · AQI90 51 · ZIP 1841375
    • Monroe County, PAModerate · AQI90 52 · ZIP 1805874
    • Wyoming County, PAModerate · AQI90 53 · ZIP 1841974
    • Bradford County, PAModerate · AQI90 54 · ZIP 1691073
    • Tioga County, PAModerate · AQI90 56 · ZIP 1690172
    • Westmoreland County, PAModerate · AQI90 58 · ZIP 1501271
    • Fayette County, PAModerate · AQI90 59 · ZIP 1540171
    • Indiana County, PAModerate · AQI90 59 · ZIP 1568171
    • Cambria County, PAModerate · AQI90 58 · ZIP 1571471
    • Warren County, PAModerate · AQI90 58 · ZIP 1631271
    • Erie County, PAModerate · AQI90 59 · ZIP 1640171
    • Centre County, PAModerate · AQI90 58 · ZIP 1667771
    • Greene County, PAModerate · AQI90 61 · ZIP 1531070
    • Armstrong County, PAModerate · AQI90 61 · ZIP 1561870
    • Blair County, PAModerate · AQI90 60 · ZIP 1660170
    • Adams County, PAModerate · AQI90 61 · ZIP 1730170
    • Lycoming County, PAModerate · AQI90 61 · ZIP 1770170
    • Montgomery County, PAModerate · AQI90 61 · ZIP 1804170
    • Bucks County, PAModerate · AQI90 61 · ZIP 1807770
    • Lackawanna County, PAModerate · AQI90 60 · ZIP 1840370
    • Washington County, PAModerate · AQI90 62 · ZIP 1500469
    • Cumberland County, PAModerate · AQI90 62 · ZIP 1700769
    • Lehigh County, PAModerate · AQI90 63 · ZIP 1801869
    • Mercer County, PAModerate · AQI90 64 · ZIP 1611368
    • Lebanon County, PAModerate · AQI90 65 · ZIP 1700368
    • Dauphin County, PAModerate · AQI90 65 · ZIP 1700568
    • Berks County, PAModerate · AQI90 65 · ZIP 1708768
    • Northampton County, PAModerate · AQI90 64 · ZIP 1801368
    • Delaware County, PAModerate · AQI90 65 · ZIP 1900368
    • Chester County, PAModerate · AQI90 64 · ZIP 1908768
    • York County, PAModerate · AQI90 67 · ZIP 1701967
    • Beaver County, PAModerate · AQI90 71 · ZIP 1500165
    • Lancaster County, PAModerate · AQI90 71 · ZIP 1702265
    • Philadelphia County, PAModerate · AQI90 73 · ZIP 1910264
    • Allegheny County, PAModerate · AQI90 78 · ZIP 1500661
40. 40Indiana33 monitored countiesModerate67

    • Brown County, INGood · AQI90 46 · ZIP 4616077
    • Hendricks County, INGood · AQI90 49 · ZIP 4610376
    • Shelby County, INGood · AQI90 49 · ZIP 4611076
    • Carroll County, INGood · AQI90 49 · ZIP 4691376
    • Wabash County, INGood · AQI90 49 · ZIP 4694076
    • Knox County, INGood · AQI90 49 · ZIP 4751276
    • Perry County, INGood · AQI90 49 · ZIP 4751476
    • Boone County, INModerate · AQI90 51 · ZIP 4605275
    • Posey County, INGood · AQI90 50 · ZIP 4762075
    • Warrick County, INModerate · AQI90 54 · ZIP 4752373
    • Henry County, INModerate · AQI90 59 · ZIP 4614871
    • Bartholomew County, INModerate · AQI90 59 · ZIP 4720171
    • Monroe County, INModerate · AQI90 58 · ZIP 4740171
    • Greene County, INModerate · AQI90 59 · ZIP 4742471
    • Dubois County, INModerate · AQI90 58 · ZIP 4751371
    • Spencer County, INModerate · AQI90 59 · ZIP 4753171
    • Tippecanoe County, INModerate · AQI90 58 · ZIP 4790171
    • Madison County, INModerate · AQI90 61 · ZIP 4600170
    • Whitley County, INModerate · AQI90 61 · ZIP 4672370
    • Howard County, INModerate · AQI90 61 · ZIP 4690170
    • Clark County, INModerate · AQI90 61 · ZIP 4710470
    • Floyd County, INModerate · AQI90 61 · ZIP 4711970
    • Hamilton County, INModerate · AQI90 62 · ZIP 4603069
    • Delaware County, INModerate · AQI90 63 · ZIP 4730269
    • Vanderburgh County, INModerate · AQI90 63 · ZIP 4770869
    • Vigo County, INModerate · AQI90 65 · ZIP 4780268
    • Elkhart County, INModerate · AQI90 66 · ZIP 4650767
    • Allen County, INModerate · AQI90 69 · ZIP 4670466
    • Marion County, INModerate · AQI90 71 · ZIP 4610765
    • Porter County, INModerate · AQI90 71 · ZIP 4630165
    • St. Joseph County, INModerate · AQI90 71 · ZIP 4653065
    • LaPorte County, INModerate · AQI90 72 · ZIP 4634064
    • Lake County, INModerate · AQI90 75 · ZIP 4630363
41. 41Wisconsin29 monitored countiesModerate67

    • Taylor County, WIGood · AQI90 46 · ZIP 5443377
    • Vilas County, WIGood · AQI90 49 · ZIP 5451276
    • La Crosse County, WIGood · AQI90 49 · ZIP 5460176
    • Fond du Lac County, WIGood · AQI90 50 · ZIP 5301075
    • Jefferson County, WIModerate · AQI90 54 · ZIP 5303673
    • Manitowoc County, WIModerate · AQI90 58 · ZIP 5301571
    • Columbia County, WIModerate · AQI90 58 · ZIP 5355571
    • Sauk County, WIModerate · AQI90 58 · ZIP 5356171
    • Rock County, WIModerate · AQI90 61 · ZIP 5350170
    • Marathon County, WIModerate · AQI90 61 · ZIP 5440170
    • Dodge County, WIModerate · AQI90 63 · ZIP 5300369
    • Grant County, WIModerate · AQI90 63 · ZIP 5355469
    • Ashland County, WIModerate · AQI90 62 · ZIP 5451469
    • Jackson County, WIModerate · AQI90 63 · ZIP 5461169
    • Monroe County, WIModerate · AQI90 62 · ZIP 5461969
    • Eau Claire County, WIModerate · AQI90 62 · ZIP 5470169
    • Dane County, WIModerate · AQI90 64 · ZIP 5350868
    • Forest County, WIModerate · AQI90 64 · ZIP 5410368
    • Outagamie County, WIModerate · AQI90 64 · ZIP 5410668
    • Door County, WIModerate · AQI90 64 · ZIP 5420268
    • Ozaukee County, WIModerate · AQI90 67 · ZIP 5300467
    • Walworth County, WIModerate · AQI90 67 · ZIP 5311467
    • Brown County, WIModerate · AQI90 66 · ZIP 5411567
    • Kewaunee County, WIModerate · AQI90 67 · ZIP 5420167
    • Waukesha County, WIModerate · AQI90 69 · ZIP 5300566
    • Milwaukee County, WIModerate · AQI90 74 · ZIP 5311063
    • Sheboygan County, WIModerate · AQI90 77 · ZIP 5300162
    • Kenosha County, WIModerate · AQI90 77 · ZIP 5310462
    • Racine County, WIModerate · AQI90 77 · ZIP 5310562
42. 42North Dakota9 monitored countiesModerate67

    • Mercer County, NDModerate · AQI90 59 · ZIP 5852371
    • Oliver County, NDModerate · AQI90 58 · ZIP 5853071
    • Burleigh County, NDModerate · AQI90 60 · ZIP 5847770
    • Billings County, NDModerate · AQI90 60 · ZIP 5862270
    • Dunn County, NDModerate · AQI90 61 · ZIP 5862570
    • McKenzie County, NDModerate · AQI90 61 · ZIP 5863470
    • Ward County, NDModerate · AQI90 60 · ZIP 5870170
    • Burke County, NDModerate · AQI90 67 · ZIP 5872167
    • Cass County, NDModerate · AQI90 71 · ZIP 5800265
43. 43Ohio37 monitored countiesModerate66

    • Columbiana County, OHGood · AQI90 22 · ZIP 4392089
    • Knox County, OHModerate · AQI90 54 · ZIP 4300573
    • Noble County, OHModerate · AQI90 54 · ZIP 4371173
    • Lorain County, OHModerate · AQI90 54 · ZIP 4400173
    • Athens County, OHModerate · AQI90 54 · ZIP 4570173
    • Washington County, OHModerate · AQI90 54 · ZIP 4571473
    • Wood County, OHModerate · AQI90 58 · ZIP 4340271
    • Clermont County, OHModerate · AQI90 58 · ZIP 4510271
    • Greene County, OHModerate · AQI90 58 · ZIP 4530171
    • Lawrence County, OHModerate · AQI90 59 · ZIP 4561971
    • Licking County, OHModerate · AQI90 61 · ZIP 4300170
    • Delaware County, OHModerate · AQI90 61 · ZIP 4301570
    • Ashtabula County, OHModerate · AQI90 61 · ZIP 4400370
    • Geauga County, OHModerate · AQI90 61 · ZIP 4402170
    • Clinton County, OHModerate · AQI90 61 · ZIP 4510770
    • Miami County, OHModerate · AQI90 61 · ZIP 4531270
    • Allen County, OHModerate · AQI90 61 · ZIP 4580170
    • Clark County, OHModerate · AQI90 65 · ZIP 4301068
    • Belmont County, OHModerate · AQI90 65 · ZIP 4371368
    • Mahoning County, OHModerate · AQI90 65 · ZIP 4440168
    • Preble County, OHModerate · AQI90 64 · ZIP 4500368
    • Scioto County, OHModerate · AQI90 64 · ZIP 4562968
    • Summit County, OHModerate · AQI90 67 · ZIP 4405667
    • Medina County, OHModerate · AQI90 67 · ZIP 4421267
    • Warren County, OHModerate · AQI90 67 · ZIP 4500567
    • Montgomery County, OHModerate · AQI90 67 · ZIP 4530967
    • Jefferson County, OHModerate · AQI90 68 · ZIP 4390166
    • Madison County, OHModerate · AQI90 71 · ZIP 4302965
    • Lake County, OHModerate · AQI90 71 · ZIP 4404565
    • Portage County, OHModerate · AQI90 71 · ZIP 4420165
    • Stark County, OHModerate · AQI90 70 · ZIP 4460165
    • Hamilton County, OHModerate · AQI90 71 · ZIP 4500165
    • Lucas County, OHModerate · AQI90 72 · ZIP 4341264
    • Franklin County, OHModerate · AQI90 74 · ZIP 4300263
    • Trumbull County, OHModerate · AQI90 74 · ZIP 4440263
    • Butler County, OHModerate · AQI90 77 · ZIP 4501162
    • Cuyahoga County, OHModerate · AQI90 78 · ZIP 4401761
44. 44Michigan27 monitored countiesModerate66

    • Keweenaw County, MIGood · AQI90 16 · ZIP 4980592
    • Tuscola County, MIGood · AQI90 49 · ZIP 4843576
    • Wexford County, MIGood · AQI90 48 · ZIP 4960176
    • Huron County, MIModerate · AQI90 51 · ZIP 4841375
    • Clinton County, MIGood · AQI90 50 · ZIP 4880875
    • Mason County, MIModerate · AQI90 51 · ZIP 4940575
    • Benzie County, MIGood · AQI90 50 · ZIP 4961675
    • Genesee County, MIModerate · AQI90 57 · ZIP 4841172
    • Missaukee County, MIModerate · AQI90 58 · ZIP 4963271
    • Bay County, MIModerate · AQI90 60 · ZIP 4861170
    • Cass County, MIModerate · AQI90 61 · ZIP 4903170
    • Muskegon County, MIModerate · AQI90 61 · ZIP 4930370
    • Ingham County, MIModerate · AQI90 62 · ZIP 4881969
    • Marquette County, MIModerate · AQI90 62 · ZIP 4980869
    • Manistee County, MIModerate · AQI90 65 · ZIP 4961368
    • Schoolcraft County, MIModerate · AQI90 64 · ZIP 4983668
    • St. Clair County, MIModerate · AQI90 67 · ZIP 4800167
    • Oakland County, MIModerate · AQI90 67 · ZIP 4800967
    • Berrien County, MIModerate · AQI90 67 · ZIP 4902267
    • Lenawee County, MIModerate · AQI90 66 · ZIP 4922067
    • Macomb County, MIModerate · AQI90 68 · ZIP 4800566
    • Washtenaw County, MIModerate · AQI90 68 · ZIP 4810366
    • Ottawa County, MIModerate · AQI90 68 · ZIP 4940166
    • Kalamazoo County, MIModerate · AQI90 71 · ZIP 4900165
    • Kent County, MIModerate · AQI90 72 · ZIP 4930164
    • Wayne County, MIModerate · AQI90 75 · ZIP 4810163
    • Allegan County, MIModerate · AQI90 75 · ZIP 4901063
45. 45Oklahoma20 monitored countiesModerate66

    • Mayes County, OKGood · AQI90 49 · ZIP 7433076
    • Grant County, OKModerate · AQI90 53 · ZIP 7375874
    • Carter County, OKModerate · AQI90 55 · ZIP 7340173
    • Sequoyah County, OKModerate · AQI90 57 · ZIP 7443572
    • Kay County, OKModerate · AQI90 57 · ZIP 7460172
    • Canadian County, OKModerate · AQI90 61 · ZIP 7301470
    • Kiowa County, OKModerate · AQI90 61 · ZIP 7304170
    • Osage County, OKModerate · AQI90 61 · ZIP 7400170
    • Washington County, OKModerate · AQI90 61 · ZIP 7400670
    • Creek County, OKModerate · AQI90 61 · ZIP 7401070
    • Cleveland County, OKModerate · AQI90 65 · ZIP 7301968
    • Pittsburg County, OKModerate · AQI90 64 · ZIP 7442568
    • Adair County, OKModerate · AQI90 65 · ZIP 7493168
    • McClain County, OKModerate · AQI90 67 · ZIP 7303167
    • Comanche County, OKModerate · AQI90 67 · ZIP 7350167
    • Ottawa County, OKModerate · AQI90 66 · ZIP 7433967
    • Oklahoma County, OKModerate · AQI90 71 · ZIP 7300365
    • Dewey County, OKModerate · AQI90 71 · ZIP 7365865
    • Tulsa County, OKModerate · AQI90 74 · ZIP 7400863
    • Love County, OKModerate · AQI90 80 · ZIP 7343060
46. 46Colorado30 monitored countiesModerate64

    • Jackson County, COGood · AQI90 26 · ZIP 8043087
    • San Juan County, COGood · AQI90 29 · ZIP 8143386
    • Routt County, COGood · AQI90 42 · ZIP 8042879
    • Pitkin County, COGood · AQI90 43 · ZIP 8161179
    • Prowers County, COGood · AQI90 45 · ZIP 8104178
    • Fremont County, COGood · AQI90 45 · ZIP 8121278
    • Alamosa County, COGood · AQI90 49 · ZIP 8110176
    • Delta County, COModerate · AQI90 53 · ZIP 8141074
    • Grand County, COModerate · AQI90 61 · ZIP 8044270
    • Archuleta County, COModerate · AQI90 61 · ZIP 8112170
    • San Miguel County, COModerate · AQI90 60 · ZIP 8142370
    • Gilpin County, COModerate · AQI90 64 · ZIP 8042268
    • Pueblo County, COModerate · AQI90 64 · ZIP 8100168
    • Montezuma County, COModerate · AQI90 64 · ZIP 8132168
    • Mesa County, COModerate · AQI90 64 · ZIP 8150168
    • El Paso County, COModerate · AQI90 67 · ZIP 8013267
    • Clear Creek County, COModerate · AQI90 67 · ZIP 8043667
    • Gunnison County, COModerate · AQI90 67 · ZIP 8121067
    • Garfield County, COModerate · AQI90 67 · ZIP 8160167
    • Arapahoe County, COModerate · AQI90 71 · ZIP 8001065
    • Adams County, COModerate · AQI90 71 · ZIP 8001165
    • Boulder County, COModerate · AQI90 71 · ZIP 8002565
    • Douglas County, COModerate · AQI90 71 · ZIP 8010465
    • Denver County, COModerate · AQI90 74 · ZIP 8020263
    • La Plata County, COModerate · AQI90 74 · ZIP 8112263
    • Park County, COModerate · AQI90 77 · ZIP 8042062
    • Weld County, COModerate · AQI90 80 · ZIP 8050460
    • Jefferson County, COModerate · AQI90 84 · ZIP 8000258
    • Larimer County, COModerate · AQI90 84 · ZIP 8051258
    • Chaffee County, COModerate · AQI90 84 · ZIP 8120158
47. 47Illinois23 monitored countiesModerate62

    • Jo Daviess County, ILGood · AQI90 46 · ZIP 6100177
    • Effingham County, ILGood · AQI90 46 · ZIP 6240177
    • Macoupin County, ILGood · AQI90 49 · ZIP 6200976
    • Adams County, ILGood · AQI90 49 · ZIP 6230176
    • Clark County, ILGood · AQI90 48 · ZIP 6242076
    • Lake County, ILModerate · AQI90 61 · ZIP 6000270
    • Rock Island County, ILModerate · AQI90 61 · ZIP 6120170
    • Randolph County, ILModerate · AQI90 61 · ZIP 6221770
    • Sangamon County, ILModerate · AQI90 61 · ZIP 6251570
    • Hamilton County, ILModerate · AQI90 61 · ZIP 6281770
    • St. Clair County, ILModerate · AQI90 63 · ZIP 6205969
    • Macon County, ILModerate · AQI90 64 · ZIP 6175668
    • DuPage County, ILModerate · AQI90 67 · ZIP 6010167
    • Champaign County, ILModerate · AQI90 66 · ZIP 6094967
    • Winnebago County, ILModerate · AQI90 67 · ZIP 6101667
    • Peoria County, ILModerate · AQI90 66 · ZIP 6145167
    • McLean County, ILModerate · AQI90 67 · ZIP 6170167
    • Jersey County, ILModerate · AQI90 67 · ZIP 6201267
    • McHenry County, ILModerate · AQI90 71 · ZIP 6001265
    • Will County, ILModerate · AQI90 71 · ZIP 6040165
    • Madison County, ILModerate · AQI90 70 · ZIP 6200165
    • Kane County, ILModerate · AQI90 73 · ZIP 6010964
    • Cook County, ILModerate · AQI90 84 · ZIP 6000458
48. 48Utah17 monitored countiesModerate61

    • Garfield County, UTGood · AQI90 22 · ZIP 8471689
    • Wayne County, UTGood · AQI90 27 · ZIP 8471587
    • San Juan County, UTModerate · AQI90 61 · ZIP 8451170
    • Tooele County, UTModerate · AQI90 64 · ZIP 8402268
    • Cache County, UTModerate · AQI90 64 · ZIP 8430468
    • Grand County, UTModerate · AQI90 64 · ZIP 8451568
    • Iron County, UTModerate · AQI90 64 · ZIP 8471468
    • Washington County, UTModerate · AQI90 64 · ZIP 8472268
    • Box Elder County, UTModerate · AQI90 67 · ZIP 8430167
    • Carbon County, UTModerate · AQI90 67 · ZIP 8450167
    • Utah County, UTModerate · AQI90 73 · ZIP 8400364
    • Duchesne County, UTModerate · AQI90 74 · ZIP 8400163
    • Wasatch County, UTModerate · AQI90 74 · ZIP 8403263
    • Weber County, UTModerate · AQI90 74 · ZIP 8406763
    • Uintah County, UTModerate · AQI90 77 · ZIP 8400862
    • Davis County, UTModerate · AQI90 78 · ZIP 8401061
    • Salt Lake County, UTModerate · AQI90 90 · ZIP 8400655
49. 49New Mexico16 monitored countiesModerate61

    • Los Alamos County, NMGood · AQI90 27 · ZIP 8754787
    • Taos County, NMGood · AQI90 32 · ZIP 8751284
    • Socorro County, NMGood · AQI90 36 · ZIP 8700682
    • Chaves County, NMGood · AQI90 47 · ZIP 8820177
    • Rio Arriba County, NMModerate · AQI90 54 · ZIP 8701273
    • Santa Fe County, NMModerate · AQI90 58 · ZIP 8701071
    • Sandoval County, NMModerate · AQI90 64 · ZIP 8700168
    • Valencia County, NMModerate · AQI90 64 · ZIP 8700268
    • Lea County, NMModerate · AQI90 64 · ZIP 8811468
    • Luna County, NMModerate · AQI90 68 · ZIP 8802966
    • San Juan County, NMModerate · AQI90 74 · ZIP 8703763
    • Catron County, NMModerate · AQI90 74 · ZIP 8782063
    • Lincoln County, NMModerate · AQI90 75 · ZIP 8830163
    • Bernalillo County, NMModerate · AQI90 88 · ZIP 8700856
    • Eddy County, NMModerate · AQI90 90 · ZIP 8821055
    • Doña Ana County, NMUnhealthy for sensitive groups · AQI90 115 · ZIP 8793643
50. 50Texas45 monitored countiesModerate59

    • Karnes County, TXGood · AQI90 16 · ZIP 7811192
    • Wilson County, TXGood · AQI90 19 · ZIP 7811391
    • Potter County, TXGood · AQI90 41 · ZIP 7901080
    • Rockwall County, TXGood · AQI90 45 · ZIP 7503278
    • Lubbock County, TXGood · AQI90 46 · ZIP 7932977
    • Polk County, TXGood · AQI90 48 · ZIP 7593476
    • Ellis County, TXModerate · AQI90 51 · ZIP 7510175
    • Hunt County, TXGood · AQI90 50 · ZIP 7513575
    • Smith County, TXGood · AQI90 50 · ZIP 7570175
    • Gregg County, TXModerate · AQI90 54 · ZIP 7560173
    • Brazos County, TXModerate · AQI90 57 · ZIP 7780172
    • Bowie County, TXModerate · AQI90 59 · ZIP 7550171
    • Harrison County, TXModerate · AQI90 59 · ZIP 7560271
    • Johnson County, TXModerate · AQI90 58 · ZIP 7600971
    • Orange County, TXModerate · AQI90 59 · ZIP 7761171
    • Victoria County, TXModerate · AQI90 58 · ZIP 7790171
    • Ector County, TXModerate · AQI90 58 · ZIP 7974171
    • Kaufman County, TXModerate · AQI90 60 · ZIP 7511470
    • Parker County, TXModerate · AQI90 61 · ZIP 7600870
    • Hood County, TXModerate · AQI90 61 · ZIP 7604870
    • Atascosa County, TXModerate · AQI90 61 · ZIP 7800870
    • Randall County, TXModerate · AQI90 61 · ZIP 7901270
    • Maverick County, TXModerate · AQI90 62 · ZIP 7885269
    • Navarro County, TXModerate · AQI90 65 · ZIP 7510268
    • Bell County, TXModerate · AQI90 65 · ZIP 7650168
    • McLennan County, TXModerate · AQI90 65 · ZIP 7662468
    • Brewster County, TXModerate · AQI90 64 · ZIP 7983068
    • Montgomery County, TXModerate · AQI90 67 · ZIP 7730167
    • Jefferson County, TXModerate · AQI90 67 · ZIP 7761367
    • Culberson County, TXModerate · AQI90 67 · ZIP 7984767
    • Galveston County, TXModerate · AQI90 68 · ZIP 7751066
    • Hidalgo County, TXModerate · AQI90 69 · ZIP 7850166
    • Brazoria County, TXModerate · AQI90 71 · ZIP 7742265
    • Webb County, TXModerate · AQI90 71 · ZIP 7801965
    • Travis County, TXModerate · AQI90 71 · ZIP 7861765
    • Kleberg County, TXModerate · AQI90 74 · ZIP 7836363
    • Dallas County, TXModerate · AQI90 77 · ZIP 7500162
    • Nueces County, TXModerate · AQI90 76 · ZIP 7833062
    • Cameron County, TXModerate · AQI90 76 · ZIP 7852062
    • Bexar County, TXModerate · AQI90 80 · ZIP 7800260
    • Denton County, TXModerate · AQI90 87 · ZIP 7500757
    • Collin County, TXModerate · AQI90 90 · ZIP 7500255
    • Tarrant County, TXModerate · AQI90 97 · ZIP 7505452
    • Harris County, TXUnhealthy for sensitive groups · AQI90 101 · ZIP 7700250
    • El Paso County, TXUnhealthy for sensitive groups · AQI90 123 · ZIP 7982139
51. 51Nevada9 monitored countiesModerate57

    • Nye County, NVGood · AQI90 45 · ZIP 8900378
    • Lyon County, NVModerate · AQI90 51 · ZIP 8940375
    • Douglas County, NVGood · AQI90 50 · ZIP 8941075
    • Carson City, NVModerate · AQI90 52 · ZIP 8970174
    • Churchill County, NVModerate · AQI90 54 · ZIP 8940673
    • Elko County, NVModerate · AQI90 54 · ZIP 8980173
    • White Pine County, NVModerate · AQI90 64 · ZIP 8930168
    • Washoe County, NVModerate · AQI90 71 · ZIP 8940265
    • Clark County, NVModerate · AQI90 94 · ZIP 8900253
52. 52Arizona13 monitored countiesModerate55

    • Navajo County, AZGood · AQI90 24 · ZIP 8590188
    • Mohave County, AZGood · AQI90 34 · ZIP 8536083
    • Apache County, AZModerate · AQI90 58 · ZIP 8592071
    • La Paz County, AZModerate · AQI90 64 · ZIP 8532568
    • Yavapai County, AZModerate · AQI90 67 · ZIP 8532467
    • Yuma County, AZModerate · AQI90 69 · ZIP 8533666
    • Cochise County, AZModerate · AQI90 71 · ZIP 8560265
    • Coconino County, AZModerate · AQI90 71 · ZIP 8593165
    • Santa Cruz County, AZModerate · AQI90 73 · ZIP 8561164
    • Pima County, AZModerate · AQI90 80 · ZIP 8532160
    • Gila County, AZModerate · AQI90 87 · ZIP 8513557
    • Maricopa County, AZUnhealthy for sensitive groups · AQI90 101 · ZIP 8500350
    • Pinal County, AZModerate · AQI90 100 · ZIP 8511850
53. 53California47 monitored countiesUnhealthy for sensitive groups45

    • Sonoma County, CAGood · AQI90 17 · ZIP 9451592
    • Lake County, CAGood · AQI90 39 · ZIP 9542281
    • Solano County, CAGood · AQI90 42 · ZIP 9451079
    • Marin County, CAGood · AQI90 49 · ZIP 9490176
    • Mono County, CAGood · AQI90 50 · ZIP 9351275
    • San Benito County, CAGood · AQI90 50 · ZIP 9502375
    • Monterey County, CAModerate · AQI90 53 · ZIP 9342674
    • Santa Cruz County, CAModerate · AQI90 53 · ZIP 9500374
    • Tuolumne County, CAModerate · AQI90 54 · ZIP 9530573
    • Humboldt County, CAModerate · AQI90 55 · ZIP 9550173
    • Del Norte County, CAModerate · AQI90 54 · ZIP 9553173
    • Amador County, CAModerate · AQI90 54 · ZIP 9560173
    • El Dorado County, CAModerate · AQI90 54 · ZIP 9561373
    • Glenn County, CAModerate · AQI90 54 · ZIP 9591373
    • Tehama County, CAModerate · AQI90 54 · ZIP 9602173
    • Calaveras County, CAModerate · AQI90 57 · ZIP 9522172
    • Siskiyou County, CAModerate · AQI90 57 · ZIP 9556872
    • Colusa County, CAModerate · AQI90 56 · ZIP 9591272
    • Mendocino County, CAModerate · AQI90 59 · ZIP 9541071
    • Nevada County, CAModerate · AQI90 58 · ZIP 9594571
    • Santa Barbara County, CAModerate · AQI90 61 · ZIP 9301370
    • Butte County, CAModerate · AQI90 61 · ZIP 9591470
    • Shasta County, CAModerate · AQI90 61 · ZIP 9600170
    • Yolo County, CAModerate · AQI90 63 · ZIP 9560569
    • Mariposa County, CAModerate · AQI90 64 · ZIP 9362368
    • Trinity County, CAModerate · AQI90 65 · ZIP 9552768
    • Sutter County, CAModerate · AQI90 64 · ZIP 9565968
    • Ventura County, CAModerate · AQI90 67 · ZIP 9132067
    • San Luis Obispo County, CAModerate · AQI90 67 · ZIP 9340167
    • San Joaquin County, CAModerate · AQI90 67 · ZIP 9520267
    • Placer County, CAModerate · AQI90 71 · ZIP 9560265
    • Sacramento County, CAModerate · AQI90 72 · ZIP 9560864
    • Madera County, CAModerate · AQI90 76 · ZIP 9360162
    • Merced County, CAModerate · AQI90 77 · ZIP 9362062
    • Orange County, CAModerate · AQI90 79 · ZIP 9062061
    • Inyo County, CAModerate · AQI90 81 · ZIP 9232860
    • Stanislaus County, CAModerate · AQI90 80 · ZIP 9523060
    • Kings County, CAModerate · AQI90 85 · ZIP 9320258
    • Plumas County, CAModerate · AQI90 84 · ZIP 9591558
    • San Diego County, CAModerate · AQI90 100 · ZIP 9190150
    • Fresno County, CAModerate · AQI90 100 · ZIP 9321050
    • Tulare County, CAUnhealthy for sensitive groups · AQI90 105 · ZIP 9320148
    • Imperial County, CAUnhealthy for sensitive groups · AQI90 108 · ZIP 9222246
    • Kern County, CAUnhealthy for sensitive groups · AQI90 112 · ZIP 9320344
    • Los Angeles County, CAUnhealthy for sensitive groups · AQI90 147 · ZIP 9000127
    • Riverside County, CAUnhealthy for sensitive groups · AQI90 150 · ZIP 9175225
    • San Bernardino County, CAUnhealthy · AQI90 156 · ZIP 9170122

Informational only, not professional advice. This ranking summarises public EPA monitoring records. It is not a health assessment or a substitute for checking current conditions at a specific address.

county 90th-percentile AQI, averaged across a state's monitored
counties, weighted by county population

state air score = 100 − (weighted average AQI ÷ 2), floored at 0