Four Highest Eight-Hour Ozone Concentrations in 2020
as of January 21

Use this form to retrieve the four highest eight-hour ozone concentration averages from data collected at IDEM monitoring sites beginning December 14, 2005 through today. Although this is our most current data, it is not considered official until it has been certified by our technical staff. This information is updated hourly. All times shown are in Local Standard Time.

The table below lists the four highest daily maximum eight-hour ozone concentrations measured in 2020 in each community where the IDEM measures ozone. Concentrations that are rated Moderate or higher are color-highlighted based on the EPA-defined Air Quality Index colors. (See Interpreting the AQI.) The fourth-highest average is in bold black (unless it is highlighted). All ozone measurements are in parts per billion. Times are shown in 24-hour format and correspond to the beginning of the eight hour average.

Use the selection boxes below to customize this report. You may select a different year or a different report format. If you want to cut and paste data from this web page into another application, such as a spreadsheet, select the comma-delimited format. Click on the Generate Report button once you have made your selections.

Year	Report Format
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020	Tabular (Web Formatted) Comma-Delimited
Highlight with AQI colors

Area	Monitoring Site	POC	Highest			Second Highest			Third Highest			Fourth Highest
			Date	Time	Value	Date	Time	Value	Date	Time	Value	Date	Time	Value
North West
	Hammond-141st St	1	01/11/2020	1200	32	01/09/2020	1100	30	01/04/2020	1300	30	01/01/2020	1700	29
	Ogden Dunes	1	01/20/2020	2000	34	01/11/2020	1300	34	01/09/2020	1300	31	01/08/2020	0200	31
	Michigan City-W. Michigan Blvd	1	01/20/2020	1900	41	01/11/2020	1300	37	01/04/2020	1600	37	01/19/2020	1600	36
	Valparaiso	1	01/11/2020	1200	31	01/09/2020	1300	31	01/01/2020	1600	29	01/08/2020	0100	28
	Gary-IITRI	1	01/11/2020	1200	35	01/09/2020	1700	32	01/01/2020	2000	31	01/16/2020	1800	29
	LaPorte-E. Lincolnway	1	01/20/2020	0900	32	01/04/2020	1600	32	01/09/2020	1600	31	01/08/2020	0100	31
North Central
	South Bend-Shields Dr	1	01/09/2020	1700	33	01/04/2020	1800	32	01/01/2020	2000	32	01/21/2020	0800	31
	Bristol	1	01/04/2020	2000	34	01/20/2020	1100	32	01/09/2020	1600	32	01/08/2020	0100	31
	Potato Creek State Park	1	01/20/2020	1100	38	01/09/2020	1700	34	01/04/2020	1500	33	01/21/2020	0800	32
	Granger-Beckley St	1	01/04/2020	1900	34	01/20/2020	1200	31	01/09/2020	1800	31	01/08/2020	0100	31
North East
	Fort Wayne-Beacon St	1	01/20/2020	1100	40	01/21/2020	0700	35	01/04/2020	2000	33	01/09/2020	1700	32
	Leo HS	1	01/20/2020	1100	43	01/21/2020	0800	39	01/04/2020	2200	37	01/05/2020	0100	35
	Roanoke Elem. School	1	01/01/2020	2100	33	No Data			No Data			No Data
West Central
	Terre Haute-Lafayette Ave	1	01/09/2020	1100	32	01/01/2020	1300	31	01/05/2020	1200	29	01/10/2020	0100	28
	Flora	1	01/09/2020	1400	32	01/04/2020	1800	31	01/01/2020	1400	31	01/10/2020	0100	30
	Sandcut	1	01/09/2020	1100	35	01/01/2020	1300	34	01/10/2020	0100	32	01/05/2020	1300	32
	West Union	1	01/09/2020	1000	35	01/01/2020	1100	33	01/10/2020	0100	32	01/05/2020	1000	31
East Central
	Emporia	1	01/20/2020	1700	34	01/10/2020	0300	34	01/09/2020	1300	34	01/01/2020	1300	33
	Albany	1	01/20/2020	1400	36	01/10/2020	0200	34	01/21/2020	0100	33	01/09/2020	1300	33
	Indpls-Washington Park	1	01/20/2020	1300	33	01/10/2020	0200	33	01/09/2020	1300	33	01/01/2020	1200	33
	Indpls-Harding St	1	01/01/2020	1200	32	01/10/2020	1800	31	01/09/2020	1300	31	01/05/2020	0900	29
	Indpls-Ft. Harrison	1	01/01/2020	1300	33	01/20/2020	1300	32	01/09/2020	1400	32	01/05/2020	1200	31
	Monrovia	1	01/09/2020	1200	38	01/01/2020	1300	36	01/10/2020	0100	35	01/02/2020	0100	34
	Whitestown	1	01/09/2020	1300	33	01/01/2020	2100	33	01/20/2020	1300	30	01/05/2020	1100	30
	Avon	1	01/09/2020	1200	36	01/01/2020	1600	34	01/02/2020	0100	32	01/10/2020	0100	31
	Fairland	1	01/09/2020	1300	36	01/10/2020	0300	33	01/01/2020	1100	33	01/21/2020	0800	32
	Noblesville-191st St	1	01/20/2020	1300	32	01/09/2020	1300	32	01/01/2020	1200	32	01/04/2020	2100	31
	Hope	1	01/21/2020	0500	37	01/09/2020	1500	36	01/20/2020	2000	35	01/10/2020	0100	35
	Indpls - I-70 E	1	01/09/2020	1300	31	01/01/2020	1300	31	01/10/2020	0200	30	01/05/2020	0900	27
	Kokomo - E. Vaile Ave.	1	01/10/2020	0100	31	01/09/2020	1600	31	01/04/2020	2000	31	01/01/2020	2100	31
	Helmsburg	1	01/09/2020	1300	39	01/10/2020	0400	37	01/01/2020	1300	36	01/08/2020	0900	34
South West
	Boonville	1	01/09/2020	1200	37	01/01/2020	1100	36	01/10/2020	0800	32	01/08/2020	0800	32
	Evansville-Buena Vista Rd	1	01/09/2020	1100	36	01/01/2020	1100	36	01/08/2020	0800	33	01/05/2020	1100	33
	Inglefield	1	01/09/2020	1000	36	01/01/2020	1100	35	01/08/2020	0900	32	01/05/2020	1100	32
	St. Philips	1	01/09/2020	1200	38	01/01/2020	1100	36	01/10/2020	1100	33	01/08/2020	0900	31
	Leopold	1	01/09/2020	1800	40	01/10/2020	0100	38	01/01/2020	1200	38	01/21/2020	0700	35
	Dayville	1	01/01/2020	1000	35	01/10/2020	0900	33	01/06/2020	0900	32	01/05/2020	1100	32
	Plummer	1	01/09/2020	1200	37	01/10/2020	0400	36	01/01/2020	1300	35	01/08/2020	1000	32
South East
	New Albany	1	01/08/2020	0900	34	01/21/2020	0700	33	01/07/2020	1100	32	01/01/2020	1000	32
	Charlestown State Park	1	01/09/2020	1900	37	01/08/2020	1100	37	01/10/2020	0100	35	01/01/2020	1100	34
	Brownstown	1	01/01/2020	1100	34	No Data			No Data			No Data
POC (Parameter Occurrence Code): a code used to correctly separate data from multiple instruments at one site.

Interpreting the AQI

Each NAAQS pollutant has a separate AQI scale, with an AQI rating of 100 corresponding to the concentration of the Federal Standard for that pollutant. Additional information about the AQI and how it can be used is available from the EPA's AirNow web site.

Place your mouse pointer over the scale displayed above to view information about the Air Quality Index, and each of the rating levels.

The actual index calculation is different for each parameter measured and is specified by the EPA. The following table shows the various breakpoints used in calculating the AQI.

AQI Breakpoint Definitions
AQI Range	1hr Ozone in ppm	8hr Ozone in ppm
0 - 50	Not Defined	0 - 0.054
51 - 100	Not Defined	0.055 - 0.070
101 - 150	0.125 - 0.164	0.071 - 0.085
151 - 200	0.165 - 0.204	0.086 - 0.105
201 - 300	0.205 - 0.404	0.106 - 0.200
301 - 400	0.405 - 0.504	0.201 - 0.2011
401 - 500	0.505 - 0.604	Not Defined
500+	Not Defined	Not Defined

• The AQI for ozone is based on either the peak eight-hour running average since midnight OR the peak one-hour measurement since midnight.

PLEASE NOTE: This data has not been verified by the IDEM and may change. This is the most current data, but it is not official until it has been certified by our technical staff. Data is collected from IDEM ambient monitoring sites and may include data collected by other outside agencies. This data is updated hourly. All times shown are in local standard time unless otherwise indicated.