Four Highest Eight-Hour Ozone Concentrations in 2020
as of April 4

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	04/03/2020	1000	47	03/08/2020	1000	43	03/20/2020	2300	40	03/21/2020	0100	39
	Ogden Dunes	1	04/03/2020	1000	49	03/08/2020	1100	45	03/21/2020	0100	41	03/20/2020	2100	41
	Michigan City-W. Michigan Blvd	1	04/03/2020	1200	51	03/08/2020	0900	44	02/19/2020	1900	44	03/20/2020	2000	43
	Valparaiso	1	03/08/2020	1000	43	03/20/2020	2000	41	03/17/2020	1100	41	03/01/2020	1000	41
	Gary-IITRI	1	04/03/2020	0900	52	03/17/2020	1100	44	03/08/2020	1000	44	03/20/2020	2200	41
	LaPorte-E. Lincolnway	1	04/03/2020	1100	51	03/08/2020	1000	42	03/23/2020	0900	40	03/04/2020	1000	40
North Central
	South Bend-Shields Dr	1	03/25/2020	1300	40	03/23/2020	1100	39	03/30/2020	1000	37	02/07/2020	1000	37
	Bristol	1	04/03/2020	1200	50	03/08/2020	1300	43	02/29/2020	1000	40	02/28/2020	0900	40
	Potato Creek State Park	1	04/03/2020	1100	52	03/08/2020	1200	48	03/25/2020	1300	45	04/02/2020	1100	43
	Granger-Beckley St	1	04/03/2020	1200	53	03/08/2020	1100	45	04/02/2020	1200	41	03/17/2020	1200	41
North East
	Fort Wayne-Beacon St	1	04/03/2020	1100	50	03/08/2020	1200	44	04/02/2020	1100	43	03/01/2020	1200	42
	Leo HS	1	04/03/2020	1100	48	03/08/2020	1200	44	01/20/2020	1100	43	04/02/2020	1100	42
	Roanoke Elem. School	1	01/01/2020	2100	33	No Data			No Data			No Data
West Central
	Terre Haute-Lafayette Ave	1	04/03/2020	1300	50	03/01/2020	1300	44	03/30/2020	1100	43	03/29/2020	1100	43
	Flora	1	04/03/2020	1100	46	03/08/2020	1100	42	03/02/2020	0100	42	03/01/2020	2200	42
	Sandcut	1	04/03/2020	1200	52	03/08/2020	1300	47	03/01/2020	1300	47	04/02/2020	1000	45
	West Union	1	04/03/2020	1000	50	03/01/2020	1200	46	03/29/2020	1000	45	03/30/2020	1000	44
East Central
	Emporia	1	04/03/2020	1200	45	03/01/2020	2100	45	03/29/2020	1300	44	03/08/2020	1100	43
	Albany	1	04/03/2020	1100	47	03/01/2020	1400	46	03/29/2020	1300	44	03/08/2020	1000	44
	Indpls-Washington Park	1	04/03/2020	1100	50	03/08/2020	1100	45	03/01/2020	2000	44	03/30/2020	1000	43
	Indpls-Harding St	1	04/03/2020	1200	51	04/02/2020	1200	44	03/08/2020	1200	44	03/01/2020	2100	44
	Indpls-Ft. Harrison	1	04/03/2020	1100	49	03/08/2020	1100	44	03/29/2020	1200	43	03/30/2020	1000	42
	Monrovia	1	01/09/2020	1200	38	01/01/2020	1300	36	01/10/2020	0100	35	01/02/2020	0100	34
	Whitestown	1	04/03/2020	1200	52	03/08/2020	1100	46	03/01/2020	1200	46	03/30/2020	1100	43
	Avon	1	04/03/2020	1200	50	03/08/2020	1400	46	03/01/2020	1200	45	03/29/2020	1500	44
	Fairland	1	04/03/2020	1100	46	03/29/2020	1300	44	03/30/2020	1000	42	03/25/2020	1300	42
	Noblesville-191st St	1	04/03/2020	1200	48	03/08/2020	1100	46	03/01/2020	2100	45	03/29/2020	1300	44
	Hope	1	04/03/2020	1100	50	03/01/2020	1500	48	03/25/2020	1300	46	03/08/2020	1100	46
	Indpls - I-70 E	1	04/03/2020	1100	46	03/08/2020	1300	46	03/01/2020	2000	42	03/09/2020	1100	40
	Kokomo - E. Vaile Ave.	1	04/03/2020	0900	45	03/08/2020	1200	45	03/29/2020	1200	42	03/01/2020	2000	42
	Helmsburg	1	04/03/2020	1100	54	03/01/2020	1500	52	03/08/2020	1200	50	03/30/2020	1100	47
South West
	Boonville	1	04/03/2020	0900	53	03/01/2020	1300	46	03/26/2020	1100	44	03/08/2020	1200	44
	Evansville-Buena Vista Rd	1	04/03/2020	1000	53	03/08/2020	1100	48	03/26/2020	1200	47	03/01/2020	1100	47
	Inglefield	1	04/03/2020	1000	52	03/08/2020	1100	47	03/01/2020	1100	46	03/26/2020	1200	45
	St. Philips	1	04/03/2020	1000	54	03/26/2020	1200	48	04/02/2020	1100	45	03/30/2020	0900	45
	Leopold	1	04/03/2020	1100	56	03/01/2020	1200	54	03/08/2020	1200	49	03/26/2020	1300	48
	Dayville	1	04/03/2020	1000	54	03/26/2020	1200	46	04/02/2020	1100	44	03/30/2020	0900	44
	Plummer	1	04/03/2020	1000	52	03/08/2020	1100	46	03/01/2020	1300	46	03/30/2020	1000	45
South East
	New Albany	1	04/03/2020	1100	52	03/01/2020	1500	51	03/30/2020	1100	47	03/26/2020	1500	47
	Charlestown State Park	1	04/03/2020	1300	57	03/01/2020	1300	51	03/30/2020	1100	46	03/08/2020	1200	46
	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.