Four Highest Eight-Hour Ozone Concentrations in 2018
as of October 19

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 2018 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	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	05/28/2018	0900	70	05/27/2018	1000	70	05/25/2018	1000	63	07/11/2018	1000	62
	Ogden Dunes	1	05/27/2018	1000	85	05/28/2018	1000	84	05/25/2018	0900	84	05/26/2018	1000	71
	Michigan City-W. Michigan Blvd	1	05/25/2018	1100	90	07/09/2018	1000	84	05/28/2018	1000	84	05/27/2018	1100	82
	Valparaiso	1	05/28/2018	1100	80	05/26/2018	1100	77	05/27/2018	1000	73	05/25/2018	1000	71
	Gary-IITRI	1	05/25/2018	1000	86	05/28/2018	1000	84	05/27/2018	1100	84	05/26/2018	1100	71
	LaPorte-E. Lincolnway	1	05/28/2018	0900	79	05/27/2018	1000	75	05/26/2018	1100	75	05/25/2018	0900	71
North Central
	South Bend-Shields Dr	1	05/28/2018	1000	80	07/09/2018	1100	76	05/25/2018	1100	74	05/27/2018	1100	73
	Bristol	1	07/09/2018	1100	72	05/25/2018	1100	72	05/28/2018	1000	71	05/27/2018	1100	70
	Potato Creek State Park	1	05/28/2018	1000	75	05/26/2018	1200	73	05/25/2018	1100	72	06/07/2018	1100	69
	Granger-Beckley St	1	07/09/2018	1200	76	05/28/2018	1000	75	05/25/2018	1100	73	06/15/2018	1100	70
North East
	Fort Wayne-Beacon St	1	05/25/2018	1100	73	06/15/2018	1200	71	05/28/2018	1000	70	05/27/2018	1000	69
	Leo HS	1	05/25/2018	1100	77	05/28/2018	1000	73	05/27/2018	1000	73	07/13/2018	1000	72
	Roanoke Elem. School	1	05/28/2018	1000	69	05/25/2018	1100	68	05/27/2018	1100	67	06/15/2018	1200	66
West Central
	Terre Haute-Lafayette Ave	1	07/13/2018	1100	74	06/08/2018	1200	74	05/25/2018	1000	74	05/17/2018	1100	69
	Flora	1	05/25/2018	1100	75	05/27/2018	1000	74	05/28/2018	1100	72	06/15/2018	1100	66
	Sandcut	1	05/25/2018	1000	75	07/13/2018	1100	74	06/08/2018	1100	71	05/17/2018	1000	68
	West Union	1	05/25/2018	0900	71	07/13/2018	1000	69	05/17/2018	1100	68	06/08/2018	0900	66
East Central
	Emporia	1	05/25/2018	1100	81	06/08/2018	1000	76	05/27/2018	1100	74	06/07/2018	1100	72
	Albany	1	05/25/2018	1200	79	06/15/2018	1100	71	05/28/2018	1000	71	05/27/2018	1100	70
	Indpls-Washington Park	1	07/13/2018	1100	80	06/15/2018	1100	77	07/14/2018	1100	73	06/08/2018	1100	72
	Indpls-Harding St	1	07/14/2018	1100	78	05/28/2018	1000	76	05/27/2018	1000	76	06/15/2018	1100	75
	Indpls-Ft. Harrison	1	06/15/2018	1100	80	06/08/2018	1000	78	05/25/2018	1100	78	06/07/2018	1100	76
	Monrovia	1	06/08/2018	1200	70	05/28/2018	1000	70	05/25/2018	1100	67	06/07/2018	1200	66
	Whitestown	1	05/28/2018	1000	74	06/08/2018	1000	73	05/27/2018	1100	73	05/25/2018	1000	73
	Avon	1	06/08/2018	1100	73	06/28/2018	1000	71	05/28/2018	1000	69	05/25/2018	1000	67
	Fairland	1	07/14/2018	1100	74	06/08/2018	1100	73	05/27/2018	1000	73	05/28/2018	1100	72
	Noblesville-191st St	1	06/15/2018	1100	79	07/13/2018	1000	76	05/25/2018	1100	76	06/08/2018	1000	71
	Hope	1	07/14/2018	1000	73	05/25/2018	1100	73	06/07/2018	1200	72	06/08/2018	1100	69
	Indpls - I-70 E	1	07/13/2018	1100	77	06/15/2018	1200	71	05/25/2018	1200	71	05/28/2018	1200	70
	Kokomo - E. Vaile Ave.	1	06/15/2018	1200	73	05/27/2018	1000	73	05/25/2018	1000	73	07/13/2018	1200	72
	Helmsburg	1	06/07/2018	1100	69	05/25/2018	1000	66	06/05/2018	1200	64	05/01/2018	1200	64
South West
	Boonville	1	07/13/2018	1000	78	06/07/2018	1100	75	06/08/2018	1000	73	06/06/2018	1100	70
	Evansville-Buena Vista Rd	1	07/13/2018	1100	83	06/07/2018	1000	75	06/15/2018	1100	73	06/08/2018	0900	68
	Inglefield	1	07/13/2018	1000	76	06/07/2018	0900	73	06/08/2018	0900	68	05/11/2018	1200	66
	St. Philips	1	07/13/2018	1100	70	06/07/2018	0900	70	05/24/2018	1000	68	06/08/2018	0900	67
	Leopold	1	05/01/2018	1000	64	03/15/2018	1200	64	05/11/2018	1000	63	05/08/2018	1200	63
	Dayville	1	06/07/2018	1100	70	06/05/2018	1000	68	06/06/2018	1100	67	06/08/2018	0900	65
	Plummer	1	06/08/2018	1100	79	06/07/2018	1200	78	05/25/2018	1000	72	06/05/2018	1100	66
South East
	New Albany	1	06/16/2018	1100	83	06/15/2018	1100	81	07/14/2018	1200	78	06/07/2018	1100	73
	Charlestown State Park	1	06/08/2018	1000	77	06/15/2018	1100	75	06/07/2018	1100	73	07/14/2018	0900	71
	Brownstown	1	06/07/2018	1100	67	05/28/2018	1000	67	06/08/2018	1100	65	06/05/2018	1100	65
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.