Exceedance Days: Sept. 14
An Ozone Exceedance = .071 ppm or greater
The EPA Ozone Standard uses the Design Value. Although certainly concerning, exceedance days are not the same thing as 'violating the ozone standard'. The standard uses the 4th highest reading each year and averages it with the 4th highest readings from the two prior years. This 3-year average is called the Design Value. In the table above, the middle columns with dates show this year's 1st through 4th highest daily readings for each monitor. The 4th highest column is the one that counts at year end - the one that is averaged with the 4th highest readings from the two previous years. Each monitor's readings and averages are calculated uniquely and whichever Design Value is the highest becomes the area's Ozone Design Value.
A Violation of the ozone standard = Design Value .071 or greater.
Our 2017 Design Value is .064 ppm as determined by the CENTRAL (and East) monitor. Using the Central monitor's 4th highest values, this is calculated by averaging 2015's 4th high value of .068, 2016's 4th highest value of .062 and 2017's 4th highest reading of .062 ppm (the standard truncates, not rounding up or down).
Does our 2015-2017 Design Value meet the EPA ozone standard? *Yes
*2017 data is preliminary and subject to change as a result of the ODEQ/EPA verification process
Tulsa Area Ozone Alert! Days (2000 - present)
|Year||May||June||July||August||September||TOTAL Alert! Days|
|2012||18th||25th, 26th, 27th, 28th, 29th||10th, 11th, 12th, 13th, 21st, 22nd, 28th||2nd, 3rd, 6th, 7th, 8th, 10th||4th, 5th||21|
|2011||3rd, 15th , 24th, 28th||2nd , 6th , 8th, 9th, 15th, 29th||3rd, 4th, 5th, 17th, 20th, 21st, 24th, 25th, 26th, 27th, 28th||1st, 2nd, 3rd, 13th||25|
|2010||28th||12th, 19th, 23rd , 28th||5|
|2009||24th, 25th, 26th, 27th, 30th||1st, 7th, 11th, 16th||13th, 25th||11|
|2008||18th, 28th, 31st||1st, 2nd, 4th, 5th, 26th||8|
|2007||2nd, 3rd, 14th, 15th, 16th||5|
|2006||25th||12th, 15th, 29th, 30th||1st, 2nd, 17th, 19th, 20th, 21st||24th||12|
|2005||21st, 22nd, 24th, 25th, 26th||30th||1st, 2nd, 4th, 10th||3rd, 4th, 5th||13|
|2004||15th, 21st, 22nd||3|
|2003||2nd, 3rd, 30th||6th, 7th, 23rd, 26th, 27th||8|
|2002||24th, 25th||9th, 10th, 25th||6th, 9th, 31st||8|
|2001||26th||11th, 25th||3rd, 4th, 6th, 7th||14th||8|
|2000||17th||1st, 2nd, 3rd, 4th, 15th, 16th, 23rd, 24th, 25th, 26th||2nd, 3rd, 4th, 8th||15|