Division of Air Quality
Air Quality Exceptional Events Program
Air quality exceptional events are unusual or naturally occurring events that can affect air quality but are not reasonably controllable using techniques tribal, state or local air agencies may implement in order to attain and maintain the National Ambient Air Quality Standards. Exceptional events are events for which the normal planning and regulatory process established by the Clean Air Act (CAA) is not appropriate.
One type of exceptional event is a natural event. EPA defines a “natural event” as an event in which human activity plays little or no direct causal role to the event in question. For example, a natural event could include such things as high winds, wild fires, and seismic/volcanic activity. Federal regulations (40 Code of Federal Regulations Part 50.14 (b)(2) also allow states to exclude data from regulatory determinations on a case-by-case basis for monitoring stations whose exceedances or violations are caused by emissions from fireworks displays.
- View the EPA’s Exceptional Events rule.
Exceptional Events Documentation
The following is a list of exceptional events documents that have been submitted to EPA since 2008.
Note: The following content is archived, and is being kept for reference, research, or recordkeeping.
High Wind Events
- April 14, 2015
- April 27, 2010
- March 30, 2010
- March 4, 2009
- May 20, 2008
- April 29, 2008
- April 19, 2008
- April 15, 2008
- EPA Comments and DAQ Responses
Wildfire Events
- September 5-7, 2017 (EPA Concurrence for Smithfield Only)
- August 6 – 7, 2017 (EPA Concurrence)
- August, 2015
- July 9, 2013
- August, 2012
- Appendix
- September, 2012
- August, 2009
- June 26, 2008
Fireworks Events
- July 4, 2017
- July 4, 2013
- July 4, 2012
- July 4, 2011
- July 4, 2010
- July 4, 2009 (EPA Concurrence)
- July 4, 2008 (EPA Concurrence)