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The Final 2016 Exceptional Events Rule, Supporting Guidance Documents, Updated FAQs, and Other Rule Implementation Resources

The Exceptional Events Rule, guidance documents, and other implementation resources provided on this page are intended to assist air agencies with the preparation of exceptional events demonstrations. The EPA continues to update and develop documents to facilitate implementation of the 2016 Exceptional Events Rule, including new documents to further assist with the development of demonstrations for specific types of events. We will notify air agencies when we add new implementation resources to this site, and encourage stakeholders to revisit it periodically.

On this page:

Final 2016 Exceptional Events Rule

Guidance Documents and FAQs

Other EPA-Developed Rule Implementation Documents

EPA Exceptional Events Webinar Materials

Online Resources and Tools

EPA provides no endorsement of specific publicly available resources, nor does EPA mandate their use. EPA believes that publicly available tools can provide supporting documentation for one or several of the exceptional event criteria within an air agency exceptional events demonstration, but EPA generally does not believe that links and/or references to these tools constitute a complete demonstration submittal.

  • AirNow (see links for “Fires: Current Conditions” and “Air Quality Basics: Smoke from fires”) EXIT
  • AirNowTech: Website for air quality data management analysis and decision support Exit
  • EPA AirData: Provides access to outdoor air quality data collected from state, local and tribal monitoring agencies across the United States
  • Western Regional Air Partnership: Exceptional Event Data Resource List (primarily smoke- and fire-related)Exit
  • Remote Sensing Information Gateway (RSIG): Allows for quick and easy access to subsets of multi-terabyte environmental datasets, including satellite, modeled, and in-situ sensor dataExit
  • Wildland Fire Air Quality Tools Portal: Provides links to the most recent versions of tools produced by the U.S. Forest Service PNW Research Station’s Pacific Wildland Fire Sciences Laboratory in support of the Wildland Fire Air Quality Response Program and wildland fire operationsEXIT
  • University of Utah MESOWEST: Provides access to current and archived weather observations across the United StatesEXIT

EPA Exceptional Events Contact:
Denise Scott
U.S. EPA, Office of Air Quality Planning and Standards
(919) 541-4280