Exceptional Events
An exceptional event is an unusual or naturally occurring event that can affect air quality but is not reasonably controllable. Occasionally, an exceptional event can cause an exceedance of the standards of air quality. The Environmental Protection Agency promulgated the Exceptional Events Rule on March 22, 2007 to treat data influenced by exceptional events that result in violations of the NAAQS. The Rule allows states to "flag" air quality monitoring data as an exceptional event and exclude that data from use in determining a violation of the NAAQS, if the U. S. EPA concurs with the demonstration submitted.
State of Nevada Exceptional Event Demonstrations
