Amends the Clean Air Act to prohibit any national ambient air quality standard prescribed after January 1, 2006, for particulate matter other than fine particulate matter from applying to any ambient mix of particulate matter the majority of which is rural windblown dust and soils and particulate matter generated by agricultural sources.
Defines "agricultural sources" to mean crop production and animal production within the meaning of the U.S. Bureau of Census North American Industry Classification System.