This rule establishes air quality designations for all areas in the United States for the 2010 Primary Nitrogen Dioxide (NO<INF>2</INF>) National Ambient Air Quality Standards (NAAQS). Based on air quality monitoring data, the EPA is issuing this rule to designate all areas of the country as "unclassifiable/attainment" for the 2010 NO<INF>2</INF> NAAQS. The EPA is designating areas as "unclassifiable/attainment" to mean that available information does not indicate that the air quality in these areas exceeds the 2010 NO<INF>2</INF> NAAQS.