{"data":{"id":"us/40-cfr-52.1421","jurisdiction":"us","citation":"40 CFR 52.1421","heading":"Classification of regions.","body":"The Nebraska plan was evaluated on the basis of the following classifications:\nAir quality control region Pollutant\nParticulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Photochemical oxidants (hydrocarbons)\nMetropolitan Omaha-Council Bluffs Interstate I II III III III\nLincoln-Beatrice-Fairbury Intrastate II III III III III\nMetropolitan Sioux City Interstate III III III III III\nNebraska Intrastate III III III III III","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER C—AIR PROGRAMS","PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS","Subpart CC—Nebraska"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"3b274211d3f23e1dff312aff26eadc5aa03d5e85fe360f1ac2b28efda08f3934","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-52.1420","next":"us/40-cfr-52.1422"},"notice":"GroundRules: Original legal text. Not legal advice."}