CFR›Title 40›Chapter I›Part 51›Subpart L ContainsSections 51.230–51.232CorpusDaily eCFRDisplayed edition2026-05-18Last updated2026-05-18 Subpart L—Legal Authority Sections 51.230 § 51.230 Requirements for all plans. 51.231 § 51.231 Identification of legal authority. 51.232 § 51.232 Assignment of legal authority to local agencies. Source51 FR 40673, Nov. 7, 1986, unless otherwise noted. Previous X Subpart X—Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard Next CC Subpart CC—Provisions for Implementation of the 2015 Ozone National Ambient Air Quality Standards