{"data":{"id":"us/40-cfr-51.906","jurisdiction":"us","citation":"40 CFR 51.906","heading":"Redesignation to nonattainment following initial designations for the 8-hour NAAQS.","body":"For any area that is initially designated attainment or unclassifiable for the 8-hour NAAQS and that is subsequently redesignated to nonattainment for the 8-hour ozone NAAQS, any absolute, fixed date applicable in connection with the requirements of this part is extended by a period of time equal to the length of time between the effective date of the initial designation for the 8-hour NAAQS and the effective date of redesignation, except as otherwise provided in this subpart.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER C—AIR PROGRAMS","PART 51—REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS","Subpart X—Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard"],"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":"3a7b21f34a26e62a956caba9a79f3b57cee13df98499cab135959e0cf0a419f5","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-51.905","next":"us/40-cfr-51.907"},"notice":"GroundRules: Original legal text. Not legal advice."}