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Electronic Code of Federal Regulations
Title 40: Protection of Environment
§51.906 Redesignation to nonattainment following initial designations for the 8-hour NAAQS.
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.
[70 FR 71700, Nov. 29, 2005]