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Electronic Code of Federal Regulations
Title 40: Protection of Environment
§51.902 Which classification and nonattainment area planning provisions of the CAA shall apply to areas designated nonattainment for the 1997 8-hour NAAQS?
(a) An area designated nonattainment for the 1997 8-hour NAAQS will be classified in accordance with section 181 of the CAA, as interpreted in §51.903(a), for purposes of the 1997 8-hour NAAQS, and will be subject to the requirements of subpart 2 that apply for that classification.
[77 FR 28841, May 14, 2012]