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§ 52.471 Classification of regions.

40 CFR 52.471

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Citation40 CFR 52.471
CorpusDaily eCFR
Displayed edition2026-05-14
Last updated2026-05-14

§ 52.471 Classification of regions.

The District of Columbia plan was evaluated on the basis of the following classifications:

Air quality control regionPollutant
Particulate matterSulfur oxidesNitrogen dioxideCarbon monoxideOzone
National Capital InterstateIIIIIII

[37 FR 10857, May 31, 1972, as amended at 39 FR 16346, May 8, 1974; 46 FR 61263, Dec. 16, 1981]