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§ 52.171 Classification of regions.

40 CFR 52.171

Citation40 CFR 52.171
CorpusDaily eCFR
Displayed edition2026-09-09
Last updated2026-09-09

§ 52.171 Classification of regions.

The Arkansas plan was evaluated on the basis of the following classifications:

Air quality control regionPollutant
Particulate matterSulfur oxidesNitrogen dioxideCarbon monoxideOzone
Central Arkansas IntrastateIIIIIIIIIIIIII
Metropolitan Fort Smith InterstateIIIIIIIIIIIIII
Metropolitan Memphis InterstateIIIIIIIIIII
Monroe (Louisiana)-El Dorado (Arkansas) InterstateIIIIIIIIIIIIII
Northeast Arkansas IntrastateIIIIIIIIIIIIIII
Northwest Arkansas IntrastateIIIIIIIIIIIIIII
Shreveport-Texarkana-Tyler InterstateIIIIIIIIIIIIII

[37 FR 10850, May 31, 1972, as amended at 39 FR 16346, May 8, 1974; 45 FR 6571, Jan. 29, 1980]