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Title 40Chapter ISubchapter CPart 51Subpart X → §51.906

Title 40: Protection of Environment
Subpart X—Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard

§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]

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