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Title 40

Displaying title 40, up to date as of 7/13/2026. Title 40 was last amended 7/13/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 93Determining Conformity of Federal Actions to State or Federal Implementation Plans93.100 – 93.165
Subpart AConformity to State or Federal Implementation Plans of Transportation Plans, Programs, and Projects Developed, Funded or Approved Under Title 23 U.S.C. or the Federal Transit Laws93.100 – 93.129
Subpart BDetermining Conformity of General Federal Actions to State or Federal Implementation Plans93.150 – 93.165
§ 93.150Prohibition.
§ 93.151State implementation plan (SIP) revision.
§ 93.152Definitions.
§ 93.153Applicability.
§ 93.154Federal agency conformity responsibility.
§ 93.155Reporting requirements.
§ 93.156Public participation.
§ 93.157Reevaluation of conformity.
§ 93.158Criteria for determining conformity of general Federal actions.
§ 93.159Procedures for conformity determinations of general Federal actions.
§ 93.160Mitigation of air quality impacts.
§ 93.161Conformity evaluation for Federal installations with facility-wide emission budgets.
§ 93.162Emissions beyond the time period covered by the SIP.
§ 93.163Timing of offsets and mitigation measures.
§ 93.164Inter-precursor mitigation measures and offsets.
§ 93.165Early emission reduction credit programs at Federal facilities and installation subject to Federal oversight.