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Title 40

Displaying title 40, up to date as of 9/08/2026. Title 40 was last amended 9/08/2026.
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  1. Title 40 —Protection of Environment
  2. Chapter I —Environmental Protection Agency
  3. Subchapter C —Air Programs
  4. Part 93 —Determining Conformity of Federal Actions to State or Federal Implementation Plans
  5. Subpart A   View Full Text
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eCFR Content

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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
§ 93.100Purpose.
§ 93.101Definitions.
§ 93.102Applicability.
§ 93.103Priority.
§ 93.104Frequency of conformity determinations.
§ 93.105Consultation.
§ 93.106Content of transportation plans and timeframe of conformity determinations.
§ 93.107Relationship of transportation plan and TIP conformity with the NEPA process.
§ 93.108Fiscal constraints for transportation plans and TIPs.
§ 93.109Criteria and procedures for determining conformity of transportation plans, programs, and projects: General.
§ 93.110Criteria and procedures: Latest planning assumptions.
§ 93.111Criteria and procedures: Latest emissions model.
§ 93.112Criteria and procedures: Consultation.
§ 93.113Criteria and procedures: Timely implementation of TCMs.
§ 93.114Criteria and procedures: Currently conforming transportation plan and TIP.
§ 93.115Criteria and procedures: Projects from a transportation plan and TIP.
§ 93.116Criteria and procedures: Localized CO, PM10, and PM2.5 violations (hot-spots).
§ 93.117Criteria and procedures: Compliance with PM10 and PM2.5 control measures.
§ 93.118Criteria and procedures: Motor vehicle emissions budget.
§ 93.119Criteria and procedures: Interim emissions in areas without motor vehicle emissions budgets.
§ 93.120Consequences of control strategy implementation plan failures.
§ 93.121Requirements for adoption or approval of projects by other recipients of funds designated under title 23 U.S.C. or the Federal Transit Laws.
§ 93.122Procedures for determining regional transportation-related emissions.
§ 93.123Procedures for determining localized CO, PM10, and PM2.5 concentrations (hot-spot analysis).
§ 93.124Using the motor vehicle emissions budget in the applicable implementation plan (or implementation plan submission).
§ 93.125Enforceability of design concept and scope and project-level mitigation and control measures.
§ 93.126Exempt projects.
§ 93.127Projects exempt from regional emissions analyses.
§ 93.128Traffic signal synchronization projects.
§ 93.129Special exemptions from conformity requirements for pilot program areas.
eCFR Content