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U.S. Code of Federal Regulations
Regulations most recently checked for updates: Aug 27, 2025
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Title 40
Chapter I
Part 81
Subpart E - Subpart E—Identification of Interstate Transport Regions
§ 81.455 - Scope.
§ 81.457 - Ozone Transport Region.
Appendix Appendix A - Appendix A to Part 81—Air Quality Control Regions (AQCR's)
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