Code of Federal Regulations > Title 40 > Chapter I - CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

U.S. Code of Federal Regulations

Regulations most recently checked for updates: Aug 27, 2025

Part 50 [§ 50.1 - § 50.21] - PART 50—NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS

Part 51 [§ 51.1 - § 51.1403] - PART 51—REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS