CFR›Title 40›Chapter I›Part 66›Subpart A ContainsSections 66.1–66.6CorpusDaily eCFRDisplayed edition2026-04-15Last updated2026-04-15 Subpart A—Purpose and Scope Sections 66.1 § 66.1 Applicability and effective date. 66.2 § 66.2 Program description. 66.3 § 66.3 Definitions. 66.4 § 66.4 Limitation on review of regulations. 66.5 § 66.5 Savings clause. 66.6 § 66.6 Effect of litigation; time limits. Next Appendix A to Part 66 Appendix A to Part 66—Technical Support Document