40 CFR § 51.1401 - Applicability of part 51.

---
identifier: "/us/cfr/t40/s51.1401"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 51.1401 - Applicability of part 51."
title_number: 40
title_name: "Protection of Environment"
section_number: "51.1401"
section_name: "Applicability of part 51."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "51"
part_name: "REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "23 U.S.C. 101; 42 U.S.C. 7401-7671q."
regulatory_source: "36 FR 22398, Nov. 25, 1971, unless otherwise noted."
cfr_part: "51"
---


# 51.1401 Applicability of part 51.

The provisions in subparts A through Y, AA, and CC of this part apply to reclassified nonattainment areas for purposes of the ozone NAAQS to the extent they are not inconsistent with the provisions of this subpart.