40 CFR § 51.261 - Final compliance schedules.

---
identifier: "/us/cfr/t40/s51.261"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 51.261 - Final compliance schedules."
title_number: 40
title_name: "Protection of Environment"
section_number: "51.261"
section_name: "Final compliance schedules."
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"
---


# 51.261 Final compliance schedules.

(a) Unless EPA grants an extension under subpart R, compliance schedules designed to provide for attainment of a primary standard must—

(1) Provide for compliance with the applicable plan requirements as soon as practicable; or

(2) Provide for compliance no later than the date specified for attainment of the primary standard under;

(b) Unless EPA grants an extension under subpart R, compliance schedules designed to provide for attainment of a secondary standard must—

(1) Provide for compliance with the applicable plan requirements in a reasonable time; or

(2) Provide for compliance no later than the date specified for the attainment of the secondary standard under § 51.110(c).