40 CFR § 52.424 - Conditional approval.

---
identifier: "/us/cfr/t40/s52.424"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 52.424 - Conditional approval."
title_number: 40
title_name: "Protection of Environment"
section_number: "52.424"
section_name: "Conditional approval."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "52"
part_name: "APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7401"
cfr_part: "52"
---


# 52.424 Conditional approval.

(a)-(d) [Reserved]

[62 FR 27197, May 19, 1997, as amended at 63 FR 1368, Jan. 9, 1998; 63 FR 16435, Apr. 3, 1998; 64 FR 32189, June 16, 1999; 64 FR 52660, Sept. 30, 1999; 64 FR 55141, Oct. 12, 1999; 66 FR 9211, Feb. 7, 2001; 66 FR 32234, June 14, 2001]