--- kind: "section" citation: "40 C.F.R. § 52.1920" title: "40" number: "52.1920" heading: "Identification of plan." url: "https://uscodex.org/cfr/40/52.1920" --- # §52.1920. Identification of plan. - (a) **Purpose and scope.** This section sets forth the applicable State Implementation Plan (SIP) for Oklahoma under section 110 of the Clean Air Act, 42 U.S.C. [7410](/usc/42/7410.md), and [40](/usc/42/40.md) CFR [part 51](/cfr/40/part51.md) to meet national ambient air quality standards. - (b) **Incorporation by reference.** - (1) Material listed in paragraphs [(c)](#c) and [(d)](#d) of this section with an EPA approval date on or before June 1, 2000, was approved for incorporation by reference by the Director of the Federal Register in accordance with 5 U.S.C. [552(a)](/usc/5/552.md?p=a) and [1](/usc/5/1.md) CFR [part 51](/cfr/40/part51.md). Material is incorporated as it exists on the date of the approval, and notice of any change in the material will be published in the Federal Register. Entries in paragraphs (c) and [(d)](#d) of this section with EPA approval dates after June 1, 2000, will be incorporated by reference in the next update to the SIP compilation. - (2) EPA Region 6 certifies that the rules/regulations provided by EPA in the SIP compilation at the addresses in [paragraph (b)(3)](#b-3) of this section are an exact duplicate of the officially promulgated State rules/regulations which have been approved as part of the State Implementation Plan as of June 1, 2000. - (3) Copies of the materials incorporated by reference may be inspected at https://www.epa.gov/sips-ok or the Environmental Protection Agency, Region 6, 1201 Elm Street, Suite 500, Dallas, Texas 75270-2102. If you wish to obtain material from the EPA Regional Office, please call (800) 887-6063 or (214) 665-2760. - (c) **EPA approved regulations.** - (d) **EPA approved state source-specific requirements.** - (e) **EPA approved nonregulatory provisions and quasi-regulatory measures.** ## Notes ### Amendments [65 FR 47328, Aug. 2, 2000; 65 FR 52476, 52477, Aug. 29, 2000, as amended at 70 FR 48080, Aug. 16, 2005; 70 FR 48647, Aug. 19, 2005; 70 FR 53275, Sept. 7, 2005; 73 FR 79404, Dec. 29, 2008; 75 FR 72701, Nov. 26, 2010; 76 FR 81757, Dec. 28, 2011; 76 FR 81839, Dec. 29, 2011; 77 FR 3934, Jan. 26, 2012; 79 FR 12953, Mar. 7, 2014; 80 FR 67650, Dec. 3, 2015; 81 FR 349, Jan. 5, 2016; 81 FR 66535, Sept. 28, 2016; 81 FR 89010, Dec. 9, 2016; 82 FR 22284, May 15, 2017; 82 FR 27122, June 14, 2017; 83 FR 31331, July 5, 2018; 83 FR 44238, Aug. 30, 2018; 84 FR 977, Feb. 1, 2019; 84 FR 30919, June 28, 2019; 84 FR 44228, Aug. 23, 2019; 84 FR 37585, Aug. 1, 2019; 85 FR 17503, Mar. 30, 2020; 85 FR 20181, Apr. 10, 2020; 85 FR 28494, May 13, 2020; 87 FR 45656, July 29, 2022; 87 FR 50266, Aug. 16, 2022; 88 FR 24920, Apr. 25, 2023; 88 FR 25285, Apr. 26, 2023; 88 FR 89592, Dec. 28, 2023; 90 FR 56008, Dec. 5, 2025; 91 FR 3048, Jan. 26, 2026; 91 FR 40414, July 2, 2026] ### Authority Authority: 42 U.S.C. 7401 et seq. ### Amendments [40 FR 5521, Feb. 6, 1975] ### Amendments [65 FR 47328, Aug. 2, 2000; 65 FR 52476, 52477, Aug. 29, 2000, as amended at 70 FR 48080, Aug. 16, 2005; 70 FR 48647, Aug. 19, 2005; 70 FR 53275, Sept. 7, 2005; 73 FR 79404, Dec. 29, 2008; 75 FR 72701, Nov. 26, 2010; 76 FR 81757, Dec. 28, 2011; 76 FR 81839, Dec. 29, 2011; 77 FR 3934, Jan. 26, 2012; 79 FR 12953, Mar. 7, 2014; 80 FR 67650, Dec. 3, 2015; 81 FR 349, Jan. 5, 2016; 81 FR 66535, Sept. 28, 2016; 81 FR 89010, Dec. 9, 2016; 82 FR 22284, May 15, 2017; 82 FR 27122, June 14, 2017; 83 FR 31331, July 5, 2018; 83 FR 44238, Aug. 30, 2018; 84 FR 977, Feb. 1, 2019; 84 FR 30919, June 28, 2019; 84 FR 44228, Aug. 23, 2019; 84 FR 37585, Aug. 1, 2019; 85 FR 17503, Mar. 30, 2020; 85 FR 20181, Apr. 10, 2020; 85 FR 28494, May 13, 2020; 87 FR 45656, July 29, 2022; 87 FR 50266, Aug. 16, 2022; 88 FR 24920, Apr. 25, 2023; 88 FR 25285, Apr. 26, 2023; 88 FR 89592, Dec. 28, 2023; 90 FR 56008, Dec. 5, 2025; 91 FR 3048, Jan. 26, 2026; 91 FR 40414, July 2, 2026]