Regulations last checked for updates: May 14, 2024

Title 40 - Protection of Environment last revised: May 10, 2024
§ 51.1103 - Application of classification and attainment date provisions in CAA section 181 to areas subject to § 51.1102.

(a) In accordance with CAA section 181(a)(1), each area designated nonattainment for the 2008 ozone NAAQS shall be classified by operation of law at the time of designation. The classification shall be based on the 8-hour design value for the area at the time of designation, in accordance with Table 1 below. A state may request a higher or lower classification as provided in paragraphs (b) and (c) of this section. For each area classified under this section, the attainment date for the 2008 NAAQS shall be as expeditious as practicable but not later than the date provided in Table 1 as follows:

Table 1—Classifications and Attainment Dates for 2008 8-Hour Ozone NAAQS (0.075 PPM) for Areas Subject to CFR Section 51.1102

Area class 8-hour design value (ppm ozone) Primary standard attainment date (years after the
effective date of designation for 2008 primary NAAQS)
Marginalfrom0.0763
up to*0.086
Moderatefrom0.0866
up to*0.100
Seriousfrom0.1009
up to*0.113
Severe-15from0.11315
up to*0.119
Severe-17from0.11917
up to*0.175
Extremeequal to or above0.17520

* But not including

(b) A state may request, and the Administrator must approve, a higher classification for any reason in accordance with CAA section 181(b)(3).

(c) A state may request, and the Administrator may in the Administrator's discretion approve, a higher or lower classification in accordance with CAA section 181(a)(4).

(d) The following nonattainment areas are reclassified for the 2008 ozone NAAQS as follows: Serious—Ventura County, CA; Severe—Los Angeles-San Bernardino Counties (West Mojave Desert), Riverside County (Coachella Valley), and Sacramento Metro, CA; Extreme—Los Angeles-South Coast Air Basin, and San Joaquin Valley, CA.

[77 FR 30170, May 21, 2012, as amended at 80 FR 12313, Mar. 6, 2015]
source: 36 FR 22398, Nov. 25, 1971, unless otherwise noted.
cite as: 40 CFR 51.1103