Air-quality SIP machinery behind AF air permits. 185 sections, full current text (eCFR edition 2026-07-15), each cross-linked to the AF pubs that cite it.
| Section | Title | AF citations |
|---|---|---|
| 51.1 | Who is responsible for actions described in this subpart? | — |
| 51.5 | What tools are available to help prepare and report emissions data? | — |
| 51.15 | What data does my state need to report to EPA? | — |
| 51.20 | What are the emission thresholds that separate point and nonpoint sources? | — |
| 51.25 | What geographic area must my state's inventory cover? | — |
| 51.30 | When does my state report which emissions data to EPA? | — |
| 51.35 | How can my state equalize the emission inventory effort from year to year? | — |
| 51.40 | In what form and format should my state report the data to EPA? | — |
| 51.45 | Where should my state report the data? | — |
| 51.50 | What definitions apply to this subpart? | — |
| 51.100 | Definitions. | — |
| 51.101 | Stipulations. | — |
| 51.102 | Public hearings. | — |
| 51.103 | Submission of plans, preliminary review of plans. | — |
| 51.104 | Revisions. | — |
| 51.105 | Approval of plans. | — |
| 51.110 | Attainment and maintenance of national standards. | — |
| 51.111 | Description of control measures. | — |
| 51.112 | Demonstration of adequacy. | — |
| 51.114 | Emissions data and projections. | — |
| 51.115 | Air quality data and projections. | — |
| 51.116 | Data availability. | — |
| 51.117 | Additional provisions for lead. | — |
| 51.118 | Stack height provisions. | — |
| 51.119 | Intermittent control systems. | — |
| 51.120 | Requirements for State Implementation Plan revisions relating to new motor vehicles. | — |
| 51.121 | Findings and requirements for submission of State implementation plan revisions relating to emissions of nitrogen oxides. | — |
| 51.122 | Emissions reporting requirements for SIP revisions relating to budgets for NOX emissions. | — |
| 51.123 | Findings and requirements for submission of State implementation plan revisions relating to emissions of oxides of nitrogen pursuant to the Clean Air Interstate Rule. | — |
| 51.124 | Findings and requirements for submission of State implementation plan revisions relating to emissions of sulfur dioxide pursuant to the Clean Air Interstate Rule. | — |
| 51.126 | Determination of widespread use of ORVR and waiver of CAA section 182(b)(3) Stage II gasoline vapor recovery requirements. | — |
| 51.150 | Classification of regions for episode plans. | — |
| 51.151 | Significant harm levels. | — |
| 51.152 | Contingency plans. | — |
| 51.153 | Reevaluation of episode plans. | — |
| 51.160 | Legally enforceable procedures. | — |
| 51.161 | Public availability of information. | — |
| 51.162 | Identification of responsible agency. | — |
| 51.163 | Administrative procedures. | — |
| 51.164 | Stack height procedures. | — |
| 51.165 | Permit requirements. | 3 × 1 pubs |
| 51.166 | Prevention of significant deterioration of air quality. | 1 × 1 pubs |
| 51.190 | Ambient air quality monitoring requirements. | — |
| 51.210 | General. | — |
| 51.211 | Emission reports and recordkeeping. | — |
| 51.212 | Testing, inspection, enforcement, and complaints. | — |
| 51.213 | Transportation control measures. | — |
| 51.214 | Continuous emission monitoring. | — |
| 51.230 | Requirements for all plans. | — |
| 51.231 | Identification of legal authority. | — |
| 51.232 | Assignment of legal authority to local agencies. | — |
| 51.240 | General plan requirements. | — |
| 51.241 | Nonattainment areas for carbon monoxide and ozone. | — |
| 51.260 | Legally enforceable compliance schedules. | — |
| 51.261 | Final compliance schedules. | — |
| 51.262 | Extension beyond one year. | — |
| 51.280 | Resources. | — |
| 51.281 | Copies of rules and regulations. | — |
| 51.285 | Public notification. | — |
| 51.286 | Electronic reporting. | — |
| 51.300 | Purpose and applicability. | — |
| 51.301 | Definitions. | — |
| 51.302 | Reasonably attributable visibility impairment. | — |
| 51.303 | Exemptions from control. | — |
| 51.304 | Identification of integral vistas. | — |
| 51.305 | Monitoring for reasonably attributable visibility impairment. | — |
| 51.307 | New source review. | — |
| 51.308 | Regional haze program requirements. | — |
| 51.309 | Requirements related to the Grand Canyon Visibility Transport Commission. | — |
| 51.320 | Annual air quality data report. | — |
| 51.321 | Annual source emissions and State action report. | — |
| 51.322 | Sources subject to emissions reporting. | — |
| 51.323 | Reportable emissions data and information. | — |
| 51.324 | Progress in plan enforcement. | — |
| 51.326 | Reportable revisions. | — |
| 51.327 | Enforcement orders and other State actions. | — |
| 51.341 | Request for 18-month extension. | — |
| 51.350 | Applicability. | — |
| 51.351 | Enhanced I/M performance standard. | — |
| 51.352 | Basic I/M performance standard. | — |
| 51.353 | Network type and program evaluation. | — |
| 51.354 | Adequate tools and resources. | — |
| 51.355 | Test frequency and convenience. | — |
| 51.356 | Vehicle coverage. | — |
| 51.357 | Test procedures and standards. | — |
| 51.358 | Test equipment. | — |
| 51.359 | Quality control. | — |
| 51.360 | Waivers and compliance via diagnostic inspection. | — |
| 51.361 | Motorist compliance enforcement. | — |
| 51.362 | Motorist compliance enforcement program oversight. | — |
| 51.363 | Quality assurance. | — |
| 51.364 | Enforcement against contractors, stations and inspectors. | — |
| 51.365 | Data collection. | — |
| 51.366 | Data analysis and reporting. | — |
| 51.367 | Inspector training and licensing or certification. | — |
| 51.368 | Public information and consumer protection. | — |
| 51.369 | Improving repair effectiveness. | — |
| 51.370 | Compliance with recall notices. | — |
| 51.371 | On-road testing. | — |
| 51.372 | State Implementation Plan submissions. | — |
| 51.373 | Implementation deadlines. | — |
| 51.390 | Implementation plan revision. | — |
| 51.490 | Applicability. | — |
| 51.491 | Definitions. | — |
| 51.492 | State program election and submittal. | — |
| 51.493 | State program requirements. | — |
| 51.494 | Use of program revenues. | — |
| 51.851 | State implementation plan (SIP) or Tribal implementation plan (TIP) revision. | — |
| 51.900 | Definitions. | — |
| 51.901 | Applicability of part 51. | — |
| 51.902 | Which classification and nonattainment area planning provisions of the CAA shall apply to areas designated nonattainment for the 1997 8-hour NAAQS? | — |
| 51.903 | How do the classification and attainment date provisions in section 181 of subpart 2 of the CAA apply to areas subject to § 51.902(a)? | — |
| 51.904 | How do the classification and attainment date provisions in section 172(a) of subpart 1 of the CAA apply to areas subject to § 51.902(b)? | — |
| 51.905 | How do areas transition from the 1-hour NAAQS to the 1997 8-hour NAAQS and what are the anti-backsliding provisions? | — |
| 51.906 | Redesignation to nonattainment following initial designations for the 8-hour NAAQS. | — |
| 51.907 | For an area that fails to attain the 8-hour NAAQS by its attainment date, how does EPA interpret sections 172(a)(2)(C)(ii) and 181(a)(5)(B) of the CAA? | — |
| 51.908 | What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone NAAQS? | — |
| 51.910 | What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply for areas designated nonattainment for the 8-hour ozone NAAQS? | — |
| 51.912 | What requirements apply for reasonably available control technology (RACT) and reasonably available control measures (RACM) under the 8-hour NAAQS? | — |
| 51.913 | How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS? | — |
| 51.914 | What new source review requirements apply for 8-hour ozone nonattainment areas? | — |
| 51.915 | What emissions inventory requirements apply under the 8-hour NAAQS? | — |
| 51.916 | What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? | — |
| 51.917 | What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area? | — |
| 51.918 | Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? | — |
| 51.919 | Applicability. | — |
| 51.930 | Mitigation of Exceptional Events. | — |
| 51.1000 | Definitions. | — |
| 51.1001 | Applicability of part 51. | — |
| 51.1002 | Classifications and reclassifications. | — |
| 51.1003 | Attainment plan due dates and submission requirements. | — |
| 51.1004 | Attainment dates. | — |
| 51.1005 | Attainment date extensions. | — |
| 51.1006 | Optional PM2.5 precursor demonstrations | — |
| 51.1008 | Emissions inventory requirements. | — |
| 51.1009 | Moderate area attainment plan control strategy requirements. | — |
| 51.1010 | Serious area attainment plan control strategy requirements. | — |
| 51.1011 | Attainment demonstration and modeling requirements. | — |
| 51.1012 | Reasonable further progress (RFP) requirements. | — |
| 51.1013 | Quantitative milestone requirements. | — |
| 51.1014 | Contingency measure requirements. | — |
| 51.1015 | Clean data requirements. | — |
| 51.1016 | Continued applicability of the FIP and SIP requirements pertaining to interstate transport under CAA section 110(a)(2)(D)(i) and (ii) after revocation of the 1997 primary annual PM2.5 NAAQS. | — |
| 51.1100 | Definitions. | — |
| 51.1101 | Applicability of part 51. | — |
| 51.1102 | Classification and nonattainment area planning provisions. | — |
| 51.1103 | Application of classification and attainment date provisions in CAA section 181 to areas subject to § 51.1102. | — |
| 51.1105 | Transition from the 1997 ozone NAAQS to the 2008 ozone NAAQS and anti-backsliding. | — |
| 51.1106 | Redesignation to nonattainment following initial designations. | — |
| 51.1107 | Determining eligibility for 1-year attainment date extensions for the 2008 ozone NAAQS under CAA section 181(a)(5). | — |
| 51.1108 | Modeling and attainment demonstration requirements. | — |
| 51.1110 | Requirements for reasonable further progress (RFP). | — |
| 51.1112 | Requirements for reasonably available control technology (RACT) and reasonably available control measures (RACM). | — |
| 51.1113 | Section 182(f) NOX exemption provisions. | — |
| 51.1114 | New source review requirements. | — |
| 51.1115 | Emissions inventory requirements. | — |
| 51.1116 | Requirements for an Ozone Transport Region. | — |
| 51.1117 | Fee programs for Severe and Extreme nonattainment areas that fail to attain. | — |
| 51.1118 | Suspension of SIP planning requirements in nonattainment areas that have air quality data that meet an ozone NAAQS. | — |
| 51.1119 | Applicability. | — |
| 51.1200 | Definitions. | — |
| 51.1201 | Purpose. | — |
| 51.1202 | Applicability. | — |
| 51.1203 | Air agency requirements. | — |
| 51.1204 | Enforceable emission limits providing for attainment. | — |
| 51.1205 | Ongoing data requirements. | — |
| 51.1300 | Definitions. | — |
| 51.1301 | Applicability of this part. | — |
| 51.1302 | Classification and nonattainment area planning provisions. | — |
| 51.1303 | Application of classification and attainment date provisions in CAA section 181 to areas subject to § 51.1302. | — |
| 51.1306 | Redesignation to nonattainment following initial designations. | — |
| 51.1307 | Determining eligibility for 1-year attainment date extensions for an 8-hour ozone NAAQS under CAA section 181(a)(5). | — |
| 51.1308 | Modeling and attainment demonstration requirements. | — |
| 51.1310 | Requirements for reasonable further progress (RFP). | — |
| 51.1312 | Requirements for reasonably available control technology (RACT) and reasonably available control measures (RACM). | — |
| 51.1313 | Section 182(f) NOX exemption provisions. | — |
| 51.1314 | New source review requirements. | — |
| 51.1315 | Emissions inventory requirements. | — |
| 51.1316 | Requirements for an Ozone Transport Region. | — |
| 51.1317 | Fee programs for Severe and Extreme nonattainment areas that fail to attain. | — |
| 51.1318 | Suspension of SIP planning requirements in nonattainment areas that have air quality data that meet an ozone NAAQS. | — |
| 51.1400 | Definitions. | — |
| 51.1401 | Applicability of part 51. | — |
| 51.1402 | SIP submission and control measure implementation deadlines for reclassified ozone nonattainment areas. | — |
| 51.1403 | Applicability of ozone SIP requirements for former classification after reclassification. | — |
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