{"abstract":"Based on its review of the air quality criteria for ozone (O<INF>3</INF>) and related photochemical oxidants and national ambient air quality standards (NAAQS) for O<INF>3</INF>, EPA is making revisions to the primary and secondary NAAQS for O<INF>3</INF> to provide requisite protection of public health and welfare, respectively. With regard to the primary standard for O<INF>3</INF>, EPA is revising the level of the 8-hour standard to 0.075 parts per million (ppm), expressed to three decimal places. With regard to the secondary standard for O<INF>3</INF>, EPA is revising the current 8- hour standard by making it identical to the revised primary standard. EPA is also making conforming changes to the Air Quality Index (AQI) for O<INF>3</INF>, setting an AQI value of 100 equal to 0.075 ppm, 8- hour average, and making proportional changes to the AQI values of 50, 150 and 200.","action":"Final rule.","agencies":[{"raw_name":"ENVIRONMENTAL PROTECTION AGENCY","name":"Environmental Protection Agency","id":145,"url":"https://www.federalregister.gov/agencies/environmental-protection-agency","json_url":"https://www.federalregister.gov/api/v1/agencies/145","parent_id":null,"slug":"environmental-protection-agency"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2008/03/27/E8-5645.html","cfr_references":[{"chapter":null,"citation_url":null,"part":50,"title":40},{"chapter":null,"citation_url":null,"part":58,"title":40}],"citation":"73 FR 16436","comment_url":null,"comments_close_on":null,"correction_of":null,"corrections":[],"dates":"This final rule is effective on May 27, 2008.","disposition_notes":null,"docket_ids":["EPA-HQ-OAR-2005-0172","FRL-8544-3"],"dockets":[],"document_number":"E8-5645","effective_on":"2008-05-27","end_page":16514,"executive_order_notes":null,"executive_order_number":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2008/03/27/E8-5645.xml","html_url":"https://www.federalregister.gov/documents/2008/03/27/E8-5645/national-ambient-air-quality-standards-for-ozone","images":{"ER27MR08.002":{"large":"https://img.federalregister.gov/ER27MR08.002/ER27MR08.002_large.png","medium":"https://img.federalregister.gov/ER27MR08.002/ER27MR08.002_medium.png","original_size":"https://img.federalregister.gov/ER27MR08.002/ER27MR08.002_original_size.png"},"ER27MR08.001":{"large":"https://img.federalregister.gov/ER27MR08.001/ER27MR08.001_large.png","medium":"https://img.federalregister.gov/ER27MR08.001/ER27MR08.001_medium.png","original_size":"https://img.federalregister.gov/ER27MR08.001/ER27MR08.001_original_size.png"},"ER27MR08.000":{"large":"https://img.federalregister.gov/ER27MR08.000/ER27MR08.000_large.png","medium":"https://img.federalregister.gov/ER27MR08.000/ER27MR08.000_medium.png","original_size":"https://img.federalregister.gov/ER27MR08.000/ER27MR08.000_original_size.png"},"ER27MR08.004":{"large":"https://img.federalregister.gov/ER27MR08.004/ER27MR08.004_large.png","medium":"https://img.federalregister.gov/ER27MR08.004/ER27MR08.004_medium.png","original_size":"https://img.federalregister.gov/ER27MR08.004/ER27MR08.004_original_size.png"},"ER27MR08.003":{"large":"https://img.federalregister.gov/ER27MR08.003/ER27MR08.003_large.png","medium":"https://img.federalregister.gov/ER27MR08.003/ER27MR08.003_medium.png","original_size":"https://img.federalregister.gov/ER27MR08.003/ER27MR08.003_original_size.png"}},"images_metadata":{"ER27MR08.002":{"large":{"identifier":"ER27MR08.002","content_type":"image/png","size":2645,"width":362,"sha":"40d65f67dc7de3334d48ade39c30538b","url":"https://img.federalregister.gov/ER27MR08.002/ER27MR08.002_large.png","height":70},"medium":{"identifier":"ER27MR08.002","content_type":"image/png","size":971,"width":171,"sha":"c8d789607ee8c44d22523e22b2b218d0","url":"https://img.federalregister.gov/ER27MR08.002/ER27MR08.002_medium.png","height":33},"original_size":{"identifier":"ER27MR08.002","content_type":"image/png","size":714,"width":155,"sha":"cc3604dd2b1db5d84c7c676fc36a616a","url":"https://img.federalregister.gov/ER27MR08.002/ER27MR08.002_original_size.png","height":30}},"ER27MR08.001":{"large":{"identifier":"ER27MR08.001","content_type":"image/png","size":3206,"width":525,"sha":"2a294b4e5e1e31df86d2104b7c694860","url":"https://img.federalregister.gov/ER27MR08.001/ER27MR08.001_large.png","height":70},"medium":{"identifier":"ER27MR08.001","content_type":"image/png","size":1221,"width":248,"sha":"b098987a4c6b194339698f9f3ae2bfad","url":"https://img.federalregister.gov/ER27MR08.001/ER27MR08.001_medium.png","height":33},"original_size":{"identifier":"ER27MR08.001","content_type":"image/png","size":836,"width":225,"sha":"afc07dfc4e6680d01004e3e1ade0a7a8","url":"https://img.federalregister.gov/ER27MR08.001/ER27MR08.001_original_size.png","height":30}},"ER27MR08.000":{"large":{"identifier":"ER27MR08.000","content_type":"image/png","size":4701,"width":771,"sha":"14cf6388d8576469362e9dbbf737c19e","url":"https://img.federalregister.gov/ER27MR08.000/ER27MR08.000_large.png","height":68},"medium":{"identifier":"ER27MR08.000","content_type":"image/png","size":1661,"width":363,"sha":"8716b7c2e53491262a6b4cf003658aac","url":"https://img.federalregister.gov/ER27MR08.000/ER27MR08.000_medium.png","height":32},"original_size":{"identifier":"ER27MR08.000","content_type":"image/png","size":1172,"width":329,"sha":"99c3eb4d5c8018c0c73bfc99ee4560c3","url":"https://img.federalregister.gov/ER27MR08.000/ER27MR08.000_original_size.png","height":29}},"ER27MR08.004":{"large":{"identifier":"ER27MR08.004","content_type":"image/png","size":3323,"width":436,"sha":"1e51d0cf5779014337277f08946b09a6","url":"https://img.federalregister.gov/ER27MR08.004/ER27MR08.004_large.png","height":70},"medium":{"identifier":"ER27MR08.004","content_type":"image/png","size":1146,"width":206,"sha":"7372087b02a83055a2600dc4bc4987ea","url":"https://img.federalregister.gov/ER27MR08.004/ER27MR08.004_medium.png","height":33},"original_size":{"identifier":"ER27MR08.004","content_type":"image/png","size":783,"width":187,"sha":"aba388e1fbc5bf95c19ab48f5a057003","url":"https://img.federalregister.gov/ER27MR08.004/ER27MR08.004_original_size.png","height":30}},"ER27MR08.003":{"large":{"identifier":"ER27MR08.003","content_type":"image/png","size":3227,"width":436,"sha":"def1a490f4fa2265682bfe54813c708d","url":"https://img.federalregister.gov/ER27MR08.003/ER27MR08.003_large.png","height":70},"medium":{"identifier":"ER27MR08.003","content_type":"image/png","size":1197,"width":206,"sha":"b56ad5b2553b7ed980f33845033db3a4","url":"https://img.federalregister.gov/ER27MR08.003/ER27M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22:15:04 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2008-03-27/pdf/E8-5645.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":null,"publication_date":"2008-03-27","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2008/03/27/E8-5645.txt","regulation_id_number_info":{"2060-AN24":{"issue":"200710","html_url":"https://www.federalregister.gov/regulations/2060-AN24/review-of-the-national-ambient-air-quality-standards-for-ozone","title":"Review of the National Ambient Air Quality Standards for Ozone","xml_url":"http://www.reginfo.gov/public/do/eAgendaViewRule?pubId=200710&RIN=2060-AN24&operation=OPERATION_EXPORT_XML","priority_category":"Economically Significant"}},"regulation_id_numbers":["2060-AN24"],"regulations_dot_gov_info":{"checked_regulationsdotgov_at":"2011-11-14T00:27:31Z"},"regulations_dot_gov_url":null,"significant":true,"signing_date":null,"start_page":16436,"subtype":null,"title":"National Ambient Air Quality Standards for Ozone","toc_doc":"National Ambient Air Quality Standards for Ozone","toc_subject":null,"topics":["Air pollution control","Carbon monoxide","Environmental protection","Lead","Nitrogen dioxide","Ozone","Particulate matter","Reporting and recordkeeping requirements","Sulfur oxides"],"type":"Rule","volume":73}