Science.gov

Sample records for 8-hour ozone naaqs

  1. 40 CFR 52.1989 - Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hour ozone NAAQS and 1997 PM2.5 NAAQS. 52.1989 Section 52.1989 Protection of Environment ENVIRONMENTAL... (CONTINUED) Oregon § 52.1989 Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS. (a... 8-hour ozone NAAQS and 1997 PM2.5 NAAQS. The SIP revision also meets the requirements of Clean...

  2. 40 CFR 52.1989 - Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hour ozone NAAQS and 1997 PM2.5 NAAQS. 52.1989 Section 52.1989 Protection of Environment ENVIRONMENTAL... (CONTINUED) Oregon § 52.1989 Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS. (a... 8-hour ozone NAAQS and 1997 PM2.5 NAAQS. The SIP revision also meets the requirements of Clean...

  3. 40 CFR 52.1989 - Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hour ozone NAAQS and 1997 PM2.5 NAAQS. 52.1989 Section 52.1989 Protection of Environment ENVIRONMENTAL... (CONTINUED) Oregon § 52.1989 Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS. (a... 8-hour ozone NAAQS and 1997 PM2.5 NAAQS. The SIP revision also meets the requirements of Clean...

  4. 40 CFR 52.1989 - Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS. 52.1989 Section 52.1989 Protection of Environment ENVIRONMENTAL... (CONTINUED) Oregon § 52.1989 Interstate Transport for the 1997 8-hour ozone NAAQS and 1997 PM2.5 NAAQS....

  5. 40 CFR 52.1393 - Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the 1997 8-hour ozone and PM2.5 NAAQS. 52.1393 Section 52.1393 Protection of Environment ENVIRONMENTAL... (CONTINUED) Montana § 52.1393 Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS. The... Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated in July 1997. The...

  6. 40 CFR 52.1393 - Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the 1997 8-hour ozone and PM2.5 NAAQS. 52.1393 Section 52.1393 Protection of Environment ENVIRONMENTAL... (CONTINUED) Montana § 52.1393 Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS. The... Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated in July 1997. The...

  7. 40 CFR 52.1393 - Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the 1997 8-hour ozone and PM2.5 NAAQS. 52.1393 Section 52.1393 Protection of Environment ENVIRONMENTAL... (CONTINUED) Montana § 52.1393 Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS. The... Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated in July 1997. The...

  8. 40 CFR 52.1393 - Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the 1997 8-hour ozone and PM2.5 NAAQS. 52.1393 Section 52.1393 Protection of Environment ENVIRONMENTAL... (CONTINUED) Montana § 52.1393 Interstate Transport Declaration for the 1997 8-hour ozone and PM2.5 NAAQS. The... Section 110(a)(2)(D)(i) for the 8-hour ozone and PM2.5 NAAQS promulgated in July 1997. The...

  9. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  10. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  11. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  12. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  13. 40 CFR 52.387 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hour ozone and PM2.5 NAAQS. 52.387 Section 52.387 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.387 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On March 13, 2007, the State...)(D)(i) interstate transport requirements of the Clean Air Act for the 1997 8-hour ozone and...

  14. 40 CFR 52.2499 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.2499 Section 52.2499 Protection of Environment ENVIRONMENTAL PROTECTION...) Washington § 52.2499 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On January 17, 2007,...

  15. 40 CFR 52.97 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.97 Section 52.97 Protection of Environment ENVIRONMENTAL PROTECTION....97 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On February 7, 2008, the...

  16. 40 CFR 52.97 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.97 Section 52.97 Protection of Environment ENVIRONMENTAL PROTECTION....97 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On February 7, 2008, the...

  17. 40 CFR 52.2499 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.2499 Section 52.2499 Protection of Environment ENVIRONMENTAL PROTECTION...) Washington § 52.2499 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On January 17, 2007,...

  18. 40 CFR 52.2499 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.2499 Section 52.2499 Protection of Environment ENVIRONMENTAL PROTECTION...) Washington § 52.2499 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On January 17, 2007,...

  19. 40 CFR 52.97 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.97 Section 52.97 Protection of Environment ENVIRONMENTAL PROTECTION....97 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On February 7, 2008, the...

  20. 40 CFR 52.97 - Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. 52.97 Section 52.97 Protection of Environment ENVIRONMENTAL PROTECTION....97 Interstate Transport for the 1997 8-hour ozone and PM2.5 NAAQS. On February 7, 2008, the...

  1. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  2. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  3. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  4. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 2 2012-07-01 2012-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  5. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false What are the requirements for an Ozone... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.916 What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? (a) In...

  6. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality... subsequently redesignated to nonattainment for the 8-hour ozone NAAQS, any absolute, fixed date applicable...

  7. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality... subsequently redesignated to nonattainment for the 8-hour ozone NAAQS, any absolute, fixed date applicable...

  8. 40 CFR 51.913 - How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.913... designated nonattainment for the 8-hour ozone NAAQS and for any area in a section 184 ozone transport...

  9. 40 CFR 51.913 - How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.913... designated nonattainment for the 8-hour ozone NAAQS and for any area in a section 184 ozone transport...

  10. 40 CFR 51.915 - What emissions inventory requirements apply under the 8-hour NAAQS?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... nonattainment area subject only to title I, part D, subpart 1 of the Act in accordance with § 51.902(b), the... emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part 51... apply under the 8-hour NAAQS? 51.915 Section 51.915 Protection of Environment ENVIRONMENTAL...

  11. 40 CFR 51.906 - Redesignation to nonattainment following initial designations for the 8-hour NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... following initial designations for the 8-hour NAAQS. 51.906 Section 51.906 Protection of Environment... Standard § 51.906 Redesignation to nonattainment following initial designations for the 8-hour NAAQS. For any area that is initially designated attainment or unclassifiable for the 8-hour NAAQS and that...

  12. 40 CFR 51.913 - How do the section 182(f) NOX exemption provisions apply for the 8-hour NAAQS?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... provisions apply for the 8-hour NAAQS? 51.913 Section 51.913 Protection of Environment ENVIRONMENTAL... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.913... petition the Administrator for an exemption from NOX obligations under section 182(f) for any...

  13. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  14. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  15. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  16. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  17. 40 CFR 51.908 - What modeling and attainment demonstration requirements apply for purposes of the 8-hour ozone...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... demonstration requirements apply for purposes of the 8-hour ozone NAAQS? 51.908 Section 51.908 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... purposes of the 8-hour ozone NAAQS? (a) What is the attainment demonstration requirement for an...

  18. 76 FR 54412 - Determination of Nonattainment and Reclassification of the Baltimore 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... Ozone Nonattainment Area; MD AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY: EPA is proposing to determine that the Baltimore moderate 8- hour ozone nonattainment area (the Baltimore Area) did not attain the 1997 8-hour ozone national ambient air quality standard (NAAQS) by...

  19. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  20. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  1. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  2. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  3. 40 CFR 51.918 - Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? 51.918... 8-hour Ozone National Ambient Air Quality Standard § 51.918 Can any SIP planning requirements be suspended in 8-hour ozone nonattainment areas that have air quality data that meets the NAAQS? Upon...

  4. 78 FR 32222 - Approval and Promulgation of Implementation Plans; Atlanta, Georgia 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-29

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Implementation Plans; Atlanta, Georgia 1997 8-Hour..., 2009, to address the reasonable further progress (RFP) plan requirements for the Atlanta, Georgia 1997 8-hour ozone national ambient air quality standards (NAAQS) nonattainment area. The Atlanta,...

  5. 78 FR 44439 - Approval and Promulgation of Implementation Plans: Atlanta, Georgia 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Implementation Plans: Atlanta, Georgia 1997 8-Hour... Atlanta, Georgia 1997 8-hour ozone national ambient air quality standards (NAAQS) nonattainment area. EPA... Planning Branch, U.S. Environmental Protection Agency Region 4, 61 Forsyth Street SW., Atlanta,...

  6. 76 FR 33647 - Approval and Promulgation of Determination of Attainment for the 1997 8-Hour Ozone Standard...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-09

    ... 51.918, a final determination that the area has met the 1997 8-hour ozone standard suspends the state... nonattainment area has attained the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51... (MO-IL) metropolitan nonattainment area has attained the 1997 8-hour National Ambient Air...

  7. 75 FR 51960 - Proposed Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: New...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-24

    ... AGENCY 40 CFR Part 51 RIN 2060-AP30 Proposed Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: New Source Review Anti-Backsliding Provisions for Former 1-Hour Ozone Standard AGENCY... designated nonattainment for the 1997 8-hour ozone national ambient air quality standard (NAAQS). The...

  8. Air Emissions Inventory Guidance for Implementation of Ozone and Particulate Matter NAAQS and Regional Haze Regulations

    EPA Pesticide Factsheets

    Guidance document on how to develop emission inventories to meet State Implementation Plan requirements for complying with the 8-hour ozone national ambient air quality standards (NAAQS), the revised particulate matter (PM) NAAQS, and the regional haze reg

  9. 40 CFR 51.905 - How do areas transition from the 1-hour NAAQS to the 1997 8-hour NAAQS and what are the anti...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... NAAQS to the 1997 8-hour NAAQS and what are the anti-backsliding provisions? 51.905 Section 51.905... National Ambient Air Quality Standard § 51.905 How do areas transition from the 1-hour NAAQS to the 1997 8... implement the applicable requirements as defined in § 51.900(f), except as provided in paragraph...

  10. 78 FR 32135 - Approval and Promulgation of Implementation Plans; Atlanta, Georgia 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-29

    ...EPA is taking direct final action to approve a state implementation plan (SIP) revision, submitted by the State of Georgia, through the Georgia Environmental Protection Division (GA EPD), on October 21, 2009, to address the reasonable further progress (RFP) plan requirements for the Atlanta, Georgia 1997 8-hour ozone national ambient air quality standards (NAAQS) nonattainment area. The......

  11. 40 CFR 51.915 - What emissions inventory requirements apply under the 8-hour NAAQS?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... AGENCY (CONTINUED) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.915 What... emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part...

  12. 40 CFR 51.915 - What emissions inventory requirements apply under the 8-hour NAAQS?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... AGENCY (CONTINUED) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.915 What... emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part...

  13. Ozone NAAQS Review: Policy Assessment

    EPA Science Inventory

    Ozone is one of the six major air pollutants for which EPA has issued air quality criteria and established national ambient air quality standards (NAAQS) based on those criteria. The Clean Air Act (CAA) requires EPA to periodically review and revise, as appropriate, existing air...

  14. 77 FR 35285 - Approval of Air Quality Implementation Plan; Arizona; Attainment Plan for 1997 8-Hour Ozone Standard

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    ... Ozone Standard AGENCY: U.S. Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: EPA is... demonstrate attainment of the 1997 8-hour ozone national ambient air quality standards (NAAQS) in the Phoenix... the SIP elements required for ozone nonattainment areas under title I, part D, subpart 1 of the...

  15. 75 FR 80420 - Reasonable Further Progress Requirements for the 1997 8-Hour Ozone National Ambient Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-22

    ... Ozone National Ambient Air Quality Standard AGENCY: Environmental Protection Agency (EPA). ACTION... 1997 8-hour ozone national ambient air quality standards (NAAQS). Specifically, EPA is proposing that... nitrogen oxides (NO X )] that contribute to ground-level ozone concentrations. B. What should I consider...

  16. 77 FR 21690 - Approval and Promulgation of Air Quality Implementation Plan for 1997 8-Hour Ozone Standard; Arizona

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-11

    ... Ozone Nonattainment Area A. Background on the 1997 8-Hour Ozone NAAQS Ground-level ozone pollution is... by many types of pollution sources including on- and off-road motor vehicles and engines, power plants and industrial facilities, and smaller area sources such as lawn and garden equipment and...

  17. 40 CFR 51.905 - How do areas transition from the 1-hour NAAQS to the 8-hour NAAQS and what are the anti...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National...) Submit an 8-hour ozone attainment demonstration no later than 1 year following designations...

  18. 40 CFR 51.905 - How do areas transition from the 1-hour NAAQS to the 8-hour NAAQS and what are the anti...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National...) Submit an 8-hour ozone attainment demonstration no later than 1 year following designations...

  19. 75 FR 68736 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard for the Delaware...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ... .067 42-045-0002 Delaware/Pennsylvania 2009 .065 42-091-0013 Montgomery/Pennsylvania......... 2009 .070... standard (NAAQS). This extension is based in part on air quality data recorded during the 2009 ozone season. Specifically, the Philadelphia Area's 4th highest daily 8-hour monitored ozone value during the 2009...

  20. 75 FR 79302 - Determination of Nonattainment and Reclassification of the Dallas/Fort Worth 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-20

    ...-Hour Ozone Nonattainment Area; Texas AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule... nonattainment area failed to attain the 1997 8-hour ozone national ambient air quality standard (NAAQS or... Federal Regulations (CFR) for moderate nonattainment areas. This final determination is based on...

  1. 76 FR 2859 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Adoption of 8-hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-18

    ...EPA proposes to approve the State Implementation Plan (SIP) revision submitted by the Commonwealth of Virginia for the purpose of adding the 2008 8-hour ozone National Ambient Air Quality Standard (NAAQS) of 0.075 parts per million (ppm), related reference conditions, and updating the list of appendices under ``Documents Incorporated by Reference.'' In the Final Rules section of this Federal......

  2. 75 FR 43069 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard in the Baltimore...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    .... 40 CFR 51.907 sets forth how sections 172(a)(2)(C) and 181(a)(5) apply to an area subject to the 1997 8-hour ozone NAAQS. Under 40 CFR 51.907, an area will meet the requirement of section 172(a)(2)(C... Baltimore Moderate Nonattainment Area AGENCY: Environmental Protection Agency (EPA). ACTION: Direct...

  3. Ozone NAAQS Review: Risk/Exposure Assessment

    EPA Science Inventory

    Ozone is one of the six major air pollutants for which EPA has issued air quality criteria and established national ambient air quality standards (NAAQS) based on those criteria. The Clear Air Act (CAA) requires EPA to periodically review and revise, as appropriate, existing air ...

  4. 75 FR 54778 - Approval and Promulgation of Air Quality Implementation Plans; Louisiana; Baton Rouge 8-Hour...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-09

    ... Rouge 8-Hour Ozone Nonattainment Area; Determination of Attainment of the 8-Hour Ozone Standard AGENCY... (BR) moderate 8- hour ozone nonattainment area has attained the 1997 8-hour ozone National Ambient Air... air monitoring data that show the area has monitored attainment of the 1997 8-hour ozone NAAQS for...

  5. Guidance on Developing Fee Programs Required by Clean Air Act Section 185 for the 1997 1-hour Ozone National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    This January 2010 memorandum provides additional guidance on fee collection programs for the 1997 1-hour ozone NAAQS, which are required as anti-backsliding measures during transition to the 1997 8-hour ozone standard.

  6. 78 FR 34965 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Ohio; 1997 8-Hour Ozone Maintenance Plan Revision; Motor Vehicle Emissions Budgets for the Ohio Portion of the Wheeling... Act, EPA is proposing to approve the request by Ohio to revise the 1997 8-hour ozone maintenance...

  7. 75 FR 9781 - Determination of Nonattainment and Reclassification of the Atlanta, Georgia, 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... Ozone Nonattainment Area; Correction AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule..., area from marginal to moderate for the 1997 8-hour ozone nonattainment area by operation of law. This....311. The reclassification of the Atlanta Area from marginal to moderate for the 1997 8-hour...

  8. 75 FR 42672 - Approval and Promulgation of Implementation Plans; New Jersey; 8-hour Ozone Control Measures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Implementation Plans; New Jersey; 8- hour Ozone... Implementation Plan (SIP) for ozone involving the control of volatile organic compounds (VOCs). The proposed SIP... ozone. DATES: Comments must be received on or before August 23, 2010. ADDRESSES: Submit your...

  9. 75 FR 80340 - Approval and Promulgation of Implementation Plans; New Jersey; 8-Hour Ozone Control Measures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-22

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Implementation Plans; New Jersey; 8- Hour Ozone... Plan (SIP) for ozone involving the control of volatile organic compounds (VOCs). The SIP revision... ozone. DATES: Effective Date: This rule is effective on January 21, 2011. ADDRESSES: EPA has...

  10. 40 CFR 51.907 - For an area that fails to attain the 8-hour NAAQS by its attainment date, how does EPA interpret...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.907 For an area...

  11. 40 CFR 51.907 - For an area that fails to attain the 8-hour NAAQS by its attainment date, how does EPA interpret...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) AIR PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.907 For an area...

  12. 40 CFR 51.905 - How do areas transition from the 1-hour NAAQS to the 1997 8-hour NAAQS and what are the anti...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... met its obligation to have a fully-approved attainment demonstration SIP for the 1-hour NAAQS, the... SIP at the time of the effective date of designation and in addition to national or regional measures... obligation for an approved 1-hour ROP SIP, it must develop and submit to EPA all outstanding 1-hour ROP...

  13. 2008 Ozone National Ambient Air Quality Standards (NAAQS) Infrastructure Actions

    EPA Pesticide Factsheets

    Read about the EPA's infrastructure actions for the 2008 Ozone NAAQS. These actions are regarding states' failure to submit SIPs addressing various parts of the standards. Here you can read the federal register notices, fact sheets, and the docket folder.

  14. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas?...

  15. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas?...

  16. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas?...

  17. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas?...

  18. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.914 What new source review requirements apply for 8-hour ozone nonattainment areas?...

  19. 40 CFR 51.907 - For an area that fails to attain the 8-hour NAAQS by its attainment date, how does EPA interpret...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.907 For an area that... 40 Protection of Environment 2 2014-07-01 2014-07-01 false For an area that fails to attain the 8... the CAA? 51.907 Section 51.907 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  20. EPA Approves Redesignation of Knoxville Area to Attainment for the 2008 8-Hour Ozone Standard

    EPA Pesticide Factsheets

    (07/13/15 - ATLANTA ) - Today, the U.S. Environmental Protection Agency announced that it is taking final action to approve the state of Tennessee's request to redesignate the Knoxville area to attainment for the 2008 8-hour ozone standard. This actio

  1. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  2. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  3. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  4. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  5. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  6. 75 FR 57220 - Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: New Source Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-20

    ... AGENCY 40 CFR Part 51 RIN 2060-AP30 Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: New Source Review Anti-Backsliding Provisions for Former 1-Hour Ozone Standard--Public Hearing... is announcing a public hearing to be held for the proposed ``Rule to Implement the 1997 8-Hour...

  7. 75 FR 55977 - Adequacy Status of the Knoxville, TN 1997 8-Hour Ozone Maintenance Plan Motor Vehicle Emission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-15

    ... Vehicle Emission Budgets for Transportation Conformity Purposes AGENCY: Environmental Protection Agency... the Knoxville, Tennessee 1997 8-Hour Ozone Maintenance Plan are adequate for transportation conformity... used for transportation conformity determinations until EPA has affirmatively found them adequate. As...

  8. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  9. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  10. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  11. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  12. 40 CFR 51.917 - What is the effective date of designation for the Las Vegas, NV, 8-hour ozone nonattainment area?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... designation for the Las Vegas, NV, 8-hour ozone nonattainment area? 51.917 Section 51.917 Protection of..., AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient... ozone nonattainment area? The Las Vegas, NV, 8-hour ozone nonattainment area (designated on September...

  13. 76 FR 2829 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Adoption of 8-hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-18

    ... NAAQS for ozone on March 27, 2008 (73 FR 16436). II. Summary of SIP Revision On September 27, 2010, the... Budget under Executive Order 12866 (58 FR 51735, October 4, 1993); Does not impose an information...); Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August...

  14. 2015 Revision to 2008 Ozone National Ambient Air Quality Standards (NAAQS) Supporting Documents

    EPA Pesticide Factsheets

    Find tools for background ozone, maps of nonattainment areas, an overview of the proposal, and information on designations, monitoring and permitting requirements and a presentation on the 2015 ozone NAAQS revision.

  15. 2014 Proposed Revision to 2008 Ozone National Ambient Air Quality Standards (NAAQS) Supporting Documents

    EPA Pesticide Factsheets

    Find information on the 2014 proposed ozone NAAQS revision, and find tools for background ozone, maps of nonattainment areas, an overview of the proposal, and information on designations, monitoring and permitting requirements

  16. 76 FR 13289 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard in the Baltimore...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-11

    ... Appendix A can be found in the ``Quality Assurance Handbook for Air Pollution Measurement Systems,'' volume...).) List of Subjects in 40 CFR Part 81 Environmental protection, Air pollution control, National parks... Baltimore nonattainment area, which is classified as moderate for the 1997 8-hour ozone National Ambient...

  17. Air Quality Modeling Technical Support Document for the 2015 Ozone NAAQS Preliminary Interstate Transport Assessment

    EPA Pesticide Factsheets

    In this technical support document (TSD) EPA describes the air quality modeling performed to support the 2015 ozone National Ambient Air Quality Standards (NAAQS) preliminary interstate transport assessment Notice of Data Availability (NODA).

  18. 75 FR 26225 - Adequacy Status of the Chicago, Illinois Area Submitted 8-Hour Ozone Redesignation and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-11

    ... Plans for Transportation Conformity Purposes AGENCY: Environmental Protection Agency (EPA). ACTION... conformity determinations. Illinois submitted a redesignation request and maintenance plan for the Illinois... must use the MVEBs from the submitted ozone maintenance plan for future transportation...

  19. 75 FR 232 - Finding of Failure To Submit Certain State Implementation Plans Required for the 1-Hour Ozone NAAQS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-05

    ... Ozone NAAQS AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: The EPA is... Implementation Plans (SIPs) for three ozone nonattainment areas to satisfy certain requirements of the Clean Air Act (CAA) for the 1-hour ozone National Ambient Air Quality Standards (NAAQS). To accompany...

  20. 78 FR 65877 - Approval and Promulgation of Implementation Plans; Atlanta, Georgia 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... Area. Signal preemption for MARTA Atlanta 6/17/96 4/26/99. routes 15 and 23. Improve and expand service... for Control Atlanta 1997 8- 10/21/2009........ 09/28/2013. of VOC Emissions from Reactor Hour Ozone Processes and Distillation Nonattainment Operations in Synthetic Organic Area. Chemical...

  1. Trends analyses of 30 years of ambient 8 hour ozone and precursor monitoring data in the South Central U.S.: progress and challenges.

    PubMed

    Sather, Mark E; Cavender, Kevin

    2016-07-13

    In the last 30 years ambient ozone concentrations have notably decreased in the South Central U.S. Yet, current ambient ozone concentrations measured over the past three years 2013-2015 in this area of the U.S. are not meeting the U.S. 2015 8 hour ozone standard of 70 parts per billion (ppb). This paper provides an update on long-term trends analyses of ambient 8 hour ozone and ozone precursor monitoring data collected over the past 30 years (1986-2015) in four South Central U.S. cities, following up on two previously published reviews of 20 and 25 year trends for these cities. All four cities have benefitted from national ozone precursor controls put in place during the 1990s and 2000s involving cleaner vehicles (vehicle fleet turnover/replacement over time), cleaner fuels, cleaner gasoline and diesel engines, and improved inspection/maintenance programs for existing vehicles. Additional ozone precursor emission controls specific to each city are detailed in this paper. The controls have resulted in impressive ambient ozone and ambient ozone precursor concentration reductions in the four South Central U.S. cities over the past 30 years, including 31-70% ambient nitrogen oxides (NOx) concentration declines from historical peaks to the present, 43-72% volatile organic compound (VOC) concentration declines from historical peaks to the present, a related 45-76% VOC reactivity decline for a subset of VOC species from historical peaks to the present, and an 18-38 ppb reduction in city 8 hour ozone design value concentrations. A new challenge for each of the four South Central U.S. cities will be meeting the U.S. 2015 8 hour ozone standard of 70 ppb.

  2. Air Quality Modeling Technical Support Document for the 2008 Ozone NAAQS Cross-State Air Pollution Rule Proposal

    EPA Pesticide Factsheets

    In this technical support document (TSD) we describe the air quality modeling performed to support the proposed Cross-State Air Pollution Rule for the 2008 ozone National Ambient Air Quality Standards (NAAQS)

  3. 75 FR 8331 - Adequacy Status of the Cincinnati, Ohio/Indiana Submitted 8-Hour Ozone Redesignation and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ... Maintenance Plans for Transportation Conformity Purposes AGENCY: Environmental Protection Agency (EPA). ACTION... ozone nonattainment area are adequate for use in transportation conformity determinations. Ohio... ozone maintenance plan for future transportation conformity determinations. DATES: This finding...

  4. 75 FR 68733 - Approval and Promulgation of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    .../Pennsylvania 2009 .065 42-091-0013 Montgomery/Pennsylvania......... 2009 .070 42-101-0004 Philadelphia..., quality-assured air quality data recorded during the 2009 ozone season. In accordance with requirements... the 2009 ozone season at each monitor in the area is less than 0.084 parts per million (ppm). If...

  5. 75 FR 9893 - Adequacy Determination for the Denver Metro Area and North Front Range 8-Hour Ozone Attainment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... Plan's Motor Vehicle Emissions Budgets for Transportation Conformity Purposes; State of Colorado AGENCY... Attainment Plan (hereafter ``Denver/NFR Ozone Attainment Plan'') are adequate for transportation conformity... budgets for future transportation conformity determinations once this finding becomes effective....

  6. 40 CFR 52.1342 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.1342...: Ozone. (a) Determination of attainment. EPA has determined, as of June 9, 2011, that the St. Louis (MO-IL) metropolitan 1997 8-hour ozone nonattainment area has attained the 1997 8-hour ozone NAAQS....

  7. 40 CFR 52.1342 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Ozone. 52.1342...: Ozone. (a) Determination of attainment. EPA has determined, as of June 9, 2011, that the St. Louis (MO-IL) metropolitan 1997 8-hour ozone nonattainment area has attained the 1997 8-hour ozone NAAQS....

  8. 40 CFR 52.1342 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.1342...: Ozone. (a) Determination of attainment. EPA has determined, as of June 9, 2011, that the St. Louis (MO-IL) metropolitan 1997 8-hour ozone nonattainment area has attained the 1997 8-hour ozone NAAQS....

  9. 40 CFR 52.1342 - Control strategy: Ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Control strategy: Ozone. 52.1342...: Ozone. Determination of Attainment. EPA has determined, as of June 9, 2011, that the St. Louis (MO-IL) metropolitan 1997 8-hour ozone nonattainment area has attained the 1997 8-hour ozone NAAQS. This...

  10. Eastern Texas Air Quality Forecasting System to Support TexAQS-II and 8-hour Ozone Modeling

    NASA Astrophysics Data System (ADS)

    Byun, D. W.

    2005-12-01

    The main objective of the Second Texas Air Quality Study (TexAQS-II) for 2005 and 2006 is to understand emissions and processes associated with the formation and transport of ozone and regional haze in Texas. The target research area is the more populated eastern half of the state, roughly from Interstate 35 eastward. Accurate meteorological and photochemical modeling efforts are essential to support this study and further enhance modeling efforts for establishing the State Implementation Plan (SIP) by Texas Commission on Environmental Quality (TCEQ). An air quality forecasting (AQF) system for Eastern Texas has been developed to provide these data and to further facilitate retrospective simulations to allow for model improvement and increased understanding of ozone episodes and emissions. We perform two-day air quality forecasting simulations with the 12-km Eastern Texas regional domain, and the 4-km Houston-Galveston area (HGA) domain utilizing a 48-CPU Beowulf Linux computer system. The dynamic boundary conditions are provided by the 36-km resolution conterminous US (CONUS) domain CMAQ simulations. Initial meteorological conditions are provided by the daily ETA forecast results. The results of individual runs are stored and made available to researchers and state and local officials via internet to study the patterns of air quality and its relationship to weather conditions and emissions. The data during the pre- and post-processing stages are in tens of gigabytes and must be managed efficiently during both the actual real-time and the subsequent computation periods. The nature of these forecasts and the time at which the initial data is available necessitates that models be executed within tight deadlines. A set of complex operational scripts is used to allow automatic operation of the data download, sequencing processors, performing graphical analysis, building database archives, and presenting on the web.

  11. Memoranda Associated with the Second External Review Draft of Health Risk and Exposure Assessments from the Current Review of Ozone NAAQS

    EPA Pesticide Factsheets

    EPA's Health and Environmental Impacts Division had to make corrections to some of the risk results included in earlier drafts of the Health Risk and Exposure Assessment from the current review of ozone national ambient air quality standards (NAAQS).

  12. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  13. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  14. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  15. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  16. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the data... secondary ambient air quality standards for ozone specified in § 50.10 are met at an ambient ozone...

  17. 2008 Ozone National Ambient Air Quality Standards (NAAQS) Findings of Failure to Submit

    EPA Pesticide Factsheets

    This final action finds that 15 states and the District of Columbia have failed to submit specific state implementation plan (SIP) elements to satisfy certain nonattainment area, and/or Ozone Transport Region (OTR), planning requirements for the 2008 ozone

  18. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.582 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Georgia § 52.582 Control strategy: Ozone. (a) Approval... area has attaining data for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40...

  19. 40 CFR 52.1779 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.1779... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the bi... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends...

  20. 40 CFR 52.523 - Control strategy: Ozone

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Ozone 52.523 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Florida § 52.523 Control strategy: Ozone (a) Disapproval. EPA is disapproving portions of Florida's infrastructure SIP for the 1997 8-hour ozone NAAQS...

  1. 40 CFR 52.2125 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy: Ozone. 52.2125... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the bi... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends...

  2. 40 CFR 52.1779 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.1779... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the bi... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends...

  3. 40 CFR 52.1779 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Control strategy: Ozone. 52.1779... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the bi... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends...

  4. 40 CFR 52.2125 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.2125... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the bi... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends...

  5. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Ozone. 52.582 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Georgia § 52.582 Control strategy: Ozone. (a) Approval... area has attaining data for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40...

  6. 40 CFR 52.582 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.582 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Georgia § 52.582 Control strategy: Ozone. (a) Approval... area has attaining data for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40...

  7. 40 CFR 52.523 - Control strategy: Ozone

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Ozone 52.523 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Florida § 52.523 Control strategy: Ozone (a) Disapproval. EPA is disapproving portions of Florida's infrastructure SIP for the 1997 8-hour ozone NAAQS...

  8. 40 CFR 52.2125 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.2125... strategy: Ozone. (a) Determination of attaining data. EPA has determined, as of November 15, 2011, the bi... for the 1997 8-hour ozone NAAQS. This determination, in accordance with 40 CFR 51.918, suspends...

  9. A Procedure for Inter-Comparing the Skill of Regional-Scale Air Quality Model Simulations of Daily Maximum 8-Hour Ozone Concentrations

    EPA Science Inventory

    An operational model evaluation procedure is described to quantitatively assess the relative skill among several regionalscale air quality models simulating various percentiles of the cumulative frequency distribution of observed daily maximum 8-h ozone concentrations. Bootstrap ...

  10. Fact Sheet - Managing Ozone Air Quality: Findings on Failure to Submit Elements of 1997 Ozone NAAQS State Implementation Plan

    EPA Pesticide Factsheets

    This fact sheet provides a basic overview of the May 17, 2008 notice that 11 states missed their deadlines to submit their state implementation plans (SIPs). The deadlines are for submitting complete plans showing how they will meet the 1997 ozone standard

  11. 77 FR 8197 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: Nonattainment Area...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... 1997 Ozone Standards for Transportation Conformity Purposes AGENCY: Environmental Protection Agency... designations for the 2008 ozone NAAQS for transportation conformity purposes only. DATES: Comments must be... NAAQS D. Transportation Conformity and the 1997 Ozone NAAQS III. What are the proposed...

  12. 78 FR 34177 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-06

    ... the 2008 National Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements... Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements AGENCY: Environmental... 2008 ozone national ambient air quality standards (NAAQS) (the ``2008 ozone NAAQS'') that...

  13. NODA for EPA's Updated Ozone Transport Modeling

    EPA Pesticide Factsheets

    Find EPA's NODA for the Updated Ozone Transport Modeling Data for the 2008 Ozone National Ambient Air Quality Standard (NAAQS) along with the ExitExtension of Public Comment Period on CSAPR for the 2008 NAAQS.

  14. Updates to Information Presented in the Scope and Methods Plans for the Ozone NAAQS Health and Welfare Risk and Exposure Assessments, May 2012 Memo

    EPA Pesticide Factsheets

    This memorandum provides an overview of changes to the scope and methods plan, and reasons for them, to inform the CASAC Ozone Panel and the public as they prepare to review the first drafts of the Risk and Exposure Assessments.

  15. A survey of ozone concentrations in rural western Utah: unexpected results and spatial heterogeneity from 2010-2013

    NASA Astrophysics Data System (ADS)

    Arens, S. J.; Harper, K.

    2013-12-01

    Ozone concentrations and meteorological variables were monitored at eleven sites in rural western Utah during late spring through summer of 2010-2013 to determine regional background concentrations of ozone and to determine attainment or nonattainment of the ozone National Ambient Air Quality Standard (NAAQS). Ozone concentrations have been monitored along the Wasatch Front of Utah (Logan, Ogden, Salt Lake City and Provo) for 30 years by the Utah Division of Air Quality (DAQ), but no ozone data from outside the cities of Wasatch Front existed prior to 2010. All rural sites, except Badger Springs, west of St. George, UT, were in attainment of the ozone NAAQS, which is 75 ppb averaged over 8 hours. However, ozone concentrations were higher than expected at seven of the eleven sites. All eleven sites were located in either small rural towns or uninhabited areas of western Utah, which were distant from anthropogenic emissions of ozone precursors. In 2010, ozone concentrations were relatively low along the Wasatch Front of Utah. Ozone concentrations exceeded 65 ppb for one day at three of four rural sites. Ozone concentrations at two of the four sites were generally in the range of expected rural ozone concentrations of 50-60 ppb. Ozone concentrations during 2011-2012 were higher throughout Utah compared to 2010. In 2011, 8-hour ozone concentrations exceeded 70 ppb for at least one day at four of five sites. The maximum 8-hour ozone concentration was 78 ppb, observed at Lytle Ranch, west of St. George, UT. Ozone concentrations at only one rural Utah site were in the expected range of 50-60 ppb. Ozone concentrations during 2012 were the highest observed during the four years of the study with 8-hour ozone concentrations exceeding 75 ppb at three of five rural sites and exceeding 70 ppb for at least four days at four of five sites. Although data collected was not considered regulatory by the EPA, the ozone NAAQS was exceeded at Badger Springs in southwestern Utah. Ozone

  16. Primary Sulfur Dioxide NAAQS Implementation Schedule

    EPA Pesticide Factsheets

    The effective date for the primary sulfur dioxide (SO2) National Ambient Air Quality Standard (NAAQS) established in 2012, is followed by designations of nonattainment areas and subsequently required state implementation plans (SIPs).

  17. Overview of ozone human exposure and health risk analyses used in the U.S. EPA's review of the ozone air quality standard.

    SciTech Connect

    Whitfield, R. G.

    1999-03-04

    This paper presents an overview of the ozone human exposure and health risk analyses developed under sponsorship of the U.S. Environmental Protection Agency (EPA). These analyses are being used in the current review of the national ambient air quality standards (NAAQS) for ozone. The analyses consist of three principal steps: (1) estimating short-term ozone exposure for particular populations (exposure model); (2) estimating population response to exposures or concentrations (exposure-response or concentration-response models); and (3) integrating concentrations or exposure with concentration-response or exposure-response models to produce overall risk estimates (risk model). The exposure model, called the probabilistic NAAQS exposure model for ozone (pNEM/03), incorporates the following factors: hourly ambient ozone concentrations; spatial distribution of concentrations; ventilation state of individuals at time of exposure; and movement of people through various microenvironments (e.g., outdoors, indoors, inside a vehicle) of varying air quality. Exposure estimates are represented by probability distributions. Exposure-response relationships have been developed for several respiratory symptom and lung function health effects, based on the results of controlled human exposure studies. These relationships also are probabilistic and reflect uncertainties associated with sample size and variability of response among subjects. The analyses also provide estimates of excess hospital admissions in the New York City area based on results from an epidemiology study. Overall risk results for selected health endpoints and recently analyzed air quality scenarios associated with alternative 8-hour NAAQS and the current 1-hour standard for outdoor children are used to illustrate application of the methodology.

  18. PARTICULATE MATTER NAAQS RISK AND EXPOSURE ...

    EPA Pesticide Factsheets

    The PM REA assesses human exposure and health risks for particulate matter. To provide a quantitative assessment of PM exposures and health risks as one of the key information inputs to the Administrator in order to make an informed decision regarding the PM NAAQS. A tiered risk/exposure assessment will be conducted as part of the PM NAAQS review and will be peer reviewed by the Clean Air Scientific Advisory Committee (CASAC) of EPA’s Science Advisory Board.

  19. 76 FR 72919 - Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-28

    ... AGENCY Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants AGENCY..., ``Second External Review Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants... review of the national ambient air quality standards (NAAQS) for ozone. DATES: The public comment...

  20. 76 FR 17121 - Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-28

    ... AGENCY Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants AGENCY..., ``First External Review Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants... review of the national ambient air quality standards (NAAQS) for ozone. DATES: The public comment...

  1. 78 FR 47572 - Disapproval of State Implementation Plan; Infrastructure Requirements for the 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-06

    ... restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet...: Definitions For the purpose of this document, we are giving meaning to certain words or initials as...

  2. 75 FR 17915 - Agency Information Collection Activities; Proposed Collection; Comment Request; 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-08

    ... National Ambient Air Quality Standard, EPA ICR No. 2236.03, OMB Control No. 2060-0594 AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: In compliance with the Paperwork Reduction Act (PRA) (44 U.S.C. 3501 et seq.), this document announces that EPA is planning to submit a request to renew...

  3. 78 FR 34903 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... Emissions Simulator (MOVES) emissions model. Ohio submitted the SIP revision request to EPA on December 7... modeling and participated in the consultation process. The Federal Highway Administration and the...

  4. 78 FR 45188 - Agency Information Collection Activities; Proposed Collection; Comment Request; 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-26

    ..., mechanical or other technological collection techniques or other forms of information technology, e.g., by... Protection Agency, T.W. Alexander Drive, Research Triangle Park, NC 27711; telephone number: (919)...

  5. 78 FR 32613 - Disapproval of State Implementation Plan; Infrastructure Requirements for the 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-31

    ... agency certifies that the rule will not have a significant economic impact on a substantial number of... jurisdictions. For purposes of assessing the impacts of today's proposed rule on small entities, small entity is... its field. After considering the economic impacts of today's proposed rule on small entities,...

  6. 77 FR 30160 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: Nonattainment Area...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... 1997 Ozone Standards for Transportation Conformity Purposes AGENCY: Environmental Protection Agency... provides for the revocation of the 1997 ozone NAAQS for transportation conformity purposes to occur 1 year... Received C. Final Action VI. When is the EPA revoking the 1997 ozone NAAQS for transportation...

  7. Lead (Pb) NAAQS Review: Policy Assessment

    EPA Science Inventory

    The Policy Assessment (PA) is a component of the NAAQS review that bridges the gap between the scientific assessment contained in the Integrated Science Assessment and the judgments required of the EPA Administrator in determining whether it is appropriate to retain or revise the...

  8. NOx SOx Secondary NAAQS: Integrated Review Plan ...

    EPA Pesticide Factsheets

    The NOx SOx Secondary NAAQS Integrated Review Plan is the first document generated as part of the National Ambient Air Quality Standards (NAAQS) review process. The Plan presents background information, the schedule for the review, the process to be used in conducting the review, and the key policy-relevant science issues that will guide the review. The integrated review plan also discusses the frameworks for the various assessment documents to be prepared by the EPA as part of the review, including an Integrated Science Assessment (ISA), and as warranted, a Risk/Exposure Assessment (REA), and a Policy Assessment (PA). The primary purpose of the NOx SOx Secondary NAAQS Integrated Review Plan is to highlight the key policy-relevant issues to be considered in the Review of the Oxides of Nitrogen and Oxides of Sulfur Secondary NAAQS. A draft of the integrated review plan will be the subject of an advisory review with the Clean Air Scientific Advisory Committee (CASAC) and made available to the public for review and comment.

  9. Ozone

    MedlinePlus

    ... reactive form of oxygen. In the upper atmosphere, ozone forms a protective layer that shields us from the sun’s ultraviolet rays. At ground level, ozone is a harmful air pollutant and a primary ...

  10. Ozone

    MedlinePlus

    Ozone is a gas. It can be good or bad, depending on where it is. "Good" ozone occurs naturally about 10 to 30 miles above ... the sun's ultraviolet rays. Part of the good ozone layer is gone. Man-made chemicals have destroyed ...

  11. 76 FR 40624 - Approval and Promulgation of Implementation Plans; State of Kansas

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-11

    ... Air Quality Standards (NAAQS) for ozone. The rationale for this action is explained in this notice and... sections 110(a)(1) and (2) necessary to implement, maintain, and enforce the 1997 8-hour ozone NAAQS. II... enforcement of the 1997 8-hour ozone NAAQS. The rationale supporting EPA's proposed action is explained in...

  12. Identifying ozone production from oil and gas versus urban emissions sources in the Denver Metro Area and North Front Range of Colorado

    NASA Astrophysics Data System (ADS)

    Pollack, I. B.; Zaragoza, J.; Abeleira, A.; Flocke, F. M.; Farmer, D.; Fischer, E. V.

    2015-12-01

    During summertime, ozone concentrations in the Denver Metro Area and North Front Range of Colorado often exceed the 8-hour average EPA National Ambient Air Quality Standard (NAAQS) of 75 ppbv. Ambient measurements of ozone, ozone precursors - volatile organic compounds (VOC) and nitrogen oxides (NOx=NO+NO2) - and other secondary pollutants such as peroxyacetyl nitrate (PAN) were collected during spring (15 Mar-18 May) and summer (6 Jul-9 Sept) 2015 at the Boulder Atmospheric Observatory (BAO) in Erie, Colorado. These measurements were made in conjunction with airborne measurements from the Shale Oil and Gas Nexus (SONGNEX) field campaign in spring 2015, which focused on studying the air quality impacts of emissions from oil and gas production in the western U.S. Using the in-situ ground-based measurements collected at the BAO field site, we attempt to identify and compare regional ozone production originating from oil and gas emissions (e.g., the Denver-Julesburg oil basin northeast of BAO) with that from urban and mobile sources (e.g., the Denver/Boulder metropolitan area south and west of BAO). We use ozone production efficiency (i.e., the number of molecules of ozone produced per molecule of NOx oxidized) and emissions ratios of selected VOCs as a metric for comparing ozone production associated with these different sources of emissions as well as seasonal differences between observations collected in spring versus summer.

  13. 40 CFR 52.282 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy and regulations: Ozone... and regulations: Ozone. (a) Attainment determination. EPA has determined that the Ventura County severe 1-hour ozone nonattainment area attained the 1-hour ozone NAAQS by the applicable attainment...

  14. 40 CFR 52.282 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy and regulations: Ozone... and regulations: Ozone. (a) Attainment determination. EPA has determined that the Ventura County severe 1-hour ozone nonattainment area attained the 1-hour ozone NAAQS by the applicable attainment...

  15. 40 CFR 52.282 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy and regulations: Ozone... and regulations: Ozone. (a) Attainment determination. EPA has determined that the Ventura County severe 1-hour ozone nonattainment area attained the 1-hour ozone NAAQS by the applicable attainment...

  16. 40 CFR 52.282 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy and regulations: Ozone... and regulations: Ozone. (a) Attainment determination. EPA has determined that the Ventura County severe 1-hour ozone nonattainment area attained the 1-hour ozone NAAQS by the applicable attainment...

  17. 40 CFR 52.282 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy and regulations: Ozone... and regulations: Ozone. (a) Attainment determination. EPA has determined that the Ventura County severe 1-hour ozone nonattainment area attained the 1-hour ozone NAAQS by the applicable attainment...

  18. Air Quality Criteria for Ozone and Related Photochemical ...

    EPA Pesticide Factsheets

    In February 2006, EPA released the final document, Air Quality Criteria for Ozone and Other Photochemical Oxidants. Tropospheric or surface-level ozone (O3) is one of six major air pollutants regulated by National Ambient Air Quality Standards (NAAQS) under the U.S. Clean Air Act. As mandated by the Clean Air Act, the U.S. Environmental Protection Agency (EPA) must periodically review the scientific bases (or criteria) for the various NAAQS by assessing newly available scientific information on a given criteria air pollutant. This document, Air Quality Criteria for Ozone and Other Photochemical Oxidants, is an updated revision of the 1996 Ozone Air Quality Criteria Document (O3 AQCD) that provided scientific bases for the current O3 NAAQS set in 1997. The Clean Air Act mandates periodic review of the National Ambient Air Quality Standards (NAAQS) for six common air pollutants, also referred to as criteria pollutants, including ozone.

  19. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone...-hour NAAQS means the 1-hour ozone national ambient air quality standards codified at 40 CFR 50.9. (b) 8-hour NAAQS means the 8-hour ozone national ambient air quality standards codified at 40 CFR 50.10....

  20. 40 CFR 51.900 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone...-hour NAAQS means the 1-hour ozone national ambient air quality standards codified at 40 CFR 50.9. (b) 8-hour NAAQS means the 8-hour ozone national ambient air quality standards codified at 40 CFR 50.10....

  1. 78 FR 44890 - Approval and Promulgation of Implementation Plans; North Carolina; Control Techniques Guidelines...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-25

    ... Carolina 1997 8-hour ozone nonattainment area (hereafter referred to as the ``bi-state Charlotte Area... the bi-state Charlotte Area as a moderate nonattainment area with respect to the 1997 8-hour ozone NAAQS.\\1\\ See 69 FR 23858. The bi-state Charlotte Area for the 1997 8- hour ozone NAAQS includes...

  2. 75 FR 31306 - Approval and Promulgation of State Implementation Plans; State of Colorado; Interstate Transport...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-03

    ...; Interstate Transport of Pollution Revisions for the 1997 8- hour Ozone NAAQS: ``Significant Contribution to... of Clean Air Act section 110(a)(2)(D)(i)(I) for the 1997 8-hour ozone National Ambient Air Quality... do not ``contribute significantly'' to nonattainment of the 1997 8-hour ozone NAAQS in any...

  3. NOx SOx Secondary NAAQS: Integrated Review Plan - CASAC Advisory

    EPA Science Inventory

    The NOx SOx Secondary NAAQS Integrated Review Plan is the first document generated as part of the National Ambient Air Quality Standards (NAAQS) review process. The Plan presents background information, the schedule for the review, the process to be used in conducting the review,...

  4. 40 CFR 52.1174 - Control strategy: Ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... Appropriateness of a contingency measure will be determined by an urban airshed modeling analysis. The Governor or... NAAQS, determined not to be attributable to transport from upwind areas, is monitored, Michigan will... the area records a violation of the 1-hour ozone NAAQS, determined not to be attributable to...

  5. 77 FR 65490 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Fredericksburg 8-Hour...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-29

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Virginia... Virginia's State Implementation Plan (SIP) revision submitted by the Virginia Department of Environmental... model (MOVES2010a). The revised MVEBs continue to demonstrate maintenance of the 1997 8-hour...

  6. Ozone: Stage Two Vapor Recovery Rule and Guidance

    EPA Pesticide Factsheets

    This page includes the guidance document, fact sheet, memorandum, and final rule on removing Stage II Gasoline Vapor Control Programs from State Implementation Plans (SIP) for the Ozone National Ambient Air Quality Standards (NAAQS)

  7. Setting and Reviewing Standards to Control Ozone Pollution

    EPA Pesticide Factsheets

    Ozone standards are part of the National Ambient Air Quality Standards (NAAQS), which limit air pollution to protect health and the environment. Standards are periodically reviewed and updated, and air quality across the U.S. is measured against them.

  8. Ozone (O3) Standards - Policy Assessments from Current Review

    EPA Pesticide Factsheets

    The policy assessment (PA) provides a transparent staff analysis of the scientific basis for alternative policy options for consideration by senior EPA management prior to rulemaking. These are the policy assessments used to develop the ozone NAAQS.

  9. 77 FR 29904 - Approval and Promulgation of Implementation Plans; Oregon: Infrastructure Requirements for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... ozone on July 18, 1997. EPA finds that the current Oregon SIP meets the following 110(a)(2) infrastructure elements for the 1997 8-hour ozone NAAQS: (A), (B), (C), (D)(ii), (E), (F), (G), (H), (J), (K), (L.... Background On July 18, 1997, EPA promulgated a new NAAQS for ozone. EPA revised the ozone NAAQS to provide...

  10. 77 FR 64425 - Approval and Promulgation of Implementation Plans; Alaska: Infrastructure Requirements for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-22

    ... for ozone on July 18, 1997. EPA finds that the Alaska SIP meets the following 110(a)(2) infrastructure elements for the 1997 8- hour ozone NAAQS: (A), (B), (C), (D)(ii), (E), (F), (G), (H), (J), (K), (L), and... 18, 1997, EPA promulgated a new NAAQS for ozone. EPA revised the ozone NAAQS to provide an...

  11. Analyses of 1999 PM Data for the PM NAAQS Review

    EPA Pesticide Factsheets

    These files document all analyses conducted in association with the EPA memorandum from Terence Fitz-Simons, Scott Mathias, and Mike Rizzo titled Analyses of 1999 PM Data for the PM NAAQS Review, November 17, 2000.

  12. 40 CFR 52.350 - Control strategy: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Control strategy: Ozone. 52.350 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.350 Control strategy: Ozone. (a) Revisions to the Colorado State Implementation Plan, 1-hour ozone NAAQS Redesignation Request and...

  13. 40 CFR 52.350 - Control strategy: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Control strategy: Ozone. 52.350 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.350 Control strategy: Ozone. (a) Revisions to the Colorado State Implementation Plan, 1-hour ozone NAAQS Redesignation Request and...

  14. 40 CFR 52.2275 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control strategy and regulations: Ozone... strategy and regulations: Ozone. (a) Section 510.3 of revised Regulation V, which was submitted by the... Areas Did Not Attain the 1-Hour Ozone NAAQS. EPA has determined that the...

  15. 40 CFR 52.350 - Control strategy: Ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Control strategy: Ozone. 52.350 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.350 Control strategy: Ozone. (a) Revisions to the Colorado State Implementation Plan, 1-hour ozone NAAQS Redesignation Request and...

  16. 40 CFR 52.350 - Control strategy: Ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Control strategy: Ozone. 52.350 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.350 Control strategy: Ozone. (a) Revisions to the Colorado State Implementation Plan, 1-hour ozone NAAQS Redesignation Request and...

  17. 40 CFR 52.2275 - Control strategy and regulations: Ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control strategy and regulations: Ozone... strategy and regulations: Ozone. (a) Section 510.3 of revised Regulation V, which was submitted by the... Areas Did Not Attain the 1-Hour Ozone NAAQS. EPA has determined that the...

  18. 40 CFR 52.350 - Control strategy: Ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Ozone. 52.350 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.350 Control strategy: Ozone. (a) Revisions to the Colorado State Implementation Plan, 1-hour ozone NAAQS Redesignation Request and...

  19. Ozone

    SciTech Connect

    Not Available

    1988-06-01

    The author discusses the debate over whether concern about a hole in the ozone layer in Antarctic is real or science fiction. There is a growing consensus that efforts must be taken to protect the ozone layer. The issue now is not whether chlorofluorocarbons (CFCs) should be controlled and regulated but how much and how soon. The United States has urged that the production of dangerous CFCs, and any other chemicals that affect the ozone layer, be restricted immediately to current levels and that their use be reduced 95 percent over the next decade. The American position was too strong for many European nations and the Japanese. Negotiations at an international conference on the matter broke down. The breakdown is due in part to a more acute concern for environmental matters in the United States than exists in many countries. Meanwhile CFCs are linked to another environmental problem that equally threatens the world - the Greenhouse Effect. The earth is in a natural warming period, but man could be causing it to become even warmer. The Greenhouse Effect could have a catastrophic impact on mankind, although nothing has been proven yet.

  20. 76 FR 40619 - Approval and Promulgation of Implementation Plans; State of Missouri

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-11

    ... Ambient Air Quality Standards (NAAQS) for ozone. The rationale for this action is explained in this rule... 8-hour ozone NAAQS. The rationale supporting EPA's proposed action is explained in the proposal and... 110(a)(1) and (2) for ozone and PM2.5 NAAQS for various states across the country. Commenters on...

  1. 76 FR 41111 - Approval and Promulgation of Implementation Plans; South Carolina; 110(a)(1) and (2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ... nitrogen oxides (NO X ) as an ozone precursor under the NSR program. See 76 FR 36875. EPA is not taking... maintaining the 75 ppb ozone NAAQS as well as the 1-hour 100 ppb nitrogen oxides NAAQS.'' Response 2: EPA... existing substantive SIP provisions relevant to the 1997 8-hour ozone NAAQS or the new nitrogen dioxide...

  2. 78 FR 34965 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Lima 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Ohio; Lima 1997 8... Implementation Plan (SIP) to replace the previously approved motor vehicle emissions budgets with budgets developed using EPA's Motor Vehicle Emissions Simulator (MOVES) emissions model. Ohio submitted the...

  3. 76 FR 3840 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard for the Delaware...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-21

    ..., consists of: Cecil County in Maryland; Bucks, Chester, Delaware, Montgomery and Philadelphia Counties in... Philadelphia-Wilmin- Atlantic Ci, PA-NJ-MD-DE (Cecil County) to read as follows: Sec. 81.321 Maryland... * * * * * * * Philadelphia-Wilmin-Atlantic Ci, PA-NJ-MD-DE: Cecil County Nonattainment..... Subpart 2/...

  4. 77 FR 28423 - Final Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-14

    ... Areas b. Timing of SIP Submission Under Subpart 2 Classification c. Timing of Attainment Date d. Data.... Required Required No. 182(a)(3)(B)). Subpart 2 RACT for VOCs and NOX (Sec. Not Required Required No. 182(b... Review (Sec. Required Required No. 182(a)(2)(C), (a)(4), (b)(5)). Vehicle I/M (Sec. 182(a)(2)(B),...

  5. 77 FR 43521 - Final Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-25

    ... Designation \\a\\ Category/classification Designated area Date \\1\\ Type Date \\1\\ Type Amador and Calaveras Cos., CA: (Central Mountain Cos.) Amador County Nonattainment 6/13/12 Subpart 2/Moderate. Calaveras County.... * * * * * * * Mariposa and Tuolumne Cos., CA: (Southern Mountain Counties) Mariposa County Nonattainment 6/13/12...

  6. 75 FR 43114 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard in the Baltimore...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... means EPA will not know your identity or contact information unless you provide it in the body of your... in the public docket and made available on the Internet. If you submit an electronic comment, EPA... the Internet and will be publicly available only in hard copy form. Publicly available...

  7. 75 FR 16456 - Adequacy Status of the Beaumont-Port Arthur, TX Maintenance Plan; 8-Hour Ozone Motor Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-01

    ... Emission Budgets for Transportation Conformity Purposes AGENCY: Environmental Protection Agency (EPA... Commission on Environmental Quality (TCEQ) are adequate for transportation conformity purposes. As a result of EPA's finding, the BPA area must use these budgets for future conformity determinations for...

  8. 78 FR 7429 - Adequacy Status of the Dallas-Fort Worth, TX Reasonable Further Progress 8-Hour Ozone Motor...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ... Vehicle Emission Budgets for Transportation Conformity Purposes AGENCY: Environmental Protection Agency... Commission on Environmental Quality (TCEQ) are adequate for transportation conformity purposes. As a result of EPA's finding, the DFW area must use these budgets for future conformity determinations....

  9. 76 FR 28223 - Adequacy Status of the Baton Rouge, Louisiana Maintenance Plan 8-Hour Ozone Motor Vehicle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-16

    ... Emission Budgets for Transportation Conformity Purposes AGENCY: Environmental Protection Agency (EPA... the Louisiana Department of Environmental Quality (LDEQ) are adequate for transportation conformity purposes. As a result of EPA's finding, the Baton Rouge area must use these budgets for future...

  10. 78 FR 34906 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Lima 1997 8-Hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... Motor Vehicle Emissions Simulator (MOVES) emissions model. Ohio submitted the SIP revision request to... consultation process. The Federal Highway Administration and the Ohio Department of Transportation have taken...

  11. 75 FR 47746 - Determination of Nonattainment and Reclassification of the Dallas/Fort Worth 1997 8-hour Ozone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-09

    ... rulemaking for this reclassification, pursuant to section 182(b)(3)(A) of the Act. DATES: Comments must be...'' before submitting comments. E-mail: Mr. Guy Donaldson at donaldson.guy@epa.gov . Please also send a copy... nonattainment area. Section 181(b)(2)(A) of the Act requires that EPA determine, based on the area's...

  12. Ozone Risk Assessment Utilities

    SciTech Connect

    Whitfield, R. G.; Jusko, M. J.; Clemmons, M. A.

    1999-08-10

    ORAMUS is a user-friendly, menu-driven software system that calculates and displays user-selected risk estimates for health effects attributable to short-term exposure to tropospheric ozone. Inputs to the risk assessment are estimates of exposure to ozone and exposure-response relationships to produce overall risk estimates in the form of probability distributions. Three fundamental models are included: headcount risk, benchmark risk, and hospital admissions. Exposure-response relationships are based on results of controlled human exposure studies. Exposure estimates are based on the EPA''s probabilistic national ambient air quality standards (NAAQS) exposure model, pNEM/Osub3, which simulates air quality associated with attainment of alternative NAAQS. Using ORAMUS, risk results for 27 air quality scenarios, air quality in 9 urban areas, 33 health endpoints, and 4 chronic health endpoints can be calculated.

  13. 75 FR 31288 - Approval and Promulgation of Air Quality Implementation Plans; Rhode Island; Determination of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-03

    ... ozone nonattainment area has attained the 1997 8-hour National Ambient Air Quality Standard (NAAQS) for... data that show the area has monitored attainment of the 8-hour ozone NAAQS for the 2006-2008 monitoring period. In addition, quality-assured and certified ozone data for 2009, show that this area continues...

  14. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  15. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  16. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  17. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  18. 40 CFR 51.910 - What requirements for reasonable further progress (RFP) under sections 172(c)(2) and 182 apply...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hour ozone NAAQS? 51.910 Section 51.910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.910 What... nonattainment for the 8-hour ozone NAAQS? (a) What are the general requirements for RFP for an area...

  19. Correlations of beta-aminoisobutyric acid in 8 hour and 24 hour urinary samples determined by dual column gas chromatography.

    PubMed

    Sjölin, K E; Nyholm, K K

    1980-05-01

    The correlations of beta-aminoisobutyric acid values in 8 hour and 24 hour urinary samples from 23 healthy persons were determined. beta-AIB in the 8 hour urinary samples was measured by gas chromatography and the 24 hour excretion was calculated from the results of three 8 hour determinations. Simultaneous determinations of urinary creatinine were performed by Jaffe's reaction. Based on the 8 hour values of urinary beta-AIB the results demonstrated a constant excretion of beta-aminoisobutyric acid within the 24 hour periods in both low and high excretors. The precision in distinguishing low and high 24 hour excretors of beta-AIB by using 8 hour values was 91%. If 8 hour values of beta-AIB were related to creatinine the same precision for this calculated ratio was 96.5%. However, for high excretors of beta-AIB, failures were 24.5% by using the 8 hour excretion of beta-AIB as indicator, but only 6.5% by using the ratio.

  20. Investigating ozone in rural Nevada, USA: Results from the first year of the Nevada Rural Ozone Initiative (NVROI)

    NASA Astrophysics Data System (ADS)

    Gustin, M. S.; Fine, R.; Miller, M. B.; Peterson, C.; Burley, J. D.; Jaffe, D. A.

    2013-12-01

    Ozone has been measured at Great Basin National Park, located in a rural area of eastern Nevada, USA, since 1993. Observations at the Park indicate that the area likely will not be able to meet a revised U.S. National Ambient Air Quality Standard (NAAQS) of ≤ 70 ppbv. Routine ozone monitoring outside of the Park in Nevada has been limited to the two major metropolitan areas in the state, Reno and Las Vegas, and surrounding communities. To address this limitation, a research project, the Nevada Rural Ozone Initiative (NVROI), was put into place. The NVROI goals are to characterize ozone concentrations, and to determine the sources contributing to observed concentrations in Nevada, and regions of the western United States. The first year of the project focused on establishing a network of ozone monitoring sites. Based on the measurements from 5 sites across the state where data were collected from July 2011 to June 2012, seasonal mean (× s) concentrations ranged from 39×15 to 54×9 ppbv (spring); 36×14 to 54×8 ppbv (summer); 27×13 to 44×6 ppbv (fall); and 23×11 to 41×5 ppbv (winter) across the state, with higher mean concentrations observed at the high elevation sites. The average daily maximum 1-hour concentrations of ozone (× s) were similar across these sites ranging from 58×6 to 69×7 ppbv (spring); 53×6 to 62×9 ppbv (summer); 44×7 to 49×6 ppbv (fall); and 37×5 to 45×4 ppbv (winter). Periods of elevated ozone were observed at these 5 NVROI network sites (1513 to 2082 m above sea level (asl)). There were 15, 28, and 81 days with at least one NVROI site experiencing a Maximum Daily 8-hour Average (MDA8) greater than 70, 65, and 60 ppbv, respectively. Events (MDA8 > 60 ppbv) were coincident with (1) passage of frontal systems (spring and early summer events), or (2) the presence of smoke generated by regional wildfires and an area of low pressure over Nevada (summer events). Atmospheric turbulence and vertical lifting is associated with frontal

  1. Transportation Conformity Guidance on the Revocation of the 1997 Primary Annual PM2.5 NAAQS

    EPA Pesticide Factsheets

    This guidance describes how the revocation of the 1997 primary annual PM2.5 national ambient air quality standard (NAAQS) will be implemented and when transportation conformity stops applying for this NAAQS fulfilling EPA's commitment to provide additional

  2. PREDICTING THE IMPACT OF TROPOSPHERIC OZONE ON ECOLOGICAL RESOURCES FOR SETTING NATIONAL AMBIENT AIR QUALITY STANDARDS

    EPA Science Inventory

    The Clean Air Act provides for establishing National Ambient Air Quality Standards (NAAQS) to protect public welfare (including crops, forests, ecosystems, and soils) from adverrse effects of air pollutants, including tropospheric ozone. The formulation of policies is science-bas...

  3. Nitrogen Oxides (NOx) Primary NAAQS REVIEW: Integrated Review Plan

    EPA Science Inventory

    The NOx Integrated Review Plan is the first document generated as part of the National Ambient Air Quality Standards (NAAQS) review process. The Plan presents background information, the schedule for the review, the process to be used in conducting the review, and the key policy...

  4. Policy Assessment for the Particulate Matter NAAQS Review

    EPA Science Inventory

    The policy assessment is a component of the PM NAAQS review that bridges the gap between the scientific assessment contained in the Integrated Science Assessment and the judgments required of the EPA Administration in determining whether it is appropriate to retain or revise the ...

  5. Multi-Model Comparison of Lateral Boundary Contributions to Surface Ozone Over the United States

    EPA Science Inventory

    As the National Ambient Air Quality Standards (NAAQS) for ozone become more stringent, there has been growing attention on characterizing the contributions and the uncertainties in ozone from outside the US to the ozone concentrations within the US. The third phase of the Air Qua...

  6. Multi-model Comparison of Lateral Boundary Contributions to Ozone Concentrations over the United States (CM

    EPA Science Inventory

    As the National Ambient Air Quality Standards (NAAQS) for ozone become more stringent, there has been growing attention on characterizing the contributions and the uncertainties in ozone from outside the US to the ozone concentrations within the US. The third phase of the Air Qua...

  7. Multi-model Comparison of Lateral Boundary Contributions to Ozone Concentrations over the United States

    EPA Science Inventory

    As the National Ambient Air Quality Standards (NAAQS) for ozone become more stringent, there has been growing attention on characterizing the contributions and the uncertainties in ozone from outside the US to the ozone concentrations within the US. The third phase of the Air Qua...

  8. 76 FR 60820 - Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ... AGENCY Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants AGENCY... titled, ``Second External Review Draft Integrated Science Assessment for Ozone and Related Photochemical... ambient air quality standards (NAAQS) for ozone. EPA is releasing this draft document to seek review...

  9. 77 FR 36534 - Third External Review Draft Integrated Science Assessment for Ozone and Related Photochemical...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-19

    ... AGENCY Third External Review Draft Integrated Science Assessment for Ozone and Related Photochemical... External Review Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants'' (EPA/600... Standards (NAAQS) for ozone. EPA is releasing this draft document to seek review by the Clean Air...

  10. 75 FR 2935 - Extension of Deadline for Promulgating Designations for the 2008 Ozone National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ... Protection Agency 40 CFR Parts 50, 58 and 81 Ozone National Ambient Air Quality Standards; Final Rule and... Designations for the 2008 Ozone National Ambient Air Quality Standards AGENCY: Environmental Protection Agency... promulgating initial area designations for the ozone national ambient air quality standards (NAAQS) that...

  11. 75 FR 45075 - Federal Implementation Plans To Reduce Interstate Transport of Fine Particulate Matter and Ozone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... Interstate Transport of Fine Particulate Matter and Ozone AGENCY: Environmental Protection Agency (EPA... Matter and Ozone'' (Transport Rule) which is published elsewhere in today's issue of the Federal Register... ozone NAAQS. Public hearing: The proposal for which EPA is holding the public hearings is...

  12. 76 FR 10893 - Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-28

    ... AGENCY Draft Integrated Science Assessment for Ozone and Related Photochemical Oxidants AGENCY... review draft of a document titled, ``First External Review Draft Integrated Science Assessment for Ozone... review of the national ambient air quality standards (NAAQS) for ozone. EPA is releasing this...

  13. AIR QUALITY CRITERIA FOR OZONE AND RELATED PHOTOCHEMICAL OXIDANTS

    EPA Science Inventory

    The Clean Air Act requires periodic (5-year) update revision of criteria and National Ambient Air Quality Standards (NAAQS) for Ozone. The previous revision of the criteria contained in the Air Quality Criteria Document (AQCD) for Ozone and Related Photochemical Oxidants was co...

  14. Effects of nitrogen oxide emission controls on Eastern US surface ozone: A comparison between urban cores and rural background sites

    NASA Astrophysics Data System (ADS)

    Rieder, Harald E.; Fiore, Arlene M.

    2016-04-01

    Nitrogen oxide (NOx) emission controls have led to improved air quality over the past two decades, particularly over the Eastern US. In recent work we quantified the effects of the efforts to abate surface ozone (O3) pollution under the NOx State Implementation Plan (NOx SIP Call) for Eastern US background sites (available from the Clean Air Status and Trends Network (CASTNET)) using methods from statistical extreme value theory (Rieder et al., 2013). Our analysis showed that the number of summer (JJA) days above the US national ambient air quality standard (NAAQS) declined on average by a factor of two between 1988-1998 and 1999-2009 and that probabilistic 1-yr O3 return values declined by about 10 ppb between these two time periods. Here we extend the analysis to observations available from the US EPA Air Quality System (AQS), comprising sites ranging from polluted urban cores to rural sites. We focus on changes in (i) the seasonal and annual average number of days with maximum daily 8-hour average surface O3 above the NAAQS and (ii) probabilistic O3 return values following the NOx SIP Call. Particular focus is given on similarities and differences in surface O3 responses on regional to local level and on contrasting urban cores and rural background sites. References: Rieder H.E., Fiore A.M., Polvani L.M., Lamarque J.-F., Fang Y. (2013): Changes in the frequency and return level of high ozone pollution events over the Eastern United States following emission controls, Environ. Res. Lett., 8, 014012, 2013.

  15. PREDICTING THE IMPACT OF TROPOSPHERIC OZONE ON PLANTS AND ECOSYSTEMS AS A BASIS FOR SETTING NATIONAL AIR QUALITY STANDARDS

    EPA Science Inventory

    The Clean Air Act provides for establishing National Ambient Air Quality Standards (NAAQS) to protect public welfare (including crops, forests, ecosystems, and soils) from adverse effects of air pollutants, including tropospheric ozone. The formulation of policies is science-base...

  16. 75 FR 36316 - Approval and Promulgation of Air Quality Implementation Plans; Louisiana; Determination of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-25

    ...-hour ozone nonattainment area has attained the 1997 8-hour National Ambient Air Quality Standard (NAAQS... monitoring data that show the area has monitored attainment of the 1997 8-hour ozone NAAQS since the 2006... requirements for this area to submit an attainment demonstration, a reasonable further progress...

  17. 40 CFR 52.147 - Interstate transport.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... SIP submitted on May 24, 2007 meets the requirements of Clean Air Act section 110(a)(2)(D)(i)(I... deterioration of air quality, only) for the 1997 8-hour ozone and 1997 PM2.5 NAAQS. (b) Disapproval. The SIPs... the 1997 8-hour ozone and 1997 PM2.5 NAAQS. (c) Approval. The SIP submitted on October 14, 2009...

  18. 76 FR 70656 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-15

    ... area (hereafter referred to as the ``bi-state Charlotte Area'') is composed of Cabarrus, Gaston...-2010 showing that the bi-state Charlotte Area has monitored attainment of the 1997 8-hour ozone NAAQS... planning state implementation plans (SIPs) related to attainment of the 1997 8-hour ozone NAAQS for the...

  19. 75 FR 14077 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-24

    ... submitted on February 24, 2009, from the State of Arkansas to redesignate the Arkansas portion of the bi-state Memphis, Tennessee-Arkansas 8-hour ozone nonattainment area (hereafter referred to ] as the ``bi... (NAAQS). The bi-state Memphis 1997 8-hour ozone NAAQS nonattainment area is composed of Crittenden...

  20. 76 FR 77950 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-15

    ... is the air quality in the Atlanta area for the 1997 8-hour ozone NAAQS for the 2008-2010 monitoring... the 1997 8-hour ozone national ambient air quality standards (NAAQS) by its applicable attainment date... air quality as of the attainment date, whether the area attained the standard by that date.''...

  1. Multi-model Comparison of Lateral Boundary Contributions to Ozone Concentrations over the United States (CMAS Presentation)

    EPA Science Inventory

    As the National Ambient Air Quality Standards (NAAQS) for ozone become more stringent, there has been growing attention on characterizing the contributions and the uncertainties in ozone from outside the US to the ozone concentrations within the US. The third phase of the Air Qua...

  2. 75 FR 1566 - Public Hearings for Reconsideration of the 2008 National Ambient Air Quality Standards for Ozone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-12

    ... Ambient Air Quality Standards for Ozone AGENCY: Environmental Protection Agency (EPA). ACTION... proposed rule, ``Reconsideration of the 2008 National Ambient Air Quality Standards for Ozone,'' which was... the following Web site: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html for the...

  3. 75 FR 8571 - Approval and Promulgation of Air Quality Implementation Plans; Rhode Island; Determination of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-25

    ...) moderate 1997 8-hour ozone nonattainment area has attained the 1997 8-hour National Ambient Air Quality... air monitoring data that shows the area has monitored attainment of the 8-hour ozone NAAQS for the 2006-2008 monitoring period. In addition, preliminary ozone data for 2009 show the area continues...

  4. National Primary and Secondary Ambient Air Quality Standards (NAAQS) for Lead (Pb) and Implementation Plans for Lead NAAQS: 1978 Final Rule (43 FR 46246 & 46264)

    EPA Pesticide Factsheets

    This document is a copy of the Federal Register publication of the October 5, 1978 Final Rules for National Primary and Secondary Ambient Air Quality Standards for Lead (Pb) and Implementation Plans for Lead (Pb) NAAQS.

  5. 40 CFR 52.353 - Section 110(a)(2) infrastructure requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... provides the state of Colorado's SIP provisions for meeting the requirements of CAA Section 110(a)(1) and (2) relevant to the 1997 8-hour ozone NAAQS. The State's 1997 Ozone Infrastructure SIP is...

  6. 40 CFR 52.353 - Section 110(a)(2) infrastructure requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... provides the state of Colorado's SIP provisions for meeting the requirements of CAA Section 110(a)(1) and (2) relevant to the 1997 8-hour ozone NAAQS. The State's 1997 Ozone Infrastructure SIP is...

  7. Air Quality Criteria for Ozone and Related Photochemical Oxidants (Final Report, 2006)

    EPA Science Inventory

    In February 2006, EPA released the final document, Air Quality Criteria for Ozone and Other Photochemical Oxidants. Tropospheric or surface-level ozone (O3) is one of six major air pollutants regulated by National Ambient Air Quality Standards (NAAQS) under the U.S...

  8. Ozone (O3) Standards - Other Technical Documents from the Current Review

    EPA Pesticide Factsheets

    These memoranda were each sent in to the Ozone NAAQS Review Docket, EPA-HQ-OAR-2008-0699, after the proposed rule was published. They present technical data on the methods, monitoring stations, and metrics used to estimate ozone concentrations.

  9. Fact Sheets on Review of National Ambient Air Quality Standards for Ozone Staff Papers

    EPA Pesticide Factsheets

    The second draft Staff Paper points to an expanded body of health effects evidence suggesting a wide range of adverse health effects associated with exposure to ambient ozone. This is part of the process for review of the NAAQS for ground-level ozone.

  10. 77 FR 26441 - Approval and Promulgation of Implementation Plans; North Carolina; Charlotte; Ozone 2002 Base...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-04

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Implementation Plans; North Carolina; Charlotte; Ozone... rule. SUMMARY: EPA is taking direct final action to approve the ozone 2002 base year emissions... ozone attainment demonstration that was submitted for the 1997 8-hour ozone national ambient air...

  11. Cerebral blood flow determination within the first 8 hours of cerebral infarction using stable xenon-enhanced computed tomography

    SciTech Connect

    Hughes, R.L.; Yonas, H.; Gur, D.; Latchaw, R.

    1989-06-01

    Cerebral blood flow mapping with stable xenon-enhanced computed tomography (Xe/CT) was performed in conjunction with conventional computed tomography (CT) within the first 8 hours after the onset of symptoms in seven patients with cerebral infarction. Six patients had hemispheric infarctions, and one had a progressive brainstem infarction. Three patients with very low (less than 10 ml/100 g/min) blood flow in an anatomic area appropriate for the neurologic deficit had no clinical improvement by the time of discharge from the hospital; follow-up CT scans of these three patients confirmed infarction in the area of very low blood flow. Three patients with moderate blood flow reductions (15-45 ml/100 g/min) in the appropriate anatomic area had significant clinical improvement from their initial deficits and had normal follow-up CT scans. One patient studied 8 hours after stroke had increased blood flow (hyperemia) in the appropriate anatomic area and made no clinical recovery.

  12. 40 CFR 52.172 - Approval status.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) 1997 8-hour ozone NAAQS: The SIPs submitted December 17, 2007 and March 28, 2008 are partially... Greenhouse Gas emissions. (c) 1997 PM2.5 NAAQS: The SIP submitted March 28, 2008 is disapproved for CAA elements 110(a)(2)(C), (D)(ii), and (J). (d) 2006 PM2.5 NAAQS: The SIPs submitted March 28, 2008...

  13. 77 FR 6711 - Approval and Promulgation of Implementation Plans; Arkansas; Infrastructure Requirements for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-09

    ... and the 1997 and 2006 fine particulate matter (PM 2.5 ) national ambient air quality standards (NAAQS... deterioration of air quality, with regard to the 1997 8-hour ozone NAAQS and the 2006 PM 2.5 NAAQS. The partial... restricted by statute. Certain other material, such as copyrighted material, will be publicly available...

  14. Integrated Science Assessment (ISA) of Ozone and Related ...

    EPA Pesticide Factsheets

    EPA has released the Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Second External Review Draft) for independent peer review and public review. This draft document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision regarding the adequacy of the current national ambient air quality standards for ozone to protect human health, public welfare, and the environment. Critical evaluation and integration of the evidence on health and environmental effects of ozone to provide scientific support for the review of the NAAQS for ozone.

  15. Integrated Science Assessment (ISA) of Ozone and Related ...

    EPA Pesticide Factsheets

    EPA has released the Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Third External Review Draft) for independent peer review and public review. This draft document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision regarding the adequacy of the current national ambient air quality standards for ozone to protect human health, public welfare, and the environment. Critical evaluation and integration of the evidence on health and environmental effects of ozone to provide scientific support for the review of the NAAQS for ozone.

  16. Integrated Science Assessment (ISA) of Ozone and Related ...

    EPA Pesticide Factsheets

    EPA announced that the First External Review Draft of the Integrated Science Assessment for Ozone and Related Photochemical Oxidants has been made available for independent peer review and public review. This draft document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision regarding the adequacy of the current national ambient air quality standards for ozone to protect human health, public welfare, and the environment. Critical evaluation and integration of the evidence on health and environmental effects of ozone to provide scientific support for the review of the NAAQS for ozone.

  17. 2013 Final Report: Integrated Science Assessment of Ozone ...

    EPA Pesticide Factsheets

    EPA is announcing the availability of the Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Final Report). This document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision regarding the adequacy of the current national ambient air quality standards for ozone to protect human health, public welfare, and the environment. Critical evaluation and integration of the evidence on health and environmental effects of ozone to provide scientific support for the review of the NAAQS for ozone.

  18. Integrated Science Assessment (ISA) of Ozone and Related ...

    EPA Pesticide Factsheets

    EPA announced the availability of the final report, Integrated Science Assessment of Ozone and Related Photochemical Oxidants. This document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision regarding the adequacy of the current national ambient air quality standards for ozone to protect human health, public welfare, and the environment. Critical evaluation and integration of the evidence on health and environmental effects of ozone to provide scientific support for the review of the NAAQS for ozone.

  19. 77 FR 64036 - Determination of Attainment of the 1-Hour Ozone National Ambient Air Quality Standards in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-18

    ...-hour ozone NAAQS or standard), and to exclude certain 2008 data caused by wildfire exceptional events... occurred due to wildfire exceptional events in 2008.\\1\\ In making its proposed determination, EPA proposed... ozone exceptional events that are caused by wildfires. These air quality determinations were...

  20. 2006 Particulate Matter (PM) National Ambient Air Quality Standards (NAAQS) Infrastructure Actions

    EPA Pesticide Factsheets

    Read about the EPA's infrastructure actions for the 2006 PM NAAQS. These actions are regarding states' failure to submit SIPs addressing various parts of the standards. Here you can read the federal register notices,and fact sheets

  1. Lead (Pb) National Ambient Air Quality Standards (NAAQS) Implementation Guidance Documents

    EPA Pesticide Factsheets

    This page contains implementation guidance documents for the 1978 and 2008 Lead (Pb) NAAQS. Some of the topics covered are: RACM/RACT, RFP, new source review, designations, emissions inventories, attainment dates, and transition policy

  2. Final Regulatory Impact Analysis (RIA) for the NO2 National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    This RIA provides illustrative estimates, as of January 2010, of the incremental costs and monetized human health benefits of attaining the revised NO2 NAAQS within the the existing community-wide monitoring network of 409 monitors.

  3. Table of Historical Nitrogen Dioxide National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    See the history of limits to the level of nitrogen dioxide (NO2) in ambient air, set through the NAAQS review and rulemaking process under the Clean Air Act. This includes both primary and secondary standards.

  4. 2008 Lead (Pb) National Ambient Air Quality Standards (NAAQS) Implementation Actions

    EPA Pesticide Factsheets

    Read about the EPA's infrastructure actions for the 2008 lead NAAQS. These actions are regarding states' failure to submit SIPs addressing various parts of the standards. Here you can read the federal register notices, fact sheets, and the docket folder.

  5. Table of Historical Sulfur Dioxide National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    See the history of limits to the level of sulfur dioxide (SO2) in ambient air, set through the NAAQS review and rulemaking process under the Clean Air Act. This includes both primary and secondary standards.

  6. Are the elements of the proposed ozone National Ambient Air Quality Standards informed by the best available science?

    PubMed

    Goodman, Julie E; Sax, Sonja N; Lange, Sabine; Rhomberg, Lorenz R

    2015-06-01

    The United States Environmental Protection Agency (US EPA) issues National Ambient Air Quality Standards (NAAQS) for six criteria pollutants, including ozone. Each standard has four elements: an indicator, level, averaging time, and form. Ozone levels (i.e., air concentrations) alone in scientific studies are not directly comparable to the "level" element of the NAAQS because the standard considers the level in the context of its relation to the remaining elements. Failure to appreciate this has led to misunderstandings regarding NAAQS that would be health-protective. This can be seen with controlled human ozone exposure studies, which often involved small numbers of people exercising quasi-continuously for a long duration at an intensity not common in the general population (and unlikely achievable by most sensitive individuals), under worst-case exposure profiles. In addition, epidemiology studies have used different averaging times and have had methodological limitations that may have biased results. Such considerations can make it difficult to compare ozone levels and results across studies and to appropriately apply them in a NAAQS evaluation. Relating patterns and circumstances of exposure, and exposure measurements, to all elements of the NAAQS can be challenging, but if US EPA fully undertook this, it would be evident that available evidence does not indicate that proposed lower ozone standards would be more health protective than the current one.

  7. 75 FR 31290 - Approval and Promulgation of State Implementation Plan Revisions; State of North Dakota; Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-03

    ... Ozone NAAQS: ``Significant Contribution to Nonattainment'' and ``Interference With Prevention of... requirements of Clean Air Act section 110(a)(2)(D)(i) for the 1997 PM 2.5 and 8-hour ozone National Ambient Air..., address the requirements of Clean Air Act section 110(a)(2)(D)(i) for the 1997 8-hour ozone and 1997 PM...

  8. 77 FR 30902 - Partial Approval and Promulgation of Implementation Plans; Washington: Infrastructure...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ...) promulgated for ozone on July 18, 1997. EPA finds that the current Washington SIP meets the following 110(a)(2) infrastructure elements for the 1997 8-hour ozone NAAQS: (A), (B), (C), (D)(ii), (E), (F), (G), (H), (J), (K), (L.... Statutory and Executive Order Reviews I. Background On July 18, 1997, EPA promulgated a new NAAQS for...

  9. 77 FR 25363 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-30

    ... ambient air quality data from the 2007-2009 monitoring period which show that the St. Louis area has... Attainment Date for the 1997 Ozone National Ambient Air Quality Standard (NAAQS) AGENCY: Environmental... area'') attained the 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS) by the...

  10. 75 FR 33174 - Approval and Promulgation of Implementation Plans; New Mexico; Interstate Transport of Pollution

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-11

    ... version of CAMx that eliminated the excessive downward transport of ozone from the top layers of the model...) for the 1997 ozone National Ambient Air Quality Standard (NAAQS) and the 1997 PM 2.5 NAAQS. This SIP... emissions from within New Mexico from contributing significantly to nonattainment of the 1997 8-hour...

  11. 40 CFR 52.1991 - Section 110(a)(2) infrastructure requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... elements for the 1997 8-hour ozone NAAQS: (A), (B), (C), (D)(ii), (E), (F), (G), (H), (J), (K), (L), and (M... the 2008 ozone NAAQS: (A), (B), (C), (D)(ii), (E), (F), (G), (H), (J), (K), (L), and (M). The EPA also... of the user, the added text is set forth as follows: § 52.1991 Section 110(a)(2)...

  12. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  13. 40 CFR 52.2043 - Control strategy for maintenance plans: ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: ozone. 52.2043 Section 52.2043 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Control strategy for maintenance plans: ozone. (a) As of December 26, 2013, EPA approves the following... (VOCs) for the Lancaster 1997 8-Hour Ozone Maintenance Area submitted by the Secretary of...

  14. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  15. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  16. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  17. 78 FR 9596 - Approval and Promulgation of Implementation Plans; New Jersey and New York Ozone Attainment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Implementation Plans; New Jersey and New York Ozone... Environmental Protection Agency (EPA) is approving the ozone attainment demonstration portion of comprehensive... requirements for attaining the 1997 8-hour ozone national ambient air quality standard. EPA is approving...

  18. 77 FR 73570 - Approval and Promulgation of Implementation Plans; New Jersey and New York Ozone Attainment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-11

    ...-0840, FRL-9761-7] Approval and Promulgation of Implementation Plans; New Jersey and New York Ozone... Environmental Protection Agency (EPA) is proposing action on the ozone attainment demonstration portion of... requirements for attaining the 1997 8-hour ozone national ambient air quality standard. EPA is proposing...

  19. 40 CFR 52.2052 - Motor vehicle emissions budgets for Pennsylvania ozone areas.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Pennsylvania ozone areas. 52.2052 Section 52.2052 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...) Pennsylvania § 52.2052 Motor vehicle emissions budgets for Pennsylvania ozone areas. (a) As of December 26... nitrogen oxides (NOX) and volatile organic compounds (VOCs) for the Lancaster 1997 8-Hour Ozone...

  20. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone (O3) is 0.075 parts...

  1. Ground-level Ozone (Smog) Information | New England | US ...

    EPA Pesticide Factsheets

    2017-02-16

    Ground-level ozone presents a serious air quality problem in New England. In 2008, EPA revised the ozone standard to a level of 0.075 parts per million, 8-hour average. Over the last 5 years (2006 through 2010), there have been an average of 31 days per summer when New England's air exceeded this standard.

  2. Ground-level Ozone (Smog) Information | New England | US ...

    EPA Pesticide Factsheets

    2017-04-10

    Ground-level ozone presents a serious air quality problem in New England. In 2008, EPA revised the ozone standard to a level of 0.075 parts per million, 8-hour average. Over the last 5 years (2006 through 2010), there have been an average of 31 days per summer when New England's air exceeded this standard.

  3. Pulmonary Function Response to Exposure to Low Concentration Ozone in Young Adults: Inter-comparison among Studies and Meta-Analysis

    EPA Science Inventory

    Rationale: It is well established that moderate ozone exposures induce decrements in spirometry volume and respiratory symptoms in healthy young adults. However, studies for low concentration ozone near the current NAAQS standard (0.070 ppm) are limited to only a few and their co...

  4. Evaluation of emission control strategies to reduce ozone pollution in the Paso del Norte region using a photochemical air quality modeling system

    NASA Astrophysics Data System (ADS)

    Valenzuela, Victor Hugo

    Air pollution emissions control strategies to reduce ozone precursor pollutants are analyzed by applying a photochemical modeling system. Simulations of air quality conditions during an ozone episode which occurred in June, 2006 are undertaken by increasing or reducing area source emissions in Ciudad Juarez, Chihuahua, Mexico. Two air pollutants are primary drivers in the formation of tropospheric ozone. Oxides of nitrogen (NOx) and volatile organic compounds (VOC) undergo multiple chemical reactions under favorable meteorological conditions to form ozone, which is a secondary pollutant that irritates respiratory systems in sensitive individuals especially the elderly and young children. The U.S. Environmental Protection Agency established National Ambient Air Quality Standards (NAAQS) to limit ambient air pollutants such as ozone by establishing an 8-hour average concentration of 0.075 ppm as the threshold at which a violation of the standard occurs. Ozone forms primarily due reactions in the troposphere of NOx and VOC emissions generated primarily by anthropogenic sources in urban regions. Data from emissions inventories indicate area sources account for ˜15 of NOx and ˜45% of regional VOC emissions. Area sources include gasoline stations, automotive paint bodyshops and nonroad mobile sources. Multiplicity of air pollution emissions sources provides an opportunity to investigate and potentially implement air quality improvement strategies to reduce emissions which contribute to elevated ozone concentrations. A baseline modeling scenario was established using the CAMx photochemical air quality model from which a series of sensitivity analyses for evaluating air quality control strategies were conducted. Modifications to area source emissions were made by varying NOx and / or VOC emissions in the areas of particular interest. Model performance was assessed for each sensitivity analysis. Normalized bias (NB) and normalized error (NE) were used to identify

  5. Ozone concentrations near roadways - results of a field study in Cincinnati, Ohio

    SciTech Connect

    Johnson, T.; Weaver, M.; Mozier, J.

    1997-12-31

    In evaluating alternative versions of the National Ambient Air Quality Standard (NAAQS) for ozone, the U.S. Environmental Protection Agency uses the probabilistic NAAQS Exposure Model (pNEM/O3) to estimate the relative ozone exposures of urban populations. This model simulates the movement of susceptible population groups through various microenvironmental (ME) settings and uses ambient monitoring data and ME adjustments to estimate a sequence of exposures for each group. One ME is defined as {open_quotes}outdoors near roadway.{close_quotes} To obtain an improved modeling database for this ME, researchers conducted a two-phase field study in Cincinnati, Ohio during the summers of 1994 and 1995. Technicians measured ozone and nitric oxide from automobile exhaust at upwind and downwind locations near a variety of roadways in areas with historically high ozone levels. During the 1995 phase, measurements were taken at 2 and 10-meter elevations along a downwind pathway at right angles to each roadway. Statistical analyses of the ozone concentrations measured at these locations indicated that height above the ground was always a very significant predictor of ozone, with ozone levels at 10 m above the ground tending to be higher than those at 2 m. Ozone varied significantly as a quadratic function of distance from the road at 2 m, but not at 10 m. Downwind ozone decreased with increasing levels of downwind NO, consistent with the hypothesis that ozone is scavenged by NO from automobile exhaust. Downwind ozone levels increased with increasing temperature.

  6. THE PASSIVE OZONE NETWORK IN DALLAS (POND CONCEPT) - A MODELING OPPORTUNITY WITH COMMUNITY INVOLVEMENT

    EPA Science Inventory

    Despite tremendous efforts towards regulating and controlling tropospheric ozone (O3) formation, over 70 million people currently live in U.S. counties which exceed the National Ambient Air Quality Standard (NAAQS) set for 03. These high 03 concentrations alone cost the U.S. ap...

  7. Air Quality Criteria for Ozone and Related Photochemical Oxidants (2006 Final)

    EPA Science Inventory

    Tropospheric or surface-level ozone (O3) is one of six major air pollutants regulated by National Ambient Air Quality Standards (NAAQS) under the U.S. Clean Air Act. As mandated by the Clean Air Act, the U.S. Environmental Protection Agency (EPA) must periodically review t...

  8. 75 FR 42085 - Workshop To Review Initial Health Effects Draft Materials for the Ozone (O3

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-20

    ... of the review of the air quality criteria and National Ambient Air Quality Standard (NAAQS) for Ozone... observers on a first-come, first-served basis up to the limits of available space. DATES: The workshop will...) of the Clean Air Act requires the U.S. Environmental Protection Agency (EPA) to conduct...

  9. EPA's Reference and Equivalent Supporting NAAQS Implementation through Methods Research Program: Research, Development, and Analysis

    EPA Science Inventory

    . To assess the ambient concentration levels of the six criteria air pollutants regulated by National Ambient Air Quality Standards (NAAQS), the U.S. Environmental Protection Agency (EPA) developed a systematic framework of: (a) field measurements of ambient air pollutant levels ...

  10. Sulfur Dioxide (SO2) Primary NAAQS Review: Integrated Review Plan - Advisory with CASAC

    EPA Science Inventory

    The SO2 Integrated Review Plan is the first document generated as part of the National Ambient Air Quality Standards (NAAQS) review process. The Plan presents background information, the schedule for the review, the process to be used in conducting the review, and the key policy-...

  11. 40 CFR 58.30 - Special considerations for data comparisons to the NAAQS.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-scale impact sites are only eligible for comparison to the 24-hour PM2.5 NAAQS. For example, if the PM2... average 24-hour concentrations representative of a smaller than neighborhood spatial scale, then data from... are cases where certain population-oriented microscale or middle scale PM2.5 monitoring sites...

  12. 40 CFR 58.30 - Special considerations for data comparisons to the NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... Consistent with appendix D to this part, section 4.7.1, when micro- or middle-scale PM 2.5 monitoring sites... but rather of relatively unique micro-scale, or localized hot spot, or unique middle-scale impact... monitors are eligible for comparison to the 24-hour PM 2.5 NAAQS. For example, if a micro- or...

  13. 40 CFR 58.30 - Special considerations for data comparisons to the NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-scale impact sites are only eligible for comparison to the 24-hour PM2.5 NAAQS. For example, if the PM2... average 24-hour concentrations representative of a smaller than neighborhood spatial scale, then data from... are cases where certain population-oriented microscale or middle scale PM2.5 monitoring sites...

  14. 40 CFR 51.1008 - Emission inventory requirements for the PM2.5 NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PM2.5 NAAQS. 51.1008 Section 51.1008 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of PM2.5 National Ambient Air Quality Standards § 51.1008 Emission inventory... demonstration required under § 51.1007 and for meeting RFP requirements under § 51.1009. As determined on...

  15. 40 CFR 51.1008 - Emission inventory requirements for the PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PM2.5 NAAQS. 51.1008 Section 51.1008 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions for Implementation of PM2.5 National Ambient Air Quality Standards § 51.1008 Emission inventory... demonstration required under § 51.1007 and for meeting RFP requirements under § 51.1009. As determined on...

  16. 40 CFR 58.30 - Special considerations for data comparisons to the NAAQS.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) AMBIENT AIR QUALITY SURVEILLANCE National Air Monitoring Stations (NAMS...) There are two forms of the PM2.5 NAAQS described in part 50 of this chapter. The PM2.5 monitoring site....5 monitoring site is adjacent to a unique dominating local PM2.5 source or can be shown to...

  17. 77 FR 65151 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-25

    ...EPA is proposing to approve: the State of New Hampshire's request to redesignate the Boston-Manchester-Portsmouth (SE), New Hampshire moderate 8-hour ozone nonattainment area to attainment for the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS); a State Implementation Plan (SIP) revision containing a 10-year maintenance plan for this area; a 2008 comprehensive emissions......

  18. 76 FR 6590 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Determination of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-07

    ... (see 40 CFR 51.918), if EPA issues a determination that an area is attaining the relevant standard... the Pittsburgh Area is attaining the 1997 8-hour ozone NAAQS. In accordance with 40 CFR 51.918, if EPA...; Determination of Attainment for the Pittsburgh-Beaver Valley 8-Hour Ozone Nonattainment Area...

  19. 40 CFR 51.912 - What requirements apply for reasonably available control technology (RACT) and reasonably...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.912 What requirements apply for... than 27 months after designation for the 8-hour ozone NAAQS, except that for a State subject to...

  20. 75 FR 62470 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... Quality Planning Purposes; Tennessee: Knoxville; Determination of Attaining Data for the 1997 8-Hour Ozone... 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS) has attained these standards based on quality assured, quality controlled monitoring data from 2007 through 2009. The Knoxville 1997...

  1. 77 FR 37812 - Approval and Promulgation of Air Quality Implementation Plans; South Carolina; Emissions Statements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-25

    ... bi-state Charlotte- Gastonia-Rock Hill, North Carolina-South Carolina 1997 8-hour ozone nonattainment... area (hereafter referred to as the ``bi-state Charlotte Area'') is comprised of Cabarrus, Gaston... the 1997 8-hour ozone NAAQS for its portion of the bi-state Charlotte Area. On November 15, 2011,...

  2. 75 FR 56 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-04

    ... Conservation (TDEC), Air Pollution Control Division, to redesignate the Tennessee portion of the bi-state Memphis, Tennessee-Arkansas 8-hour ozone nonattainment area (hereafter referred to as the ``bi-state...). The bi-state Memphis 1997 8-hour ozone NAAQS nonattainment area is composed of Shelby...

  3. 76 FR 54465 - Proposed Settlement Agreement, Clean Air Act Citizen Suit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... given of a proposed settlement agreement to address a lawsuit filed by Sierra Club and WildEarth..., Arizona, Florida and Georgia with regard to the 1997 8-hour ozone National Ambient Air Quality Standards..., Nevada, North Carolina, Tennessee, and Arizona with regard to the 1997 8-hour ozone NAAQS. The...

  4. ORAMUS(WINDOWS). Ozone Risk AssessMent Utilities

    SciTech Connect

    Whitfield, R.G.; Jusko, M.J.; Biller, W.F.

    1998-12-01

    ORAMUS is a user-friendly, menu-driven software system that calculates and displays user-selected risk estimates for health effects attributable to short-term exposure to tropospheric ozone. Inputs to the risk assessment are estimates of exposure to ozone and exposure-response relationships to produce overall risk estimates in the form of probability distributions. Three fundamental models are included: headcount risk, benchmark risk, and hospital admissions. Exposure-response relationships are based on results of controlled human exposure studies. Exposure estimates are based on the EPA`s probabilistic national ambient air quality standards (NAAQS) exposure model, pNEM/Osub3, which simulates air quality associated with attainment of alternative NAAQS. Using ORAMUS, risk results for 27 air quality scenarios, air quality in 9 urban areas, 33 health endpoints, and 4 chronic health endpoints can be calculated.

  5. ORAMUS(DOS). Ozone Risk AssessMent Utilities

    SciTech Connect

    Whitfield, R.G.; Jusko, M.J.; Biller, W.F.

    1998-12-01

    ORAMUS is a user-friendly, menu-driven software system that calculates and displays user-selected risk estimates for health effects attributable to short-term exposure to tropospheric ozone. Inputs to the risk assessment are estimates of exposure to ozone and exposure-response relationships to produce overall risk estimates in the form of probability distributions. Three fundamental models are included: headcount risk, benchmark risk, and hospital admissions. Exposure-response relationships are based on results of controlled human exposure studies. Exposure estimates are based on the EPA`s probabilistic national ambient air quality standards (NAAQS) exposure model, pNEM/Osub3, which simulates air quality associated with attainment of alternative NAAQS. Using ORAMUS, risk results for 27 air quality scenarios, air quality in 9 urban areas, 33 acute health endpoints, and 4 chronic health endpoints can be calculated.

  6. Projected changes in high ozone pollution events over the Eastern United States over the 21st century

    NASA Astrophysics Data System (ADS)

    Fiore, A. M.; Rieder, H.; Horowitz, L. W.; Naik, V.

    2013-12-01

    Over the past few decades, thresholds for the United States (US) National Ambient Air Quality Standard (NAAQS) for ozone (O3), established to protect public health and welfare, have been lowered repeatedly. We recently applied methods from extreme value theory (EVT) to maximum daily 8-hour average ozone (MDA8 O3) observed by the Clean Air Status and Trends Network (CASTNet) to quantify the significant decline in both frequency and magnitude of high O3 pollution events over the Eastern US from 1988 to 2009. These improvements to Eastern US air quality have been reported in prior studies and result from changes in air quality regulations and subsequent control measures (e.g., the 'NOx SIP Call') as demonstrated by our analysis of 1-year and 5-year return levels. Here we extend this analysis to future projections of high O3 pollution events spanning the course of the 21st century. To this aim, we analyze simulations from the GFDL CM3 chemistry-climate model under selected Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5 (representing a moderate and strong climate warming with a global mean temperature change by 2100 compared to present day of +2.3K and +4.5K, respectively). Under both scenarios, NOx emissions decrease by ~80% over North America by 2100 under the assumption of aggressive ozone pollution controls. A third scenario, termed RCP4.5_WMGG, in which well-mixed greenhouse gases follow the RCP4.5 scenario but O3 and aerosol precursor emissions are held at 2005 levels, enables us to isolate the role of climate change from that of emission reductions. As we find a positive bias in GFDL CM3 MDA8 O3 compared to the Eastern US CASTNet O3 measurements during summer (a common feature in the current generation of models), we develop a correction method based on quantile-mapping. This bias correction effectively removes the model bias while preserving the temporal changes in MDA8 O3 as simulated under different RCPs over the course of the 21st

  7. Projected changes in high ozone pollution events over the Eastern United States over the 21st century

    NASA Astrophysics Data System (ADS)

    Rieder, Harald E.; Fiore, Arlene M.; Horrowitz, Larry W.; Naik, Vaishali

    2014-05-01

    Over the past few decades, thresholds for the United States (US) National Ambient Air Quality Standard (NAAQS) for ozone (O3), established to protect public health and welfare, have been lowered repeatedly. We recently applied methods from extreme value theory (EVT) to maximum daily 8-hour average ozone (MDA8 O3) observed by the Clean Air Status and Trends Network (CASTNet) to quantify the significant decline in both frequency and magnitude of high O3 pollution events over the Eastern US from 1988 to 2009. These improvements to Eastern US air quality have been reported in prior studies and result from changes in air quality regulations and subsequent control measures (e.g., the "NOx SIP Call") as demonstrated by our analysis of 1-year and 5-year return levels. Here we extend this analysis to future projections of high O3 pollution events spanning the course of the 21st century. To this aim, we analyze simulations from the GFDL CM3 chemistry-climate model under selected Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5 (representing a moderate and strong climate warming with a global mean temperature change by 2100 compared to present day of +2.3K and +4.5K, respectively). Under both scenarios, NOx emissions decrease by ~80% over North America by 2100 under the assumption of aggressive ozone pollution controls. A third scenario, termed RCP4.5_WMGG, in which well-mixed greenhouse gases follow the RCP4.5 scenario but O3 and aerosol precursor emissions are held at 2005 levels, enables us to isolate the role of climate change from that of emission reductions. As we find a positive bias in GFDL CM3 MDA8 O3 compared to the Eastern US CASTNet O3 measurements during summer (a common feature in the current generation of models), we develop a correction method based on quantile-mapping. This bias correction effectively removes the model bias while preserving the temporal changes in MDA8 O3 as simulated under different RCPs over the course of the 21st

  8. The 1996 Paso del Norte Ozone Study: analysis of meteorological and air quality data that influence local ozone concentrations.

    PubMed

    MacDonal, C P; Roberts, P T; Main, H H; Dye, T S; Coe, D L; Yarbrough, J

    2001-08-10

    The 1996 Paso del Norte Ozone Study and subsequent data analyses were implemented to develop an understanding of the chemical and physical processes which lead to high concentrations of ozone in the Paso del Norte study area which includes El Paso County, Texas, Sunland Park, New Mexico, and Ciudad Juárez, Mexico. Both the data and data analysis results are being used to support photochemical grid modeling. El Paso County and Sunland Park fail to meet the National Ambient Air Quality Standard (NAAQS) for ozone, and neighboring Ciudad Juárez fails to meet the Mexican ambient standard for ozone. This paper summarizes the measurement campaigns of the 1996 Paso del Norte Ozone Study and the findings and conclusions that arose from subsequent data analyses. Data analyses showed that high ozone concentrations resulted from a combination of conditions, including high surface temperatures, strong sunlight with few clouds, light surface winds and high concentrations of ozone precursors at ground level in the morning, and slow convective boundary layer (CBL) growth. Synoptic-scale meteorological conditions observed during high ozone episodes included an aloft high-pressure system and aloft warming. Aloft carryover of ozone and ozone precursors did not significantly contribute to high concentrations of ozone at the surface.

  9. A Direct sensitivity approach to predict hourly ozone resulting from compliance with the National Ambient Air Quality Standard

    EPA Science Inventory

    In setting primary ambient air quality standards, the EPA’s responsibility under the law is to establish standards that protect public health. As part of the current review of the ozone National Ambient Air Quality Standard (NAAQS), the US EPA evaluated the health exposure and ...

  10. Evaluation of the Community Multiscale Air Quality Model for Simulating Winter Ozone Formation in the Uinta Basin

    EPA Science Inventory

    Areas with close proximity to oil and natural gas operations in rural Utah have experienced winter ozone levels that exceed EPA’s National Ambient Air Quality Standards (NAAQS). Through a collaborative effort, EPA Region 8 – Air Program, ORD, and OAQPS used the Commun...

  11. 77 FR 38239 - Partial Approval and Disapproval of Air Quality Implementation Plans; Arizona; Infrastructure...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-27

    ...)(1) and (2) of the Clean Air Act (CAA) for the 1997 8-hour ozone national ambient air quality standards (NAAQS) and the 1997 and 2006 NAAQS for fine particulate matter (PM 2.5 ). Section 110(a) of the... instructions for submitting comments. 2. Email: buss.jeffrey@epa.gov . 3. Fax: 415-947-3579. 4. Mail or...

  12. Fact Sheets and Additional Information Regarding the 2006 Particulate Matter (PM) National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    This page contains a fact sheet, a presentation providing an overview of the rule, and graphs and maps pertaining to the new standards that are supplementary to the October 2006 revision for the Particulate Matter (PM) NAAQS

  13. Regulatory Impact Analysis (RIA) for the Proposed Revisions to the Sulfur Dioxide National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    This Regulatory Impact Analysis (RIA) provides estimates of the incremental costs and monetized human health benefits of attaining a revised short‐term Sulfur Dioxide (SO2) NAAQS within the current monitoring network.

  14. Fact Sheets and Additional Information Regarding the 2012 Decision to Retain the Secondary NAAQS for Nitrogen Dioxide and Sulfur Dioxide

    EPA Pesticide Factsheets

    On April 3, 2012, EPA sdecided to retain the current secondary national ambient air quality standard (NAAQS) for nitrogen dioxide (NO2) and sulfur dioxide (SO2).This page contains a fact sheet describing that action.

  15. Fact Sheets and Additional information Regarding the 2012 Particulate Matter (PM) National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    Find tools for particulate matter, maps of nonattainment areas, an overview of the proposal, and information on designations, monitoring and permitting requirements and a presentation on the 2012 PM NAAQS revision.

  16. 75 FR 69036 - Notice of Data Availability Regarding Potential Changes to Required Ozone Monitoring Seasons for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-10

    ... Monitoring Seasons for Colorado, Kansas, and Utah AGENCY: Environmental Protection Agency (EPA). ACTION... monitoring seasons. The data for these states consist of daily maximum 8-hour ozone concentrations. These... could impact changes to the current and proposed required ozone monitoring seasons for Colorado,...

  17. Modeling Stomatal Conductance to Estimate Seasonal Uptake in the Ozone-Sensitive Bioindicator Plant Common Milkweed (A. syriaca L.)

    NASA Astrophysics Data System (ADS)

    Bergweiler, C.

    2008-12-01

    The US EPA National Ambient Air Quality Standard (NAAQS) was not conceived to nor does it provide an accurate definition of the absorbed ozone dose or baseline exposure level to protect vegetation. This research presents a multiplicative modeling approach based not only on atmospheric, but on equally important physiological, phenological, and environmental parameters. Physiological constraints on ozone uptake demonstrate that actual absorption is substantially lower than that assumed by a simple interpretation of hourly atmospheric ozone concentrations. Coupled with development of foliar injury expression this provides evidence that tropospheric ozone is more toxic to vegetation than is currently understood.

  18. Ozone emissions from a "personal air purifier".

    PubMed

    Phillips, T J; Bloudoff, D P; Jenkins, P L; Stroud, K R

    1999-01-01

    Ozone emissions were measured above a "personal air purifier" (PAP) designed to be worn on a lapel, shirt pocket, or neck strap. The device is being marketed as a negative ion generator that purifies the air. However, it also produces ozone within the person's immediate breathing zone. In order to assess worst-case potential human exposure to ozone at the mouth and nose, we measured ozone concentrations in separate tests at 1, 3, 5, and 6 in. above each of two PAPs in a closed office. One PAP was new, and one had been used slightly for 3 months. Temperature, relative humidity, atmospheric pressure, room ozone concentration, and outdoor ozone concentration also were measured concurrently during the tests. Average ozone levels measured directly above the individual PAPs ranged from 65-71 ppb at 6 in. above the device to 268-389 ppb at 1 in. above the device. Ozone emission rates from the PAPs were estimated to be 1.7-1.9 microg/minute. When house dust was sprinkled on the top grid of the PAPs, one showed an initial peak of 522 ppb ozone at 1 in., and then returned to the 200-400 ppb range. Room ozone levels increased by only 0-5 ppb during the tests. Even when two PAPs were left operating over a weekend, room ozone levels did not noticeably increase beyond background room ozone levels. These results indicate that this "PAP," even without significant background ozone, can potentially elevate the user's exposures to ozone levels greater than the health-based air quality standards for outdoor air in California (0.09 ppm, 1-hour average) and the United States (0.08 ppm, 8-hour average).

  19. Ozone production during an urban air stagnation episode over Nashville, Tennessee

    NASA Astrophysics Data System (ADS)

    Valente, R. J.; Imhoff, R. E.; Tanner, R. L.; Meagher, J. F.; Daum, P. H.; Hardesty, R. M.; Banta, R. M.; Alvarez, R. J.; McNider, R. T.; Gillani, N. V.

    1998-09-01

    The highest O3 levels observed during the 1995 Southern Oxidants Study in middle Tennessee occurred during a period of air stagnation from July 11 through July 15. Extensive airborne (two fixed wing and one helicopter) and ground-based measurements of the chemistry and meteorology of this episode near Nashville, Tennessee, are presented. In situ airborne measurements include O3, NOy, NO, NO2, SO2, CO, nitrate, hydrocarbons, and aldehydes. Airborne LIDAR O3 measurements are also utilized to map the vertical and horizontal extent of the urban plume. The use of multiple instrumented research aircraft permitted highly detailed mapping of the plume chemistry in the vertical and horizontal dimensions. Interactions between the urban Nashville plume (primarily a NOx and hydrocarbon source) and the Gallatin coal-fired power plant plume (primarily a NOx and SO2 source) are also documented, and comparisons of ozone formation in the isolated and mixed urban and power plant plume are presented. The data suggest that during this episode the background air and the edges of the urban plume are NOx sensitive and the core of the urban plume is hydrocarbon sensitive. Under these worst case meteorological conditions, ambient O3 levels well over the level of the new National Ambient Air Quality Standard (NAAQS) for ozone (80 ppb) were observed over and just downwind of Nashville. For example, on July 12, the boundary layer air upwind of Nashville showed 60 to 70 ppb O3, while just downwind of the city the urban plume maximum was over 140 ppb O3. With a revised ozone standard set at 80 ppb (8 hour average) and upwind levels already within 10 or 20 ppb of the standard, only a slight increase in ozone from the urban area will cause difficulty in attaining the standard at monitors near the core of the urban plume during this type of episode. The helicopter mapping and LIDAR aircraft data clearly illustrate that high O3 levels can occur during stagnation episodes within a few kilometers of

  20. Evaluation of Retinal Nerve Fiber Layer Thickness and Axonal Transport 1 and 2 Weeks After 8 Hours of Acute Intraocular Pressure Elevation in Rats

    PubMed Central

    Abbott, Carla J.; Choe, Tiffany E.; Lusardi, Theresa A.; Burgoyne, Claude F.; Wang, Lin; Fortune, Brad

    2014-01-01

    Purpose. To compare in vivo retinal nerve fiber layer thickness (RNFLT) and axonal transport at 1 and 2 weeks after an 8-hour acute IOP elevation in rats. Methods. Forty-seven adult male Brown Norway rats were used. Procedures were performed under anesthesia. The IOP was manometrically elevated to 50 mm Hg or held at 15 mm Hg (sham) for 8 hours unilaterally. The RNFLT was measured by spectral-domain optical coherence tomography. Anterograde and retrograde axonal transport was assessed from confocal scanning laser ophthalmoscopy imaging 24 hours after bilateral injections of 2 μL 1% cholera toxin B-subunit conjugated to AlexaFluor 488 into the vitreous or superior colliculi, respectively. Retinal ganglion cell (RGC) and microglial densities were determined using antibodies against Brn3a and Iba-1. Results. The RNFLT in experimental eyes increased from baseline by 11% at 1 day (P < 0.001), peaked at 19% at 1 week (P < 0.0001), remained 11% thicker at 2 weeks (P < 0.001), recovered at 3 weeks (P > 0.05), and showed no sign of thinning at 6 weeks (P > 0.05). There was no disruption of anterograde transport at 1 week (superior colliculi fluorescence intensity, 75.3 ± 7.9 arbitrary units [AU] for the experimental eyes and 77.1 ± 6.7 AU for the control eyes) (P = 0.438) or 2 weeks (P = 0.188). There was no obstruction of retrograde transport at 1 week (RCG density, 1651 ± 153 per mm2 for the experimental eyes and 1615 ± 135 per mm2 for the control eyes) (P = 0.63) or 2 weeks (P = 0.25). There was no loss of Brn3a-positive RGC density at 6 weeks (P = 0.74) and no increase in microglial density (P = 0.92). Conclusions. Acute IOP elevation to 50 mm Hg for 8 hours does not cause a persisting axonal transport deficit at 1 or 2 weeks or a detectable RNFLT or RGC loss by 6 weeks but does lead to transient RNFL thickening that resolves by 3 weeks. PMID:24398096

  1. Ozone trends in Atlanta, Georgia - Have emission controls been effective?

    NASA Technical Reports Server (NTRS)

    Lindsay, Ronald W.; Richardson, Jennifer L.; Chameldes, William L.

    1989-01-01

    Nine years of summertime ozone data from the Atlanta metropolitan area are analyzed and compared to local emissions of volatile organic carbon and nitrogen oxides. Trends from 1979 to 1987 were studied for the number of days per year ozone exceeded the NAAQS standard, the second-highest ozone level observed per year, and the first quartile summertime average ozone observed, as well as the mean difference between the ozone level observed downwind and upwind of the city. Because this last parameter is sensitive to chemical factors but relatively insensitive to the number of days each year with meteorological conditions conducive to ozone formation, its trend may be best suited for determining how effective emission controls have been in reducing O3 in the Atlanta area. In spite of the fact that sizeable reductions have been claimed for volatile organic carbon emissions over the past several years, the data give no indication that ozone levels have decreased and in fact, imply that summertime ozone production may have increased. The results imply that either emissions have not decreased as much as has been claimed or that ozone is not sensitive to anthropogenic volatile organic carbon emissions.

  2. Estimating the Influence of Oil and Gas Emissions on Urban Ozone and Associated Health Risks

    NASA Astrophysics Data System (ADS)

    Capps, S.; Nsanzineza, R.; Turner, M. D.; Henze, D. K.; Zhao, S.; Russell, M. G.; Hakami, A.; Milford, J. B.

    2015-12-01

    Tropospheric ozone (O3) degrades air quality, impacting human health and public welfare. The National Ambient Air Quality Standard (NAAQS) is designed to limit these impacts, but certain areas in the continental U.S. exceed this standard. Mitigating O3 NAAQS exceedances by designing emissions controls can be complicated in urban areas because of the long-range transport of ozone and its gaseous precursors as well as the complex mix of local emissions sources. Recent growth of unconventional oil and gas development near urban areas in Colorado, Texas, and the northeastern corridor has exacerbated this problem. To estimate the contribution of emissions from oil and gas development to urban O3 issues, we apply the CMAQ adjoint, which efficiently elucidates the relative influence of emissions sources on select concentration-based metrics. Specifically, the adjoint is used to calculate the spatially-specific relative contributions of emissions of oxides of nitrogen (NOx) and volatile organic compounds (VOCs) throughout the continental U.S. to O3 NAAQS exceedances and to ozone-related health risks in select urban areas. By evaluating these influences for different urban areas, including one in California that has been managing air quality with adjacent oil and gas development for a longer period of time, we are able to compare and contrast the emissions control strategies that may be more effective in particular regions. Additionally, the resulting relationships between emissions and concentrations provide a way to project ozone impacts when measurements provide refined estimates of emissions from this sector.

  3. EPA Proposes to Move DFW Area into Severe Ozone Category

    EPA Pesticide Factsheets

    DALLAS - (Feb. 10, 2015) The U.S. Environmental Protection Agency (EPA) proposed to reclassify the Dallas-Fort Worth area (DFW) as being in severe nonattainment of the original 8-hour ozone standard of 84 parts per billion. The proposal will be publ

  4. Health Benefits from Large-Scale Ozone Reduction in the United States

    PubMed Central

    Berman, Jesse D.; Fann, Neal; Hollingsworth, John W.; Pinkerton, Kent E.; Rom, William N.; Szema, Anthony M.; Breysse, Patrick N.; White, Ronald H.

    2012-01-01

    Background: Exposure to ozone has been associated with adverse health effects, including premature mortality and cardiopulmonary and respiratory morbidity. In 2008, the U.S. Environmental Protection Agency (EPA) lowered the primary (health-based) National Ambient Air Quality Standard (NAAQS) for ozone to 75 ppb, expressed as the fourth-highest daily maximum 8-hr average over a 24-hr period. Based on recent monitoring data, U.S. ozone levels still exceed this standard in numerous locations, resulting in avoidable adverse health consequences. Objectives: We sought to quantify the potential human health benefits from achieving the current primary NAAQS standard of 75 ppb and two alternative standard levels, 70 and 60 ppb, which represent the range recommended by the U.S. EPA Clean Air Scientific Advisory Committee (CASAC). Methods: We applied health impact assessment methodology to estimate numbers of deaths and other adverse health outcomes that would have been avoided during 2005, 2006, and 2007 if the current (or lower) NAAQS ozone standards had been met. Estimated reductions in ozone concentrations were interpolated according to geographic area and year, and concentration–response functions were obtained or derived from the epidemiological literature. Results: We estimated that annual numbers of avoided ozone-related premature deaths would have ranged from 1,410 to 2,480 at 75 ppb to 2,450 to 4,130 at 70 ppb, and 5,210 to 7,990 at 60 ppb. Acute respiratory symptoms would have been reduced by 3 million cases and school-loss days by 1 million cases annually if the current 75-ppb standard had been attained. Substantially greater health benefits would have resulted if the CASAC-recommended range of standards (70–60 ppb) had been met. Conclusions: Attaining a more stringent primary ozone standard would significantly reduce ozone-related premature mortality and morbidity. PMID:22809899

  5. Influence of Emissions from Oil and Gas Development on Elevated Ozone in the Northern Colorado Front Range

    NASA Astrophysics Data System (ADS)

    Evans, J. M.; Helmig, D.; Thompson, C. R.

    2014-12-01

    The Northern Colorado Front Range (NCFR) region has been in exceedance of the ozone National Ambient Air Quality Standard (NAAQS) since 2004. Rapidly growing oil and natural gas (O&NG) operations in the Denver-Julesberg Basin, NNE of the Denver metropolitan area, continue to be one of the largest volatile organic compound emitting sources in the region. Trend analysis of the last 13 years of Denver/NCFR ozone monitoring from five sites does not show any statistically significant decrease in annual regulated ozone maxima despite state efforts to mitigate ozone precursor emissions. In this work, we investigate the contribution of O&NG emissions to continued exceedances of the ozone NAAQS. We use surface ozone and wind data from two sites near Boulder, Colorado, to investigate the climatology of ozone in the NCFR region. Transport analyses show a preponderance of elevated ozone events associated with transport from the O&NG operations area in the N-ESE sector, rather than from the more densely populated Denver metro area to the SE-S. On average, between the two sites, air transport from areas associated with dense O&NG operations accounts for 65% of 1-hr averaged elevated ozone (>75 ppbv), while transport from the densely populated Denver metropolitan area accounts for only 9%.

  6. NAAQS (National Ambient Air Quality Standards) exposure model (NEM) applied to carbon monoxide: addendum. Final report

    SciTech Connect

    Paul, R.A.; Johnson, T.

    1985-04-01

    The report describes the results obtained when the carbon monoxide (CO) version of NEM is used to estimate national exposures associated with attaining the current CO standard (9 ppm, one observed exceedance). This standard was not analyzed in the basic report of the same title (EPA-450/5-83-003). NEM is a simulation model that simulates the intersection of a population with pollutant concentrations over space and time to estimate exposures that would obtain if various alternative NAAQs were just met. Estimates are presented for adults with cardiovascular disease in four urban study areas and for a nationwide extrapolation.

  7. 40 CFR 51.902 - Which classification and nonattainment area planning provisions of the CAA shall apply to areas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... area planning provisions of the CAA shall apply to areas designated nonattainment for the 1997 8-hour NAAQS? 51.902 Section 51.902 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Implementation of 8-hour Ozone National Ambient Air Quality Standard § 51.902 Which classification...

  8. Lower Boundary Layer and Ozone Profiles Over Fresno during Wildfire Events

    NASA Astrophysics Data System (ADS)

    Ogunjemiyo, S. O.; Omolayo, S. A.

    2010-12-01

    Ozone is a secondary pollutant in the troposphere that is largely formed as a result of photolytic reactions related to ozone precursors such as methane (CH4), carbon monoxide (CO), nitrogen oxides (NOx) and VOCs (Volatile Organic Compounds like isoprene, benzene etc.). Hence, processes and factors regulating emissions of ozone precursors are important in controlling spatial and temporal variation of ozone concentrations. Giving favorable meteorological conditions, large scale wildfires in fuel rich areas have been recognized for their potential to significantly affect the regional and global distributions of tropospheric O3, and also increases the background surface ozone concentrations above the NAAQS level, even in areas that may be hundreds of miles away from wildfire locations. Improving regional ozone forecast thus requires not only the knowledge of the amount of ozone precursors released into the atmosphere and ozone produced during wildfires, but also information on boundary layer dynamics and vertical ozone transport. In this study effort is made to characterize ozone transport in the lower urban boundary layer during wildfire events. In this regard, tethersonde and ozonesonde measurements were made over Fresno California in the period the region was affected by smoke particles from the Moonlight fire in September 2007 and the Telegraph fire in July 2008. Analysis of the profiles data showed that the Fresno Eddy, in addition to boundary layer dynamics, particularly the down mixing of high ozone concentration in the residual boundary layer, were significant factors influencing hourly measured ground level ozone concentration at the site.

  9. Spatio-temporal modeling for real-time ozone forecasting.

    PubMed

    Paci, Lucia; Gelfand, Alan E; Holland, David M

    2013-05-01

    The accurate assessment of exposure to ambient ozone concentrations is important for informing the public and pollution monitoring agencies about ozone levels that may lead to adverse health effects. High-resolution air quality information can offer significant health benefits by leading to improved environmental decisions. A practical challenge facing the U.S. Environmental Protection Agency (USEPA) is to provide real-time forecasting of current 8-hour average ozone exposure over the entire conterminous United States. Such real-time forecasting is now provided as spatial forecast maps of current 8-hour average ozone defined as the average of the previous four hours, current hour, and predictions for the next three hours. Current 8-hour average patterns are updated hourly throughout the day on the EPA-AIRNow web site. The contribution here is to show how we can substantially improve upon current real-time forecasting systems. To enable such forecasting, we introduce a downscaler fusion model based on first differences of real-time monitoring data and numerical model output. The model has a flexible coefficient structure and uses an efficient computational strategy to fit model parameters. Our hybrid computational strategy blends continuous background updated model fitting with real-time predictions. Model validation analyses show that we are achieving very accurate and precise ozone forecasts.

  10. Alteration in carboxyhemoglobin concentrations during exposure to 9 ppm carbon monoxide for 8 hours at sea level and 2134 m altitude in a hypobaric chamber

    SciTech Connect

    Horvath, S.M.; Bedi, J.F. )

    1989-10-01

    Seventeen non-smoking young men served as subjects to determine the alteration in carboxyhemoglobin (COHb) concentrations during exposure to 0 or 9 ppm carbon monoxide for 8 hours (CO) at sea level or an altitude of 2134 meters (7000 feet) in a hypobaric chamber. Nine subjects rested during the exposure and 8 exercised for 10 minutes of each exposure hour at a mean ventilation of 25 L (BTPS). All subjects performed a maximal aerobic capacity test at the completion of their respective exposures. Carboxyhemoglobin concentrations fell in all subjects during their exposures to 0 ppm CO at sea level or 2134 m. During the 8-h exposures to 9 ppm CO, COHb rose linearly from approximately 0.2 percent to 0.7 percent. No significant differences in uptake were found whether the subjects were resting or intermittently exercising during their 8-h exposures. COHb levels attained were similar at both sea level and 2134 m. Maximal aerobic capacity was reduced approximately 7-10 percent consequent to altitude exposure during 0 ppm CO exposures. These values were not altered following exposure for 8 h to 9 ppm CO in either the resting or exercising subjects.

  11. The Use of Regulatory Air Quality Models to Develop Successful Ozone Attainment Strategies

    NASA Astrophysics Data System (ADS)

    Canty, T. P.; Salawitch, R. J.; Dickerson, R. R.; Ring, A.; Goldberg, D. L.; He, H.; Anderson, D. C.; Vinciguerra, T.

    2015-12-01

    The Environmental Protection Agency (EPA) recently proposed lowering the 8-hr ozone standard to between 65-70 ppb. Not all regions of the U.S. are in attainment of the current 75 ppb standard and it is expected that many regions currently in attainment will not meet the future, lower surface ozone standard. Ozone production is a nonlinear function of emissions, biological processes, and weather. Federal and state agencies rely on regulatory air quality models such as the Community Multi-Scale Air Quality (CMAQ) model and Comprehensive Air Quality Model with Extensions (CAMx) to test ozone precursor emission reduction strategies that will bring states into compliance with the National Ambient Air Quality Standards (NAAQS). We will describe various model scenarios that simulate how future limits on emission of ozone precursors (i.e. NOx and VOCs) from sources such as power plants and vehicles will affect air quality. These scenarios are currently being developed by states required to submit a State Implementation Plan to the EPA. Projections from these future case scenarios suggest that strategies intended to control local ozone may also bring upwind states into attainment of the new NAAQS. Ground based, aircraft, and satellite observations are used to ensure that air quality models accurately represent photochemical processes within the troposphere. We will highlight some of the improvements made to the CMAQ and CAMx model framework based on our analysis of NASA observations obtained by the OMI instrument on the Aura satellite and by the DISCOVER-AQ field campaign.

  12. Projecting policy-relevant metrics to characterize changing ozone extremes over the US: Variations by region, season and scenario

    NASA Astrophysics Data System (ADS)

    Rieder, Harald E.; Fiore, Arlene M.; Correa, Gus; Clifton, Olivia; Horrowitz, Larry W.; Naik, Vaishali

    2015-04-01

    Nitrogen oxide (NOx) emission controls have led to improved air quality (particularly in the Eastern US) over the past two decades, but concerns have been raised that climate warming may offset some of these gains in the coming decades. Here we address these concerns by analyzing the effect of projected future changes of emissions and climate, in isolation and combination, on US surface ozone (O3) during the 21st century in an ensemble of simulations (3 members per scenario) performed with the GFDL chemistry-climate model CM3. We analyze two Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5. Under both scenarios, NOx emissions decrease by ~80% over North America by 2100. In additional 3-member ensemble simulations, termed RCP4.5_WMGG and RCP8.5_WMGG, well-mixed greenhouse gases follow the respective RCP but O3 and aerosol precursor emissions are held at 2005 levels. These simulations enable us to isolate the role of well-mixed greenhouse gas induced climate change from that of emission reductions. Another set of simulations, following RCP8.5 but with methane (CH4) held fixed at 2005 levels, termed RCP8.5_2005CH4, allows us to quantify the background influence of CH4 on O3. For each season, we examine changes in the surface O3 distribution over the US during the 21st century, calculating policy relevant statistics: days above the current national ambient air quality standard (NAAQS) of 75 ppb and other proposed future levels, as well as the probabilistic 1-year return levels for maximum daily 8-hour average ozone (MDA8 O3), within each model grid cell. Specifically, we analyze: (i) regional and seasonal changes in the frequency and return level of high O3 pollution events during the 21st century, as well as (ii) differences among the RCPs by the middle and end of the 21st century. We find that the response of surface O3 to changes in emissions and climate varies strongly, seasonally and spatially, with certain regions more prone to a 'climate

  13. Projecting Policy-Relevant Metrics to Characterize Changing Ozone Extremes over the US: Variations by Region, Season and Scenario

    NASA Astrophysics Data System (ADS)

    Rieder, H. E.; Fiore, A. M.; Correa, G. J. P.; Clifton, O.; Horowitz, L. W.; Naik, V.

    2014-12-01

    Nitrogen oxide (NOx) emission controls have led to improved air quality (particularly in the Eastern US) over the past two decades, but concerns have been raised that climate warming may offset some of these gains in the coming decades. Here we address these concerns by analyzing the effect of projected future changes of emissions and climate, in isolation and combination, on US surface ozone (O3) during the 21st century in an ensemble of simulations (3 members per scenario) performed with the GFDL chemistry-climate model CM3. We analyze two Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5. Under both scenarios, NOx emissions decrease by ~80% over North America by 2100. In additional 3-member ensemble simulations, termed RCP4.5_WMGG and RCP8.5_WMGG, well-mixed greenhouse gases follow the respective RCP but O3 and aerosol precursor emissions are held at 2005 levels. These simulations enable us to isolate the role of well-mixed greenhouse gas induced climate change from that of emission reductions. Another set of simulations, following RCP8.5 but with methane (CH4) held fixed at 2005 levels, termed RCP8.5_2005CH4, allows us to quantify the background influence of CH4 on O3. For each season, we examine changes in the surface O3 distribution over the US during the 21st century, calculating policy relevant statistics: days above the current national ambient air quality standard (NAAQS) of 75 ppb and other proposed future levels, as well as the probabilistic 1-year return levels for maximum daily 8-hour average ozone (MDA8 O3), within each model grid cell. Specifically, we analyze: (i) regional and seasonal changes in the frequency and return level of high O3 pollution events during the 21st century, as well as (ii) differences among the RCPs by the middle and end of the 21st century. We find that the response of surface O3 to changes in emissions and climate varies strongly, seasonally and spatially, with certain regions more prone to a 'climate

  14. Ozone Basics

    EPA Pesticide Factsheets

    Learn the difference between good (stratospheric) and bad (tropospheric) ozone, how bad ozone affects our air quality, health, and environment, and what EPA is doing about it through regulations and standards.

  15. 75 FR 76332 - Approval and Promulgation of Air Quality Implementation Plans; Illinois

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Illinois AGENCY...) for purposes of attaining the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS). The... emissions depend on the ozone nonattainment classification of an area. The air quality planning and...

  16. 76 FR 43637 - Approval and Promulgation of Air Quality Plans: State of Missouri

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-21

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Plans: State of Missouri AGENCY... ozone National Ambient Air Quality Standard (NAAQS). The Missouri NO X RACT waiver request for its... portion of the St. Louis (MO-IL) metropolitan 8-hour ozone nonattainment area from the Clean Air Act...

  17. 77 FR 71551 - Approval and Promulgation of Implementation Plans; California; Determinations of Attainment for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-03

    ... NAAQ, the basis for the suspension of the requirements for that area, provided by 40 CFR 51.918, would... for that area, provided by 40 CFR 51.918, would no longer exist, and the violating ozone nonattainment... areas in California. First, EPA is determining that six 8-hour ozone nonattainment areas in...

  18. 77 FR 70376 - Withdrawal of Approval of Air Quality Implementation Plans and Findings of Failure To Submit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-26

    ... To Submit Required Plans; California; San Joaquin Valley; 1-Hour and 8-Hour Ozone Extreme Area Plan... California to provide for attainment of the 1-hour ozone National Ambient Air Quality Standards (NAAQS) in..., 2012 determination that the California SIP satisfies the requirement regarding offsetting...

  19. 76 FR 79579 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-22

    ... 13564). See also 40 CFR 51.918. In addition, because the St. Louis area has attained the ozone NAAQS and... AGENCY 40 CFR Parts 52 and 81 Approval and Promulgation of Implementation Plans and Designation of Areas..., MO-IL Area to Attainment for the 1997 8-Hour Ozone Standard AGENCY: Environmental Protection...

  20. 40 CFR 52.1472 - Approval status.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for the ozone portion of the State Implementation Plan (SIP) depends on the adoption and submittal by... for O3. (2) Las Vegas Valley for O3. (d) 1997 8-hour ozone NAAQS: The SIPs submitted on February 1... of the Nevada SIP; and for CAA element 110(a)(2)(F) for the Clark County portion of the Nevada...

  1. 40 CFR 52.1472 - Approval status.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for the ozone portion of the State Implementation Plan (SIP) depends on the adoption and submittal by... for O3. (2) Las Vegas Valley for O3. (d) 1997 8-hour ozone NAAQS: The SIPs submitted on February 1... of the Nevada SIP; and for CAA element 110(a)(2)(F) for the Clark County portion of the Nevada...

  2. 77 FR 75862 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-26

    ... Carolina that is within the bi-state Charlotte-Gastonia-Rock Hill, North Carolina-South Carolina ozone nonattainment area (hereafter referred to as the ``bi- state Charlotte Area,'' or ``Area'') to attainment for the 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS). The bi-state Charlotte...

  3. 77 FR 6743 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-09

    ... for Air Quality Planning Purposes; Illinois; Ozone AGENCY: Environmental Protection Agency (EPA... Greater Chicago area) to attainment of the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS... statute. Certain other material, such as copyrighted material, will be publicly available only in...

  4. Ozone Implementation Regulatory Actions

    EPA Pesticide Factsheets

    Training courses, presentations, and other resources to help state and local air professionals learn more about NAAQS implementation, air pollution control and emissions reduction, SIP development, and public participation.

  5. Carbon monoxide analysis of future attainment of the NAAQS (National Ambient Air Quality Standard) in Wichita, Kansas

    NASA Astrophysics Data System (ADS)

    Schewe, G. J.

    1985-06-01

    In order to comply with the NAAQS for CO in Wichita, Kansas, a special study was performed to demonstrate that CO concentrations at a special purpose monitor (SPM) located near Douglas and Main Streets would give results less than the NAAQS by 1987. The SPM site is located near the urban core in an area characterized by high nighttime traffic volumes and congested traffic flow. A dispersion modeling analysis was performed using the CALINE-3 Model for dispersion, the MOBILE-3 Model for vehicle emissions and local or national traffic and ambient conditions. Results of modeling the SPM site for baseline (1983) emissions were calibrated with maximum measured CO concentrations. Several scenarios were analyzed in this analysis including with and without the inspection/maintenance program and with and without the left-turn ban from Douglas to Main Streets.

  6. Fact Sheets and Additional Information Regarding the 2010 Revision to the Primary National Ambient Air Quality Standards (NAAQS) for Nitrogen Dioxide (NO2)

    EPA Pesticide Factsheets

    Find tools for primary standards for Nitrogen Dioxide, maps of monitoring areas, an overview of the proposal, monitor requirements, design values for counties, and a presentation on the 2010 NO2 primary NAAQS revision.

  7. Fact Sheets and Additional Information Regarding the 2010 Revision to the Primary National Ambient Air Quality Standards (NAAQS) for Sulfur Dioxide

    EPA Pesticide Factsheets

    Find tools for primary standards for Sulfur Dioxide, maps of nonattainment areas, an overview of the proposal, projected nonattainment areas for 2020, and a presentation on the 2011 SO2 primary NAAQS revision.

  8. Microporous carbon filters as catalysts for ozone decomposition

    SciTech Connect

    Whinnery, L.; Coutts, D.; Adams, R.; Shen, C.; Quintana, C.; Showalter, S.

    1995-02-01

    Ozone, an allotrope of oxygen, present in the upper atmosphere (ozonosphere) plays a critical role in radiative balance. However, ozone is a toxic gas with a pungent odor when present in the troposphere and is considered a health hazard. The Occupational Safety and Health Administration (OSHA) has established a maximum permissible exposure limit (PEL) of 0.1 ppM in an 8 hour period. There are many sources of exposure to ozone in the workplace. Ozone is generated by high voltage discharge wires found in laser printers and photocopiers. Other common uses for ozone include waste water treatment, medical and dental instrument sterilization, drinking water purification, industrial oxidation processes, bleaching, and as a bactericide in swimming pools. Carbon filters are often used to minimize worker exposure to ozone. When designing a filter to decompose unwanted ozone, there are three requirements for most commercial applications. The first requirement is that production costs of the filter be minimal. Many applications require large quantities of filters and may have to be changed out often. The relatively low PEL also requires the filters to have a very high ozone decomposition efficiency. Finally, current applications tend to use small, low power fans to move air through the filters. Low back pressure is required to prevent over heating and prevent buildup of the toxic and potentially explosive ozone. In this paper, we will discuss two porous carbon filters that satisfy all of these requirements.

  9. Ozone exposure and systemic biomarkers: Evaluation of evidence for adverse cardiovascular health impacts.

    PubMed

    Goodman, Julie E; Prueitt, Robyn L; Sax, Sonja N; Pizzurro, Daniella M; Lynch, Heather N; Zu, Ke; Venditti, Ferdinand J

    2015-05-01

    The US Environmental Protection Agency (EPA) recently concluded that there is likely to be a causal relationship between short-term (< 30 days) ozone exposure and cardiovascular (CV) effects; however, biological mechanisms to link transient effects with chronic cardiovascular disease (CVD) have not been established. Some studies assessed changes in circulating levels of biomarkers associated with inflammation, oxidative stress, coagulation, vasoreactivity, lipidology, and glucose metabolism after ozone exposure to elucidate a biological mechanism. We conducted a weight-of-evidence (WoE) analysis to determine if there is evidence supporting an association between changes in these biomarkers and short-term ozone exposure that would indicate a biological mechanism for CVD below the ozone National Ambient Air Quality Standard (NAAQS) of 75 parts per billion (ppb). Epidemiology findings were mixed for all biomarker categories, with only a few studies reporting statistically significant changes and with no consistency in the direction of the reported effects. Controlled human exposure studies of 2 to 5 hours conducted at ozone concentrations above 75 ppb reported small elevations in biomarkers for inflammation and oxidative stress that were of uncertain clinical relevance. Experimental animal studies reported more consistent results among certain biomarkers, although these were also conducted at ozone exposures well above 75 ppb and provided limited information on ozone exposure-response relationships. Overall, the current WoE does not provide a convincing case for a causal relationship between short-term ozone exposure below the NAAQS and adverse changes in levels of biomarkers within and across categories, but, because of study limitations, they cannot not provide definitive evidence of a lack of causation.

  10. Improved Space-Time Forecasting of next Day Ozone Concentrations in the Eastern U.S.

    EPA Science Inventory

    There is an urgent need to provide accurate air quality information and forecasts to the general public and environmental health decision-makers. This paper develops a hierarchical space-time model for daily 8-hour maximum ozone concentration (O3) data covering much of the easter...

  11. Ozone Layer Protection

    MedlinePlus

    ... EPA United States Environmental Protection Agency Search Search Ozone Layer Protection Share Facebook Twitter Google+ Pinterest Contact Us Ozone Layer Protection Welcome to EPA's ozone layer protection web ...

  12. Ozone decomposition.

    PubMed

    Batakliev, Todor; Georgiev, Vladimir; Anachkov, Metody; Rakovsky, Slavcho; Zaikov, Gennadi E

    2014-06-01

    Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers). Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates.

  13. Ozone decomposition

    PubMed Central

    Batakliev, Todor; Georgiev, Vladimir; Anachkov, Metody; Rakovsky, Slavcho

    2014-01-01

    Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers). Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates. PMID:26109880

  14. Polar ozone

    NASA Technical Reports Server (NTRS)

    Solomon, S.; Grose, W. L.; Jones, R. L.; Mccormick, M. P.; Molina, Mario J.; Oneill, A.; Poole, L. R.; Shine, K. P.; Plumb, R. A.; Pope, V.

    1990-01-01

    The observation and interpretation of a large, unexpected ozone depletion over Antarctica has changed the international scientific view of stratospheric chemistry. The observations which show the veracity, seasonal nature, and vertical structure of the Antarctic ozone hole are presented. Evidence for Arctic and midlatitude ozone loss is also discussed. The chemical theory for Antarctic ozone depletion centers around the occurrence of polar stratospheric clouds (PSCs) in Antarctic winter and spring; the climatology and radiative properties of these clouds are presented. Lab studies of the physical properties of PSCs and the chemical processes that subsequently influence ozone depletion are discussed. Observations and interpretation of the chemical composition of the Antarctic stratosphere are described. It is shown that the observed, greatly enhanced abundances of chlorine monoxide in the lower stratosphere are sufficient to explain much if not all of the ozone decrease. The dynamic meteorology of both polar regions is given, interannual and interhemispheric variations in dynamical processes are outlined, and their likely roles in ozone loss are discussed.

  15. Establishing policy relevant background (PRB) ozone concentrations in the United States.

    PubMed

    McDonald-Buller, Elena C; Allen, David T; Brown, Nancy; Jacob, Daniel J; Jaffe, Daniel; Kolb, Charles E; Lefohn, Allen S; Oltmans, Samuel; Parrish, David D; Yarwood, Greg; Zhang, Lin

    2011-11-15

    Policy Relevant Background (PRB) ozone concentrations are defined by the United States (U.S.) Environmental Protection Agency (EPA) as those concentrations that would occur in the U.S. in the absence of anthropogenic emissions in continental North America (i.e., the U.S, Canada, and Mexico). Estimates of PRB ozone have had an important role historically in the EPA's human health and welfare risk analyses used in establishing National Ambient Air Quality Standards (NAAQS). The margin of safety for the protection of public health in the ozone rulemaking process has been established from human health risks calculated based on PRB ozone estimates. Sensitivity analyses conducted by the EPA have illustrated that changing estimates of PRB ozone concentrations have a progressively greater impact on estimates of mortality risk as more stringent standards are considered. As defined by the EPA, PRB ozone is a model construct, but it is informed by measurements at relatively remote monitoring sites (RRMS). This review examines the current understanding of PRB ozone, based on both model predictions and measurements at RRMS, and provides recommendations for improving the definition and determination of PRB ozone.

  16. Ozone Pollution

    EPA Pesticide Factsheets

    Known as tropospheric or ground-level ozone, this gas is harmful to human heath and the environment. Since it forms from emissions of volatile organic compounds (VOCs) and nitrogen oxides (NOx), these pollutants are regulated under air quality standards.

  17. Ozone, Tropospheric

    NASA Technical Reports Server (NTRS)

    Fishman, Jack

    1995-01-01

    In the early part of the 20th century, ground-based and balloon-borne measurements discovered that most of atmosphere's ozone is located in the stratosphere with highest concentrations located between 15 and 30 km (9,3 and 18.6 miles). For a long time, it was believed that tropospheric ozone originated from the stratosphere and that most of it was destroyed by contact with the earth's surface. Ozone, O3, was known to be produced by the photo-dissociation of molecular oxygen, O2, a process that can only occur at wavelengths shorter than 242 nm. Because such short-wave-length radiation is present only in the stratosphere, no tropospheric ozone production is possible by this mechanism. In the 1940s, however, it became obvious that production of ozone was also taking place in the troposphere. The overall reaction mechanism was eventually identified by Arie Haagen-Smit of the California Institute of Technology, in highly polluted southern California. The copious emissions from the numerous cars driven there as a result of the mass migration to Los Angeles after World War 2 created the new unpleasant phenomenon of photochemical smog, the primary component of which is ozone. These high levels of ozone were injuring vegetable crops, causing women's nylons to run, and generating increasing respiratory and eye-irritation problems for the populace. Our knowledge of tropospheric ozone increased dramatically in the early 1950s as monitoring stations and search centers were established throughout southern California to see what could be done to combat this threat to human health and the environment.

  18. Stratospheric contribution to surface ozone in the desert Southwest during the 2013 Las Vegas Ozone Study

    NASA Astrophysics Data System (ADS)

    Langford, A. O.; Senff, C. J.; Alvarez, R. J. _II, II; Brioude, J. F.; Cooper, O. R.; Holloway, J. S.; Lin, M.; Marchbanks, R.; Pierce, R. B.; Reddy, P. J.; Sandberg, S.; Weickmann, A. M.; Williams, E. J.; Gustin, M. S.; Iraci, L. T.; Leblanc, T.; Yates, E. L.

    2014-12-01

    The 2013 Las Vegas Ozone Study (LVOS) was designed to investigate the potential impact of stratosphere-troposphere transport (STT) and long-range transport of pollution from Asia on surface O3 concentrations in Clark County, NV. This measurement campaign, which took place in May and June of 2013, was conducted at Angel Peak, NV, a high elevation site about 2.8 km above mean sea level and 45 km west of Las Vegas. The study was organized around the NOAA ESRL truck-based TOPAZ scanning ozone lidar with collocated in situ sampling of O3, CO, and meteorological parameters. These measurements were supported by the NOAA/NESDIS real time modelling system (RAQMS), FLEXPART particle dispersion model, and the NOAA GFDL AM3 model. In this talk, I will describe one of several STT events that occurred during the LVOS campaign. This intrusion, which was profiled by TOPAZ on the night of May 24-25, was also sampled by the NASA Alpha Jet, the Table Mountain ozone lidar, and by an ozonesonde flying above southern California. This event also led to significant ozone increases at surface monitors operated by Clark County, the California Air Resources Board, the U.S. National Park Service, and the Nevada Rural Ozone Initiative (NRVOI), and resulted in exceedances of the 2008 75 ppbv O3 NAAQS both in Clark County and in surrounding areas of Nevada and southern California. The potential implications of this and similar events for air quality compliance in the western U.S. will be discussed.

  19. A Reduced Form Model for Ozone Based on Two Decades of ...

    EPA Pesticide Factsheets

    A Reduced Form Model (RFM) is a mathematical relationship between the inputs and outputs of an air quality model, permitting estimation of additional modeling without costly new regional-scale simulations. A 21-year Community Multiscale Air Quality (CMAQ) simulation for the continental United States provided the basis for the RFM developed in this study. Predictors included the principal component scores (PCS) of emissions and meteorological variables, while the predictand was the monthly mean of daily maximum 8-hour CMAQ ozone for the ozone season at each model grid. The PCS form an orthogonal basis for RFM inputs. A few PCS incorporate most of the variability of emissions and meteorology, thereby reducing the dimensionality of the source-receptor problem. Stochastic kriging was used to estimate the model. The RFM was used to separate the effects of emissions and meteorology on ozone concentrations. by running the RFM with emissions constant (ozone dependent on meteorology), or constant meteorology (ozone dependent on emissions). Years with ozone-conducive meteorology were identified, and meteorological variables best explaining meteorology-dependent ozone were identified. Meteorology accounted for 19% to 55% of ozone variability in the eastern US, and 39% to 92% in the western US. Temporal trends estimated for original CMAQ ozone data and emission-dependent ozone were mostly negative, but the confidence intervals for emission-dependent ozone are much

  20. Climate change impacts on projections of excess mortality at 2030 using spatially varying ozone-temperature risk surfaces.

    PubMed

    Wilson, Ander; Reich, Brian J; Nolte, Christopher G; Spero, Tanya L; Hubbell, Bryan; Rappold, Ana G

    2017-01-01

    We project the change in ozone-related mortality burden attributable to changes in climate between a historical (1995-2005) and near-future (2025-2035) time period while incorporating a non-linear and synergistic effect of ozone and temperature on mortality. We simulate air quality from climate projections varying only biogenic emissions and holding anthropogenic emissions constant, thus attributing changes in ozone only to changes in climate and independent of changes in air pollutant emissions. We estimate non-linear, spatially varying, ozone-temperature risk surfaces for 94 US urban areas using observed data. Using the risk surfaces and climate projections we estimate daily mortality attributable to ozone exceeding 40 p.p.b. (moderate level) and 75 p.p.b. (US ozone NAAQS) for each time period. The average increases in city-specific median April-October ozone and temperature between time periods are 1.02 p.p.b. and 1.94 °F; however, the results varied by region. Increases in ozone because of climate change result in an increase in ozone mortality burden. Mortality attributed to ozone exceeding 40 p.p.b. increases by 7.7% (1.6-14.2%). Mortality attributed to ozone exceeding 75 p.p.b. increases by 14.2% (1.6 28.9%). The absolute increase in excess ozone mortality is larger for changes in moderate ozone levels, reflecting the larger number of days with moderate ozone levels.

  1. 78 FR 17197 - Adequacy Status of Motor Vehicle Emissions Budgets in Submitted Ozone Maintenance Plan for San...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-20

    ... transportation activities will not produce new air quality violations, worsen existing violations, or delay... maintenance plan for the 1997 8-hour ozone national ambient air quality standard. As a result of our adequacy... conformity is required by Clean Air Act section 176(c). EPA's conformity rule requires that...

  2. Pulmonary Responses in Healthy Young Adults Exposed to Low Concentration of Ozone for 6.6 Hours with Mild Exercise

    EPA Science Inventory

    Rational: Recent studies have shown small but significant decreases in lung function following a prolonged exposure (6.6 hour) of healthy young adults to levels of ozone (0.08 ppm) near the current 8 hour standard. It is unclear, however, if such effects may be extended to concen...

  3. Evaluation of Global Model Simulation of Tropospheric Ozone from ECHAM6-HAMMOZ1 with Surface Measurements over the Mediterranean Region

    NASA Astrophysics Data System (ADS)

    Kaffashzadeh, Najmeh; Schultz, Martin G.; Lyapina, Olga; Schröder, Sabine; Stadtler, Scarlet

    2016-04-01

    Current chemistry transport models are generally successful in describing the principle features of the present-day global tropospheric ozone (O3) distribution, but they exhibit large differences of ozone concentrations over the Mediterranean region. The Mediterranean region can be perturbed by long-range pollution import from Northern Europe, North Africa and Asia, in addition to local emissions, which may all contribute to ozone concentrations in this area. Identifying the main drivers for Mediterranean ozone concentrations and understanding the reasons for the inter-model differences remain scientific challenges. To investigate the geographical distribution of tropospheric ozone over the Mediterranean, we analyze hourly surface ozone measurements from more than 1000 stations in the Tropospheric Ozone Assessment Report (TOAR) database and compare these to hourly model outputs from the global chemistry climate model ECHAM6-HAMMOZ1 for the year 2012. The daily maximum 8-hour running mean value of ozone mixing ratios is calculated for both model and observation and compared. The preliminary results show that the model captures many features of the ozone and its precursor concentrations in many regions of Europe throughout the year. However, it substantially underestimates ozone in the Po Valley region in summer and overestimates ozone over much of the Mediterranean region during spring. The reasons for this behavior will be investigated through detailed sensitivity studies with respect to VOC emissions, anthropogenic emissions, ozone deposition, specific chemical reactions, and long range-import of ozone and precursors.

  4. Regulatory ozone modeling: status, directions, and research needs.

    PubMed Central

    Georgopoulos, P G

    1995-01-01

    The Clean Air Act Amendments (CAAA) of 1990 have established selected comprehensive, three-dimensional, Photochemical Air Quality Simulation Models (PAQSMs) as the required regulatory tools for analyzing the urban and regional problem of high ambient ozone levels across the United States. These models are currently applied to study and establish strategies for meeting the National Ambient Air Quality Standard (NAAQS) for ozone in nonattainment areas; State Implementation Plans (SIPs) resulting from these efforts must be submitted to the U.S. Environmental Protection Agency (U.S. EPA) in November 1994. The following presentation provides an overview and discussion of the regulatory ozone modeling process and its implications. First, the PAQSM-based ozone attainment demonstration process is summarized in the framework of the 1994 SIPs. Then, following a brief overview of the representation of physical and chemical processes in PAQSMs, the essential attributes of standard modeling systems currently in regulatory use are presented in a nonmathematical, self-contained format, intended to provide a basic understanding of both model capabilities and limitations. The types of air quality, emission, and meteorological data needed for applying and evaluating PAQSMs are discussed, as well as the sources, availability, and limitations of existing databases. The issue of evaluating a model's performance in order to accept it as a tool for policy making is discussed, and various methodologies for implementing this objective are summarized. Selected interim results from diagnostic analyses, which are performed as a component of the regulatory ozone modeling process for the Philadelphia-New Jersey region, are also presented to provide some specific examples related to the general issues discussed in this work. Finally, research needs related to a) the evaluation and refinement of regulatory ozone modeling, b) the characterization of uncertainty in photochemical modeling, and c

  5. Synoptic and meteorological drivers of extreme ozone concentrations over Europe

    NASA Astrophysics Data System (ADS)

    Otero, Noelia Felipe; Sillmann, Jana; Schnell, Jordan L.; Rust, Henning W.; Butler, Tim

    2016-04-01

    The present work assesses the relationship between local and synoptic meteorological conditions and surface ozone concentration over Europe in spring and summer months, during the period 1998-2012 using a new interpolated data set of observed surface ozone concentrations over the European domain. Along with local meteorological conditions, the influence of large-scale atmospheric circulation on surface ozone is addressed through a set of airflow indices computed with a novel implementation of a grid-by-grid weather type classification across Europe. Drivers of surface ozone over the full distribution of maximum daily 8-hour average values are investigated, along with drivers of the extreme high percentiles and exceedances or air quality guideline thresholds. Three different regression techniques are applied: multiple linear regression to assess the drivers of maximum daily ozone, logistic regression to assess the probability of threshold exceedances and quantile regression to estimate the meteorological influence on extreme values, as represented by the 95th percentile. The relative importance of the input parameters (predictors) is assessed by a backward stepwise regression procedure that allows the identification of the most important predictors in each model. Spatial patterns of model performance exhibit distinct variations between regions. The inclusion of the ozone persistence is particularly relevant over Southern Europe. In general, the best model performance is found over Central Europe, where the maximum temperature plays an important role as a driver of maximum daily ozone as well as its extreme values, especially during warmer months.

  6. Evaluation of microporous carbon filters as catalysts for ozone decomposition

    SciTech Connect

    Whinnery, L.; Coutts, D.; Shen, C.; Adams, R.; Quintana, C.; Showalter, S.

    1994-12-31

    Ozone is produced in small quantities in photocopiers and laser printers in the workplace and large quantities in industrial waste water treatment facilities. Carbon filters are commonly used to decompose this unwanted ozone. The three most important factors in producing a filter for this purpose are flow properties, efficiency, and cost. Most ozone decomposition applications require very low back-pressure at modest flow rates. The tradeoff between the number of pores and the size of the pores will be discussed. Typical unfiltered emissions in the workplace are approximately 1 ppm. The maximum permissible exposure limit, PEL, for worker exposure to ozone is 0.1 ppm over 8 hours. Several methods have been examined to increase the efficiency of ozone decomposition. Carbon surfaces were modified with catalysts, the surface activated, and the surface area was increased, in attempts to decompose ozone more effectively. Methods to reduce both the processing and raw material costs were investigated. Several sources of microporous carbon were investigated as ozone decomposition catalysts. Cheaper processing routes including macropore templating, faster drying and extracting methods were also studied.

  7. 77 FR 24399 - Approval and Promulgation of Implementation Plans; Georgia; Atlanta; Ozone 2002 Base Year...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-24

    ... national ambient air quality standards (NAAQS). The Atlanta Area is comprised of Barrow, Bartow, Carroll... 5.69 4.30 1.41 0.75 Bartow 69.92 1.31 1.30 8.05 15.76 10.56 3.89 2.54 Carroll 0.06 0.85 1.30 9.54 10... Ozone 2002 Barrow, Bartow, Carroll, 10/21/2009 4/24/2012 [Insert Base-Year Emissions Inventory....

  8. Analysis of short-term ozone and PM2.5 measurements: Characteristics and relationships for air sensor messaging.

    PubMed

    Mannshardt, Elizabeth; Benedict, Kristen; Jenkins, Scott; Keating, Martha; Mintz, David; Stone, Susan; Wayland, Richard

    2017-04-01

    Air quality sensors are becoming increasingly available to the general public, providing individuals and communities with information on fine-scale, local air quality in increments as short as 1 min. Current health studies do not support linking 1-min exposures to adverse health effects; therefore, the potential health implications of such ambient exposures are unclear. The U.S. Environmental Protection Agency (EPA) establishes the National Ambient Air Quality Standards (NAAQS) and Air Quality Index (AQI) on the best science available, which typically uses longer averaging periods (e.g., 8 hr; 24 hr). Another consideration for interpreting sensor data is the variable relationship between pollutant concentrations measured by sensors, which are short-term (1 min to 1 hr), and the longer term averages used in the NAAQS and AQI. In addition, sensors often do not meet federal performance or quality assurance requirements, which introduces uncertainty in the accuracy and interpretation of these readings. This article describes a statistical analysis of data from regulatory monitors and new real-time technology from Village Green benches to inform the interpretation and communication of short-term air sensor data. We investigate the characteristics of this novel data set and the temporal relationships of short-term concentrations to 8-hr average (ozone) and 24-hr average (PM2.5) concentrations to examine how sensor readings may relate to the NAAQS and AQI categories, and ultimately to inform breakpoints for sensor messages. We consider the empirical distributions of the maximum 8-hr averages (ozone) and 24-hr averages (PM2.5) given the corresponding short-term concentrations, and provide a probabilistic assessment. The result is a robust, empirical comparison that includes events of interest for air quality exceedances and public health communication. Concentration breakpoints are developed for short-term sensor readings such that, to the extent possible, the related air

  9. Tropopause Ozone

    NASA Astrophysics Data System (ADS)

    Prather, M.; Zhu, X.; Hsu, J.; Neu, J.; Tang, Q.

    2009-04-01

    The tropopause, however defined, is meant to describe the boundary between the well mixed troposphere and the stably stratified stratosphere. Ozone abundances in the vicinity of the tropopause exhibit large variations with latitude and season, being controlled by a combination of large-scale transport like the Brewer-Dobson circulation, small-scale turbulent mixing unresolved by global models, and photochemistry. A clear, instantaneous, 3-D definition of the tropopause is needed for diagnostics that separate stratosphere from troposphere, e.g., strat-trop exchange fluxes. In the UCI CTM, we define the stratosphere-troposphere boundary with what is effectively an age-of-air tracer: a tracer emitted uniformly from the surface with a uniform e-fold of 90 days (designated e90). Where the abundance of e90 falls below about 70% of the mass-median value (i.e., 33 days-old), we define as the stratosphere. With this diagnostic of the mixing barrier between stratosphere and troposphere the CTM with EC IFS forecast meteorology is able to match much of the observed seasonal cycle of the tropopause pressure and ozone abundance. With the CTM we examine the importance of chemistry vs. transport in controlling tropopause ozone. For example, we note that photolysis of molecular oxygen in the upper troposphere contributes significantly to tropopause ozone in the tropics and sub-tropics.

  10. Development of a sensitive passive sampler using indigotrisulfonate for the determination of tropospheric ozone.

    PubMed

    Garcia, Gabriel; Allen, Andrew George; Cardoso, Arnaldo Alves

    2010-06-01

    A new sampling and analytical design for measurement of ambient ozone is presented. The procedure is based on ozone absorption and decoloration (at 600 nm) of indigotrisulfonate dye, where ozone adds itself across the carbon-carbon double bond of the indigo. A mean relative standard deviation of 8.6% was obtained using samplers exposed in triplicate, and a correlation coefficient (r) of 0.957 was achieved in parallel measurements using the samplers and a commercial UV ozone instrument. The devices were evaluated in a measurement campaign, mapping spatial and temporal trends of ozone concentrations in a region of southeast Brazil strongly influenced by seasonal agricultural biomass burning, with associated emissions of ozone precursors. Ozone concentrations were highest in rural areas and lowest at an urban site, due to formation during downwind transport and short-term depletion due to titration with nitric oxide. Ozone concentrations showed strong seasonal trends, due to the influences of precursor emissions, relative humidity and solar radiation intensity. Advantages of the technique include ease and speed of use, the ready availability of components, and excellent sensitivity. Achievable temporal resolution of ozone concentrations is 8 hours at an ambient ozone concentration of 3.8 ppb, or 2 hours at a concentration of 15.2 ppb.

  11. The Antarctic Ozone Hole

    ERIC Educational Resources Information Center

    Jones, Anna E.

    2008-01-01

    Since the mid 1970s, the ozone layer over Antarctica has experienced massive destruction during every spring. In this article, we will consider the atmosphere, and what ozone and the ozone layer actually are. We explore the chemistry responsible for the ozone destruction, and learn about why conditions favour ozone destruction over Antarctica. For…

  12. 76 FR 9655 - Approval and Promulgation of Air Quality Implementation Plans; Illinois

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-22

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Illinois AGENCY...) for purposes of attaining the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS or..., as demonstrated by complete, quality-assured air quality data, without the implementation of...

  13. 76 FR 31263 - Approval and Promulgation of Implementation Plans; State of California; Interstate Transport of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-31

    ... (``CAA'') section 110(a)(2)(D)(i) for the 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS... the construction or operation of the facility will not cause or contribute to air pollution in any... demonstration that new or modified sources will not cause or contribute to air pollution in excess of the...

  14. 75 FR 71023 - Approval and Promulgation of State Implementation Plan Revisions; State of North Dakota...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... 6, 2009. Specifically, EPA is approving the portions of the ``Interstate Transport of Air Pollution...)(2)(D)(i) for the 1997 PM 2.5 and 8-hour ozone National Ambient Air Quality Standards (NAAQS). The... finding excuses to avoid requiring North Dakota to do its part to limit air pollution that...

  15. 76 FR 47443 - Approval and Promulgation of State Implementation Plans; State of Colorado; Attainment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-05

    ... in 2010 in one grid cell west of the Fort Collins West monitor. First, in accordance with our... design value at FTCW instead of 86 ppb, no grid cells would have exceeded the 8-hour ozone NAAQS in the... support for this theory, and it is not supported by section 110(a)(1), section 110(l), or any...

  16. 77 FR 14976 - Approval and Promulgation of Implementation Plans; Tennessee; 110(a)(1) and (2) Infrastructure...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-14

    ... a subsequent May 28, 2009, submission, addressed the required infrastructure elements for the 1997 8-hour ozone NAAQS, however the subject of this notice is limited to infrastructure elements 110(a)(2)(C) and (J). All other applicable Tennessee infrastructure elements will be addressed in a...

  17. 77 FR 3213 - Approval and Promulgation of Implementation Plans; Tennessee; 110(a)(1) and (2) Infrastructure...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-23

    ... EPA's public docket visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm... for the 1997 8-hour ozone NAAQS from Tennessee. \\5\\ See Comments of Midwest Environmental Defense Center, dated May 31, 2011. Docket EPA-R05-OAR-2007-1179 (adverse comments on proposals for three...

  18. 76 FR 16358 - Approval and Promulgation of Air Quality Implementation Plans; Connecticut, Maine, New Hampshire...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-23

    ... Hampshire, the media are alerted, through a press release, and the National Weather Service is alerted to issue an Air Quality Advisory through the normal National Weather Service weather alert system. This is... Act (CAA) for the 1997 8-hour ozone national ambient air quality standards (NAAQS). Section 110(a)...

  19. 75 FR 52467 - Approval and Promulgation of Air Quality Implementation Plans: Kentucky; Approval Section 110(a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ...: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: EPA is taking final action to approve a... regulatory requirements, and is consistent with EPA's guidance. EPA is taking final action to approve the... 8-hour ozone NAAQS in the Paducah attainment area. III. Today's Action EPA is taking final action...

  20. 75 FR 56923 - Approval and Promulgation of Implementation Plans; Oklahoma; State Implementation Plan Revisions...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ... otherwise modify redundant or incorrect language within the OAC. The variety of revisions includes..., particulate matter, and sulfur dioxide. The plan developed by a State is referred to as the State... 1997 8-hour ozone NAAQS (70 FR 71612), the State submitted a SIP revision on June 24, 2010, to...

  1. 77 FR 21913 - Approval and Promulgation of State Implementation Plans; Hawaii; Infrastructure Requirements for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-12

    ... NAAQS for fine particulate matter (PM 2.5 ). Section 110(a) of the CAA requires that each State adopt... AGENCY 40 CFR Part 52 Approval and Promulgation of State Implementation Plans; Hawaii; Infrastructure Requirements for the 1997 8-Hour Ozone and the 1997 and 2006 Fine Particulate Matter National Ambient...

  2. 75 FR 72688 - Approval and Promulgation of Implementation Plans; New Mexico; Interstate Transport of Pollution

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-26

    ... paragraph above. The discussion below addresses those comments and our response. Comments from WildEarth... ``Data for 2005-2007 and 2006-2008 reflect violations of the 8-hour ozone NAAQS at the Rocky Flats North... monitoring data for 2005-07 and 2006-08 for the Rocky Flats North monitor reflect violations of the...

  3. 76 FR 36873 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-23

    ..., quality assured, quality controlled, and certified ambient air monitoring data for the years 2008-2010... quality assured, quality controlled, and certified ambient air monitoring data showing that the Atlanta... 8- hour ozone national ambient air quality standards (NAAQS) based on quality assured,...

  4. 77 FR 3144 - Approval and Promulgation of Air Quality Implementation Plans; Missouri; Reasonably Available...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-23

    ...; FRL-9621-1] Approval and Promulgation of Air Quality Implementation Plans; Missouri; Reasonably Available Control Technology (RACT) for the 8-Hour Ozone National Ambient Air Quality Standard (NAAQS... approve these revisions because they enhance the Missouri SIP by improving VOC emission controls...

  5. 78 FR 45112 - Approval and Promulgation of Air Quality Implementation Plans; Missouri; Reasonably Available...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-26

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Missouri; Reasonably Available Control Technology (RACT) for the 8-Hour Ozone National Ambient Air Quality Standard (NAAQS... dated May 4, 2012. The purpose of the SIP revision is to amend Missouri's regulation for the Control...

  6. 76 FR 41123 - Approval and Promulgation of Implementation Plans; Mississippi; 110(a)(1) and (2) Infrastructure...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ...EPA is taking final action to approve the December 7, 2007, submission by the State of Mississippi, through the Mississippi Department of Environmental Quality (MDEQ) as demonstrating that the State meets the implementation plan (SIP) requirements of sections 110(a)(1) and (2) of the Clean Air Act (CAA or the Act) for the 1997 8- hour ozone national ambient air quality standards (NAAQS).......

  7. 40 CFR 52.1491 - Interstate transport.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Nevada § 52.1491 Interstate transport. (a) Approval. On February 7, 2007, the Nevada Division of Environmental Protection submitted the “Nevada State... visibility for the 1997 8-hour ozone and 1997 PM2.5 NAAQS are met by the “Nevada Regional Haze...

  8. 40 CFR 52.1491 - Interstate transport.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Nevada § 52.1491 Interstate transport. (a) Approval. On February 7, 2007, the Nevada Division of Environmental Protection submitted the “Nevada State... visibility for the 1997 8-hour ozone and 1997 PM2.5 NAAQS are met by the “Nevada Regional Haze...

  9. Earth's Endangered Ozone

    ERIC Educational Resources Information Center

    Panofsky, Hans A.

    1978-01-01

    Included are (1) a discussion of ozone chemistry; (2) the effects of nitrogen fertilizers, fluorocarbons, and high level aircraft on the ozone layer; and (3) the possible results of a decreasing ozone layer. (MR)

  10. A direct sensitivity approach to predict hourly ozone resulting from compliance with the National Ambient Air Quality Standard.

    PubMed

    Simon, Heather; Baker, Kirk R; Akhtar, Farhan; Napelenok, Sergey L; Possiel, Norm; Wells, Benjamin; Timin, Brian

    2013-03-05

    In setting primary ambient air quality standards, the EPA's responsibility under the law is to establish standards that protect public health. As part of the current review of the ozone National Ambient Air Quality Standard (NAAQS), the US EPA evaluated the health exposure and risks associated with ambient ozone pollution using a statistical approach to adjust recent air quality to simulate just meeting the current standard level, without specifying emission control strategies. One drawback of this purely statistical concentration rollback approach is that it does not take into account spatial and temporal heterogeneity of ozone response to emissions changes. The application of the higher-order decoupled direct method (HDDM) in the community multiscale air quality (CMAQ) model is discussed here to provide an example of a methodology that could incorporate this variability into the risk assessment analyses. Because this approach includes a full representation of the chemical production and physical transport of ozone in the atmosphere, it does not require assumed background concentrations, which have been applied to constrain estimates from past statistical techniques. The CMAQ-HDDM adjustment approach is extended to measured ozone concentrations by determining typical sensitivities at each monitor location and hour of the day based on a linear relationship between first-order sensitivities and hourly ozone values. This approach is demonstrated by modeling ozone responses for monitor locations in Detroit and Charlotte to domain-wide reductions in anthropogenic NOx and VOCs emissions. As seen in previous studies, ozone response calculated using HDDM compared well to brute-force emissions changes up to approximately a 50% reduction in emissions. A new stepwise approach is developed here to apply this method to emissions reductions beyond 50% allowing for the simulation of more stringent reductions in ozone concentrations. Compared to previous rollback methods, this

  11. Effect of photoperiodic pretreatments on symptom development in plants exposed to ozone

    SciTech Connect

    Godish, T.

    1980-01-01

    Results presented in this report on the effects of photoperiodic pretreatment on ozone sensitivity of plants are significantly different from the lone previous report on this subject. Juhren et al (5) studied the effects of photoperiodic pretreatments on sensitivity of pinto beans exposed to oxidants (presumably ozone). They reported that pinto bean plants were most sensitive to oxidants under short photoperiods (8 hours) and least sensitive to long photoperiods (16 hours). In studies of tomato and peas presented in this report, minimum sensitivity for tomato was observed under the 8 hour pretreatment; for peas minimum sensitivity was observed for the 8 and 10 hour pretreatments. Maximum sensitivity for tomato was observed for the 12-hour photoperiodic pretreatment; peas showed maximum sensitivity under the 14-hour photoperiod. 7 references, 1 table.

  12. Effects of ozone and peroxyacetyl nitrate on polar lipids and fatty acids in leaves of morning glory and kidney bean. [Pharbitis nil; Phaseolus vulgaris

    SciTech Connect

    Nouchi, Isamu; Toyama, Susumu Ochanomizu Univ., Tokyo )

    1988-07-01

    To compare the effects of ozone and peroxyacetyl nitrate (PAN) on leaf lipids, fatty acids and malondialdehyde (MDA), morning glory (Pharbitis nil Choisy cv Scarlet O'Hara) and kidney bean (Phaseolus vulgaris L. cv Gintebo) plants were exposed to either ozone (0.15 microliter per liter for 8 hours) or PAN (0.10 microliter per liter for up to 8 hours). Ozone increased phospholipids in morning glory and decreased in kidney bean at the initial stage (2-4 hours) of exposure, while it scarcely changed glycolipids, the unsaturated fatty acids, and MDA in both plants. A large reduction of glycolipids occurred 1 day after ozone exposure in both plants. PAN caused marked drops in phospholipids and glycolipids in kidney bean at relatively late stage (6-8 hours) of exposure, while it increased phosphatidic acid and decreased the unsaturated fatty acids, an increase which was accompanied by a large increase in MDA. These results suggest that ozone may not directly oxidize unsaturated fatty acids at the initial stage of exposure, but may alter polar lipid metabolism, particularly phospholipids. On the other hand, PAN may abruptly and considerably degrade phospholipids and glycolipids by peroxidation or hydrolysis at the late stage of exposure. The present study shows that ozone and PAN affect polar lipids in different manners.

  13. Comparative Effects of Gamma Irradiation and Ozone Treatment on Hygienic Quality of Korean Red Ginseng Powder

    NASA Astrophysics Data System (ADS)

    Byun, Myung-Woo; Yook, Hong-Sun; Kang, Il-Jun; Chung, Cha-Kwon; Kwon, Joong-Ho; Choi, Kang-Ju

    1998-06-01

    For the purpose of improving hygienic quality of Korean red ginseng powder, the comparative effects of gamma irradiation and ozone treatment on the microbial and physicochemical properties were investigated. Gamma irradiation at 7.5 kGy resulted in sterilization of total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the microorganisms of the red ginseng powder. Physicochemical properties including compositions of the red ginseng saponin (ginsenosides) and fatty acids, pH and hydrogen doanting activity were not significantly changed by gamma irradiation, whereas, ozone treatment caused significant changes in fatty acid compositions, TBA value, pH, acidity and hydrogen donating activity. The results from this study led us to conclude that gamma irradiation was more effective than ozone treatment both for the improvement of hygienic quality and for the maintenance of physicochemical quality of red ginseng powder.

  14. Ozone Hole Over Antarctica

    NASA Technical Reports Server (NTRS)

    2002-01-01

    These images from the Total Ozone Mapping Spectrometer (TOMS) show the progressive depletion of ozone over Antarctica from 1979 to 1999. This 'ozone hole' has extended to cover an area as large as 10.5 million square miles in September 1998. The previous record of 10.0 million square miles was set in 1996. The Antarctic ozone hole develops each year between late August and early October. Regions with higher levels of ozone are shown in red. NASA and NOAA instruments have been measuring Antarctic ozone levels since the early 1970s. Large regions of depleted ozone began to develop over Antarctica in the early 1980s. Ozone holes of substantial size and depth are likely to continue to form during the next few years, scientists hope to see a reduction in ozone loss as levels of ozone-destroying CFCs (chlorofluorocarbons) are gradually reduced. Credit: Images by Greg Shirah, NASA Goddard Space Flight Center Scientific Visualization Studio

  15. The Antarctic ozone hole

    NASA Astrophysics Data System (ADS)

    Molina, Mario J.

    Observations of Antarctic ozone levels and the discovery of a hole in the Antarctic region are examined. The effects of chlorofluorocarbons (CFCs) on the level of stratospheric ozone are analyzed. Three cycles explaining the cause of ozone depletion in the poles are proposed. A comparison of field data and proposed depletion cycles reveals that the chemical origin of the ozone hole is due to CFCs. The potential global effects of the Antarctic ozone hole are discussed.

  16. Long-Term Exposure to Ozone and Life Expectancy in the United States, 2002 to 2008.

    PubMed

    Li, Chaoyang; Balluz, Lina S; Vaidyanathan, Ambarish; Wen, Xiao-Jun; Hao, Yongping; Qualters, Judith R

    2016-02-01

    Long-term exposure to ground-level ozone is associated with increased risk of morbidity and mortality. The association remains uncertain between long-term exposure to ozone and life expectancy. We assessed the associations between seasonal mean daily 8-hour maximum (8-hr max) ozone concentrations measured during the ozone monitoring seasons and life expectancy at birth in 3109 counties of the conterminous U.S. during 2002 to 2008. We used latent class growth analysis to identify latent classes of counties that had distinct mean levels and rates of change in ozone concentrations over the 7-year period and used linear regression analysis to determine differences in life expectancy by ozone levels. We identified 3 classes of counties with distinct seasonal mean daily 8-hr max ozone concentrations and rates of change. When compared with the counties with the lowest ozone concentrations, the counties with the highest ozone concentrations had 1.7- and 1.4-year lower mean life expectancy in males and females (both P < 0.0001), respectively. The associations remained statistically significant after controlling for potential confounding effects of seasonal mean PM2.5 concentrations and other selected environmental, demographic, socio-economic, and health-related factors (both P < 0.0001). A 5 ppb higher ozone concentration was associated with 0.25 year lower life expectancy in males (95% CI: -0.30 to -0.19) and 0.21 year in females (95% CI: -0.25 to -0.17). We identified 3 classes of counties with distinct mean levels and rates of change in ozone concentrations. Our findings suggest that long-term exposure to a higher ozone concentration may be associated with a lower life expectancy.

  17. Long-Term Exposure to Ozone and Life Expectancy in the United States, 2002 to 2008

    PubMed Central

    Li, Chaoyang; Balluz, Lina S.; Vaidyanathan, Ambarish; Wen, Xiao-Jun; Hao, Yongping; Qualters, Judith R.

    2016-01-01

    Abstract Long-term exposure to ground-level ozone is associated with increased risk of morbidity and mortality. The association remains uncertain between long-term exposure to ozone and life expectancy. We assessed the associations between seasonal mean daily 8-hour maximum (8-hr max) ozone concentrations measured during the ozone monitoring seasons and life expectancy at birth in 3109 counties of the conterminous U.S. during 2002 to 2008. We used latent class growth analysis to identify latent classes of counties that had distinct mean levels and rates of change in ozone concentrations over the 7-year period and used linear regression analysis to determine differences in life expectancy by ozone levels. We identified 3 classes of counties with distinct seasonal mean daily 8-hr max ozone concentrations and rates of change. When compared with the counties with the lowest ozone concentrations, the counties with the highest ozone concentrations had 1.7- and 1.4-year lower mean life expectancy in males and females (both P < 0.0001), respectively. The associations remained statistically significant after controlling for potential confounding effects of seasonal mean PM2.5 concentrations and other selected environmental, demographic, socio-economic, and health-related factors (both P < 0.0001). A 5 ppb higher ozone concentration was associated with 0.25 year lower life expectancy in males (95% CI: −0.30 to −0.19) and 0.21 year in females (95% CI: −0.25 to −0.17). We identified 3 classes of counties with distinct mean levels and rates of change in ozone concentrations. Our findings suggest that long-term exposure to a higher ozone concentration may be associated with a lower life expectancy. PMID:26886595

  18. How does climate change contribute to surface ozone change over the United States?

    NASA Astrophysics Data System (ADS)

    Murazaki, K.; Hess, P.

    2006-03-01

    The impact of climate change on U.S. surface ozone levels is investigated. We simulated two 10 year periods using the global chemical transport model MOZART-2 (Model of Ozone and Related chemical Tracers version 2): 1990-2000 and 2090-2100. In each case, MOZART-2 is driven by meteorology from the National Center for Atmospheric Research (NCAR) coupled Climate Systems Model (CSM) 1.0 forced with the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A1 scenario. During both periods the chemical emissions are fixed at 1990s levels, so that only changes in climate are allowed to impact ozone. The simulated surface ozone concentration during the 1990s is compared with observations from the Environmental Protection Agency's Aerometric Information Retrieval System (EPA AIRS) monitoring sites. Model-measurement correlations are high, but MOZART-2 overpredicts ozone especially over the eastern United States. The impact of climate change is calculated separately for background ozone and for the ozone generated through U.S. NOx emissions. Our results show that the response of ozone to climate change in polluted regions is not the same as in remote regions. MOZART-2 predicts a 0-2 ppbv decrease in background ozone in the future simulation over the United States but an increase in ozone produced internally within the United States of up to 6 ppbv. The decrease in background ozone is attributed to a future decrease in the lifetime of ozone in regions of low NOx. Over the western United States the decrease in background ozone approximately cancels the increase in locally produced ozone. As a result, the main impact of future climate change on ozone is centered over the eastern United States, where future ozone increases up to 5 ppbv. We predict that in the future over the northeast United States, up to 12 additional days each year will exceed the maximum daily 8-hour averaged ozone limit of 80 ppbv. Various climatic factors are

  19. Antarctic Ozone Hole, 2000

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Each spring the ozone layer over Antarctica nearly disappears, forming a 'hole' over the entire continent. The hole is created by the interaction of some man-made chemicals-freon, for example-with Antarctica's unique weather patterns and extremely cold temperatures. Ozone in the stratosphere absorbs ultraviolet radiation from the sun, thereby protecting living things. Since the ozone hole was discovered many of the chemicals that destroy ozone have been banned, but they will remain in the atmosphere for decades. In 2000, the ozone hole grew quicker than usual and exceptionally large. By the first week in September the hole was the largest ever-11.4 million square miles. The top image shows the average total column ozone values over Antarctica for September 2000. (Total column ozone is the amount of ozone from the ground to the top of the atmosphere. A relatively typical measurement of 300 Dobson Units is equivalent to a layer of ozone 0.12 inches thick on the Earth's surface. Levels below 220 Dobson Units are considered to be significant ozone depletion.) The record-breaking hole is likely the result of lower than average ozone levels during the Antarctic fall and winter, and exceptionally cold temperatures. In October, however (bottom image), the hole shrank dramatically, much more quickly than usual. By the end of October, the hole was only one-third of it's previous size. In a typical year, the ozone hole does not collapse until the end of November. NASA scientists were surprised by this early shrinking and speculate it is related to the region's weather. Global ozone levels are measured by the Total Ozone Mapping Spectrometer (TOMS). For more information about ozone, read the Earth Observatory's ozone fact sheet, view global ozone data and see these ozone images. Images by Greg Shirah, NASA GSFC Scientific Visualization Studio.

  20. Plasmadynamic ozone generator

    NASA Astrophysics Data System (ADS)

    Gordeev, Yu. N.; Ogurechnikov, V. A.; Chizhov, Yu. L.

    2009-10-01

    The formation of ozone in a low-temperature supersonic flow of a mixture of air and partly dissociated oxygen supplied from a discharge plasmatron has been experimentally studied. For an oxygen mass fraction of 1.1% in the total gas flow supplied to this ozone generator, an ozone-air mixture containing 4.88 × 10-3 kg/m3 ozone is obtained at a specific energy consumption of 25.8 MJ/(kg ozone). In this regime, the ozone generator could operate for several dozen minutes.

  1. The Antarctic ozone hole

    NASA Astrophysics Data System (ADS)

    Jones, Anna E.

    2008-07-01

    Since the mid 1970s, the ozone layer over Antarctica has experienced massive destruction during every spring. In this article, we will consider the atmosphere, and what ozone and the ozone layer actually are. We explore the chemistry responsible for the ozone destruction, and learn about why conditions favour ozone destruction over Antarctica. For the historical perspective, the events leading up to the discovery of the 'hole' are presented, as well as the response from the international community and the measures taken to protect the ozone layer now and into the future.

  2. Gridded global surface ozone metrics for atmospheric chemistry model evaluation

    NASA Astrophysics Data System (ADS)

    Sofen, E. D.; Bowdalo, D.; Evans, M. J.; Apadula, F.; Bonasoni, P.; Cupeiro, M.; Ellul, R.; Galbally, I. E.; Girgzdiene, R.; Luppo, S.; Mimouni, M.; Nahas, A. C.; Saliba, M.; Tørseth, K.

    2016-02-01

    The concentration of ozone at the Earth's surface is measured at many locations across the globe for the purposes of air quality monitoring and atmospheric chemistry research. We have brought together all publicly available surface ozone observations from online databases from the modern era to build a consistent data set for the evaluation of chemical transport and chemistry-climate (Earth System) models for projects such as the Chemistry-Climate Model Initiative and Aer-Chem-MIP. From a total data set of approximately 6600 sites and 500 million hourly observations from 1971-2015, approximately 2200 sites and 200 million hourly observations pass screening as high-quality sites in regionally representative locations that are appropriate for use in global model evaluation. There is generally good data volume since the start of air quality monitoring networks in 1990 through 2013. Ozone observations are biased heavily toward North America and Europe with sparse coverage over the rest of the globe. This data set is made available for the purposes of model evaluation as a set of gridded metrics intended to describe the distribution of ozone concentrations on monthly and annual timescales. Metrics include the moments of the distribution, percentiles, maximum daily 8-hour average (MDA8), sum of means over 35 ppb (daily maximum 8-h; SOMO35), accumulated ozone exposure above a threshold of 40 ppbv (AOT40), and metrics related to air quality regulatory thresholds. Gridded data sets are stored as netCDF-4 files and are available to download from the British Atmospheric Data Centre (doi: 10.5285/08fbe63d-fa6d-4a7a-b952-5932e3ab0452). We provide recommendations to the ozone measurement community regarding improving metadata reporting to simplify ongoing and future efforts in working with ozone data from disparate networks in a consistent manner.

  3. Ozone-induced changes in the expression of the genes encoding regulatory enzymes for polyamine, ethylene and phenylpropanoid metabolisms in ozone tolerant and sensitive birch (Betula pendula Roth) clones

    SciTech Connect

    Talvinen, J.; Pellinen, R.; Eloranta, T.; Kangasjaervi, J. ); Julkunen-Tiitto, R. ); Karjalainen, R. )

    1993-05-01

    Increase in the atmospheric ozone concentration has been shown to affect plant growth in several ways; from decreased photosynthetic activity to visible dames and in some extreme situations even to tissue death. Plants protect themselves from the damaging effect of ozone by inducing several physiological reactions. For example, increases in ethylene production, polyamine and phenylpropanoid synthesis have been observed in stress reaction induced by increased atmospheric ozone. similar changes, which are often called general stress reactions, are induced by several other biotic and which are often called general stress reactions, are induced by several other biontic and abiotic factors, e.g., plant pathogens. It has been shown previously that the production of stress ethylene can partly be responsible for the ozone damage formation in plants. Induction of stress-polyamine synthesis can prevent ethylene formation and is higher in some ozone-tolerant plants. We have exposed ozone sensitive and resistant birch clones to ozone (150 ppb. 8 hours) to analyze ozone-induced changes in the phenylpropanoid and polyamine metabolisms and gene expression. The polyamine and phenylpropanoid contents of the experimental material are currently being analyzed and the results will be presented. We have also cloned by PCR gene probes for birch ACC-synthase, arginine decarboxylase (ADC) and phenylalanine ammoniumlyase (PAL) genes. Results will be presented where the probes have been used to analyze ozone-induced expression of the genes in the birch clones.

  4. Reference and Equivalent Methods Used to Measure National Ambient Air Quality Standards (NAAQS) Criteria Air Pollutants - Volume I

    EPA Science Inventory

    There are a number of Federal Reference Method (FRM) and Federal Equivalent Method (FEM) systems used to monitor the six criteria air pollutants (Lead [Pb], Carbon Monoxide [CO], Sulfur Dioxide [SO2], Nitrogen Dioxide [NO2], Ozone [O3], Particulate Matter [PM]) to determine if an...

  5. Basic Ozone Layer Science

    EPA Pesticide Factsheets

    Learn about the ozone layer and how human activities deplete it. This page provides information on the chemical processes that lead to ozone layer depletion, and scientists' efforts to understand them.

  6. Ozone Trend Detectability

    NASA Technical Reports Server (NTRS)

    Campbell, J. W. (Editor)

    1981-01-01

    The detection of anthropogenic disturbances in the Earth's ozone layer was studied. Two topics were addressed: (1) the level at which a trend in total ozoning is detected by existing data sources; and (2) empirical evidence in the prediction of the depletion in total ozone. Error sources are identified. The predictability of climatological series, whether empirical models can be trusted, and how errors in the Dobson total ozone data impact trend detectability, are discussed.

  7. Ozone Layer Observations

    NASA Technical Reports Server (NTRS)

    McPeters, Richard; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    The US National Aeronautics and Space Administration (NASA) has been monitoring the ozone layer from space using optical remote sensing techniques since 1970. With concern over catalytic destruction of ozone (mid-1970s) and the development of the Antarctic ozone hole (mid-1980s), long term ozone monitoring has become the primary focus of NASA's series of ozone measuring instruments. A series of TOMS (Total Ozone Mapping Spectrometer) and SBUV (Solar Backscatter Ultraviolet) instruments has produced a nearly continuous record of global ozone from 1979 to the present. These instruments infer ozone by measuring sunlight backscattered from the atmosphere in the ultraviolet through differential absorption. These measurements have documented a 15 Dobson Unit drop in global average ozone since 1980, and the declines in ozone in the antarctic each October have been far more dramatic. Instruments that measure the ozone vertical distribution, the SBUV and SAGE (Stratospheric Aerosol and Gas Experiment) instruments for example, show that the largest changes are occurring in the lower stratosphere and upper troposphere. The goal of ozone measurement in the next decades will be to document the predicted recovery of the ozone layer as CFC (chlorofluorocarbon) levels decline. This will require a continuation of global measurements of total column ozone on a global basis, but using data from successor instruments to TOMS. Hyperspectral instruments capable of measuring in the UV will be needed for this purpose. Establishing the relative roles of chemistry and dynamics will require instruments to measure ozone in the troposphere and in the stratosphere with good vertical resolution. Instruments that can measure other chemicals important to ozone formation and destruction will also be needed.

  8. Ozone drinking water treatment handbook

    SciTech Connect

    Rice, R.G.

    1990-01-01

    This book explains how ozone can be used to provide primary disinfection, while minimizing halogenated by-products. This is of use to those who design pilot plant studies in full scale ozone plants-and those who employ ozone and regulatory personnel. Detailed section on components of an ozonization system outlines feed gas preparation (air and oxygen), ozone generation, ozone contacting, ozone off gas destruction, monitoring and control of ozonation systems, engineering aspects of ozone, cost factors in ozone technology, case histories (European and U.S.).

  9. Ozone Antimicrobial Efficacy

    EPA Science Inventory

    Ozone is a potent germicide that has been used extensively for water purification. In Europe, 90 percent of the municipal water systems are treated with ozone, and in France, ozone has been used to treat drinking water since 1903. However, there is limited information on the bioc...

  10. Control strategy optimization for attainment and exposure mitigation: case study for ozone in Macon, Georgia.

    PubMed

    Cohan, Daniel S; Tian, Di; Hu, Yongtao; Russell, Armistead G

    2006-09-01

    Implementation of more stringent 8-hour ozone standards has led the U.S. Environmental Protection Agency to designate nonattainment status to 474 counties nationwide, many of which had never previously violated air quality standards. As states select emission control measures to achieve attainment in these regions, their choices pose significant implications to local economies and the health of their citizens. Considering a case study of one such nonattainment region, Macon, Georgia, we develop a menu of potential controls that could be implemented locally or in neighboring parts of the state. The control menu offers the potential to control about 20-35% of ozone precursor emissions in most Georgia regions, but marginal costs increase rapidly beyond 15-20%. We link high-order ozone sensitivities with the control menu to identify cost-optimized strategies for achieving attainment and for alternative goals such as reducing spatially averaged or population-weighted ozone concentrations. Strategies targeted toward attainment of Macon ozone would prioritize local reductions of nitrogen oxides, whereas controls in the more densely populated Atlanta region are shown to be more effective for reducing statewide potential population exposure to ozone. A U.S. EPA-sanctioned approach for demonstrating ozone attainment with photochemical models is shown to be highly dependent on the choice of a baseline period and may not foster optimal strategies for assuring attainment and protecting human health.

  11. Projections of Future Summertime Ozone over the U.S.

    SciTech Connect

    Pfister, G. G.; Walters, Stacy; Lamarque, J. F.; Fast, Jerome D.; Barth, Mary; Wong, John; Done, James; Holland, Greg; Bruyere, Cindy

    2014-05-05

    This study uses a regional fully coupled chemistry-transport model to assess changes in surface ozone over the summertime U.S. between present and a 2050 future time period at high spatial resolution (12 km grid spacing) under the SRES A2 climate and RCP8.5 anthropogenic pre-cursor emission scenario. The impact of predicted changes in climate and global background ozone is estimated to increase surface ozone over most of the U.S; the 5th - 95th percentile range for daily 8-hour maximum surface ozone increases from 31-79 ppbV to 30-87 ppbV between the present and future time periods. The analysis of a set of meteorological drivers suggests that these mostly will add to increasing ozone, but the set of simulations conducted does not allow to separate this effect from that through enhanced global background ozone. Statistically the most robust positive feedbacks are through increased temperature, biogenic emissions and solar radiation. Stringent emission controls can counteract these feedbacks and if considered, we estimate large reductions in surface ozone with the 5th-95th percentile reduced to 27-55 ppbV. A comparison of the high-resolution projections to global model projections shows that even though the global model is biased high in surface ozone compared to the regional model and compared to observations, both the global and the regional model predict similar changes in ozone between the present and future time periods. However, on smaller spatial scales, the regional predictions show more pronounced changes between urban and rural regimes that cannot be resolved at the coarse resolution of global model. In addition, the sign of the changes in overall ozone mixing ratios can be different between the global and the regional predictions in certain regions, such as the Western U.S. This study confirms the key role of emission control strategies in future air quality predictions and demonstrates the need for considering degradation of air quality with future

  12. Response of macaque bronchiolar epithelium to ambient concentrations of ozone.

    PubMed Central

    Harkema, J. R.; Plopper, C. G.; Hyde, D. M.; St George, J. A.; Wilson, D. W.; Dungworth, D. L.

    1993-01-01

    Recently, we reported that exposure to ambient concentrations of ozone, near the U.S. National Ambient Air Quality Standard (0.12 ppm), induced significant nasal epithelial lesions in a non-human primate, the bonnet monkey. The present study defines the effects of ambient concentrations of ozone on the surface epithelium lining respiratory bronchioles and on the underlying bronchiolar interstitium in these same monkeys. Bonnet monkeys were exposed to filtered air or to 0.15 or 0.30 ppm ozone 8 hours/day for 6 or 90 days. At the end of exposures, monkeys were anesthetized and killed by exsanguination. Microdissected bronchiolar airways of infusion-fixed lungs were evaluated morphometrically by light microscopy and quantitatively by scanning and transmission electron microscopy for ozone-induced epithelial changes. Hyperplasia of nonciliated, cuboidal epithelial cells and intraluminal accumulation of macrophages characterized ozone-induced lesions in respiratory bronchioles. There were no significant differences in epithelial thickness or cell numbers among ozone-exposed groups. Ozone-exposed epithelium was composed of 80% cuboidal and 20% squamous cells compared with 40% cuboidal and 60% squamous cells in filtered air controls. In addition, the arithmetic mean thickness of the surface epithelium, a measure of tissue mass per unit area of basal lamina, was significantly increased in all of the ozone-exposed groups. The number of cuboidal epithelial cells per surface area of basal lamina was increased above control values by 780% after 6 days exposure to 0.15 ppm, 777% after 90 days to 0.15 ppm, and 996% after 90 days exposure to 0.30 ppm. There was also a significant ozone-induced increase in the thickness of the bronchiolar interstitium that was due to an increase in both cellular and acellular components. These results demonstrate that exposure to low ambient concentrations of ozone, near the current. National Ambient Air Quality Standard, induces pulmonary lesions

  13. Spatial and temporal patterns of ozone in the high elevation ecosystems of the Colorado Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Liptzin, D.; Helmig, D.

    2015-12-01

    Tropospheric ozone is regulated by the US EPA to protect human health and welfare. Because the precursors to ozone formation largely come from transportation and industrial activity, ozone has typically been thought of as an urban pollution problem. However, there is growing concern about increased ozone concentrations in rural areas. Surprisingly high ozone concentrations have been measured in the high elevation Rocky Mountain ecosystems in the Front Range of Colorado. The annual median ozone mixing ratios over the past decade at three high elevation monitoring stations ranged from 47 to 53 ppbv. The hourly ozone mixing ratio typically exceeds 100 ppbv at some point every year at these sites. The number of days where the ozone mixing ratio exceeded the current 8 hour US EPA National Ambient Air Quality Standard of 75 ppb has ranged from 0 to 25 since 1987 at the monitoring site in Rocky Mountain National Park. A comparison with lower elevation sites suggests that ozone mixing ratios generally increase with elevation. In addition, the diurnal and seasonal variability of ozone decreases with elevation. Along an elevational gradient from the plains to the tundra, the tundra site had the highest median values and the least variability of any site. The seasonal pattern at these high elevation sites is also distinct as the maximum mixing ratios occur in the spring in contrast to the summer maximum typically observed in urban areas. While there have been relatively small changes in concentration in the measured data record going back a few decades, modeling suggests that ozone mixing ratios have almost doubled over the last one hundred years in Colorado. A plethora of studies has shown that elevated ozone damages foliage, with sensitive species showing effect at levels exceeding 35-40 ppbv. Since ozone levels in these high elevation ecosystems are clearly above that, we believe that they have been and will continue to be severely affected by elevated ozone. It is not

  14. Overview of ozone bleaching

    SciTech Connect

    Sonnenberg, L.B.

    1995-12-31

    The potential impact of the pulp and paper industry on the environment may be reduced by replacing chlorine-based bleaching reagents with ozone. The reactivity of ozone coupled with the heterogeneity of pulp allows many types of reactions to occur during pulp bleaching. Ozone cleaves the aromatic rings and side chain double bonds in lignin in Criegee-type mechanisms. Activated carbon-hydrogen bonds are fragmented in lignin side chains, as well as Cl carbons of {beta}-glycosides, by way of a 1,3 dipolar insertion forming a hydrotrioxide intermediate. Ozone also attacks carbohydrates at acetal oxygens, depolymerizing at the glycosidic bond. Unsaturated sites are ozonated before aliphatic sites resulting in a predominance of lignin reactions over carbohydrate reactions until lignin is substantially removed from the pulp. Important factors in the successful application of ozone bleaching include minimizing ozone decomposition and other secondary reactions, reducing exposure of cellulose to high concentrations of ozone and radicals, and promoting uniform exposure of ozone to lignin. The quantity of chlorinated organic compounds in effluents can be drastically reduced by replacing chlorine-based bleaching reagents with ozone; less organochlorine is formed and there can be greater recycle of bleach plant wastes back to the recovery cycle. Recycling of bleach plant waste also reduces total organic loading in the effluent. The toxicity of ozone filtrates is variable compared to conventional filtrates and depends on several parameters including bleaching conditions, biological treatment, and target organisms.

  15. Changes in US background ozone due to global anthropogenic emissions from 1970 to 2020

    NASA Astrophysics Data System (ADS)

    Nopmongcol, Uarporn; Jung, Jaegun; Kumar, Naresh; Yarwood, Greg

    2016-09-01

    Estimates of North American and US Background (NAB and USB) ozone (O3) are critical in setting and implementing the US National Ambient Air Quality Standards (NAAQS) and therefore influence population exposure to O3 across the US. NAB is defined as the O3 concentration in the absence of anthropogenic O3 precursor emissions from North America whereas USB excludes anthropogenic emissions inside the US alone. NAB and USB vary geographically and with time of year. Analyses of O3 trends at rural locations near the west coast suggest that background O3 is rising in response to increasing non-US emissions. As the O3 NAAQS is lowered, rising background O3 would make attaining the NAAQS more difficult. Most studies of changing US background O3 have inferred trends from observations whereas air quality management decisions tend to rely on models. Thus, it is important that the models used to develop O3 management strategies are able to represent the changes in background O3 in order to increase confidence that air quality management strategies will succeed. We focus on how changing global emissions influence USB rather than the effects of inter-annual meteorological variation or long-term climate change. We use a regional model (CAMx) nested within a global model (GEOS-Chem) to refine our grid resolution over high terrain in the western US and near US borders where USB tends to be higher. We determine USB from CAMx simulations that exclude US anthropogenic emissions. Over five decades, from 1970 to 2020, estimated USB for the annual fourth highest maximum daily 8-h average O3 (H4MDA8) in the western US increased from mostly in the range of 40-55 ppb to 45-60 ppb, but remained below 45 ppb in the eastern US. USB increases in the southwestern US are consistent with rising emissions in Asia and Mexico. USB decreases in the northeast US after 1990 follow declining Canadian emissions. Our results show that the USB increases both for the top 30 MDA8 days and the H4MDA8 (the former

  16. Spring polar ozone behavior

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.

    1992-01-01

    Understanding of the springtime behavior of polar stratospheric ozone as of mid 1990 is summarized. Heterogeneous reactions on polar stratospheric clouds as hypothesis for ozone loss are considered and a simplified description of the behavior of Antarctic ozone in winter and spring is given. Evidence that the situation is more complicated than described by the theory is produced. Many unresolved scientific issues remain and some of the most important problems are identified. Ozone changes each spring since 1979 have clearly established for the first time that man made chlorine compounds influence stratospheric ozone. Long before important advances in satellite and in situ investigations, it was Dobson's decision to place a total ozone measuring spectrometer at Halley Bay in Antarctica during the International Geophysical Year and subsequent continuous monitoring which led to the discovery that ozone was being destroyed each spring by chlorine processed by polar stratospheric clouds.

  17. Ozone and the stratosphere

    NASA Technical Reports Server (NTRS)

    Shimazaki, Tatsuo

    1987-01-01

    It is shown that the stratospheric ozone is effective in absorbing almost all radiation below 300 nm at heights below 300 km. The distribution of global ozone in the troposphere and the lower stratosphere, and the latitudinal variations of the total ozone column over four seasons are considered. The theory of the ozone layer production is discussed together with catalytic reactions for ozone loss and the mechanisms of ozone transport. Special attention is given to the anthropogenic perturbations, such as SST exhaust gases and freon gas from aerosol cans and refrigerators, that may cause an extensive destruction of the stratospheric ozone layer and thus have a profound impact on the world climate and on life.

  18. Variability and sources of surface ozone at rural sites in Nevada, USA: Results from two years of the Nevada Rural Ozone Initiative.

    PubMed

    Fine, Rebekka; Miller, Matthieu B; Burley, Joel; Jaffe, Daniel A; Pierce, R Bradley; Lin, Meiyun; Gustin, Mae Sexauer

    2015-10-15

    Ozone (O3) has been measured at Great Basin National Park (GBNP) since September 1993. GBNP is located in a remote, rural area of eastern Nevada. Data indicate that GBNP will not comply with a more stringent National Ambient Air Quality Standard (NAAQS) for O3, which is based upon the 3-year average of the annual 4th highest Maximum Daily 8-h Average (MDA8) concentration. Trend analyses for GBNP data collected from 1993 to 2013 indicate that MDA8 O3 increased significantly for November to February, and May. The greatest increase was for May at 0.38, 0.35, and 0.46 ppb yr(-1) for the 95th, 50th, and 5th percentiles of MDA8 O3 values, respectively. With the exception of GBNP, continuous O3 monitoring in Nevada has been limited to the greater metropolitan areas. Due to the limited spatial detail of O3 measurements in rural Nevada, a network of rural monitoring sites was established beginning in July 2011. For a period ranging from July 2011 to June 2013, maximum MDA8 O3 at 6 sites occurred in the spring and summer, and ranged from 68 to 80ppb. Our analyses indicate that GBNP, in particular, is ideally positioned to intercept air containing elevated O3 derived from regional and global sources. For the 2 year period considered here, MDA8 O3 at GBNP was an average of 3.1 to 12.6 ppb higher than at other rural Nevada sites. Measured MDA8 O3 at GBNP exceeded the current regulatory threshold of 75 ppb on 7 occasions. Analyses of synoptic conditions, model tracers, and air mass back-trajectories on these days indicate that stratospheric intrusions, interstate pollution transport, wildfires, and Asian pollution contributed to elevated O3 observed at GBNP. We suggest that regional and global sources of ozone may pose challenges to achieving a more stringent O3 NAAQS in rural Nevada.

  19. Key drivers of Western U.S. surface ozone variability during 1980-2050: From background trends to extreme transport events

    NASA Astrophysics Data System (ADS)

    Lin, M.

    2014-12-01

    The U.S. Environmental Protection Agency is proposing to lower the National Ambient Air Quality Standard (NAAQS) for ground-level ozone from 75 ppbv to a range of 60-70 ppbv on the basis of the latest health evidence. Rising Asian emissions, more frequent wildfires, and poorly understood deep stratospheric intrusions may pose challenges to achieving more stringent ozone standards over high-elevation Western U.S. (WUS) regions. Understanding the factors driving daily to decadal variability in sources of ozone is thus relevant to an effective implementation of the ozone NAAQS in WUS states. Here I present a detailed analysis of WUS surface ozone variability during 1980-2050, based on observations and a suite of chemistry-climate model simulations designed to isolate the role of changes in meteorology, background, STT, wildfires, methane, and Asian vs. North American anthropogenic emissions. Our analysis identifies the key role of stratospheric intrusion frequency on year-to-year variability in springtime high-ozone events measured at high-elevation WUS sites. We show more frequent late spring deep stratospheric intrusions when the polar jet stream meanders towards the southwestern United States, as occurs following strong La Niña conditions. Fewer and weaker intrusion events followed the pronounced positive phase of the Arctic Oscillation in response to volcanic aerosols from the 1991 eruption of Mt. Pinatubo. With Asian emissions, global methane, and meteorology varying with time, the model simulates a background ozone increase of 0.20-0.45 ppb yr-1 (P≤0.01) at high-elevation WUS sites for spring during 1988-2012. With global methane and meteorology varying with time, the model shows an increasing ozone trend of 0.1-0.2 ppb yr-1 in spring (0.01ozone over the northeastern U.S., with implications for

  20. Ozone therapy in periodontics.

    PubMed

    Gupta, G; Mansi, B

    2012-02-22

    Gingival and Periodontal diseases represent a major concern both in dentistry and medicine. The majority of the contributing factors and causes in the etiology of these diseases are reduced or treated with ozone in all its application forms (gas, water, oil). The beneficial biological effects of ozone, its anti-microbial activity, oxidation of bio-molecules precursors and microbial toxins implicated in periodontal diseases and its healing and tissue regeneration properties, make the use of ozone well indicated in all stages of gingival and periodontal diseases. The primary objective of this article is to provide a general review about the clinical applications of ozone in periodontics. The secondary objective is to summarize the available in vitro and in vivo studies in Periodontics in which ozone has been used. This objective would be of importance to future researchers in terms of what has been tried and what the potentials are for the clinical application of ozone in Periodontics.

  1. Ozone therapy in periodontics

    PubMed Central

    Gupta, G; Mansi, B

    2012-01-01

    Gingival and Periodontal diseases represent a major concern both in dentistry and medicine. The majority of the contributing factors and causes in the etiology of these diseases are reduced or treated with ozone in all its application forms (gas, water, oil). The beneficial biological effects of ozone, its anti-microbial activity, oxidation of bio-molecules precursors and microbial toxins implicated in periodontal diseases and its healing and tissue regeneration properties, make the use of ozone well indicated in all stages of gingival and periodontal diseases. The primary objective of this article is to provide a general review about the clinical applications of ozone in periodontics. The secondary objective is to summarize the available in vitro and in vivo studies in Periodontics in which ozone has been used. This objective would be of importance to future researchers in terms of what has been tried and what the potentials are for the clinical application of ozone in Periodontics. PMID:22574088

  2. Unraveling the sources of ground level ozone in the Intermountain Western United States using Pb isotopes.

    PubMed

    Christensen, John N; Weiss-Penzias, Peter; Fine, Rebekka; McDade, Charles E; Trzepla, Krystyna; Brown, Shaun T; Gustin, Mae Sexauer

    2015-10-15

    Ozone as an atmospheric pollutant is largely produced by anthropogenic precursors and can significantly impact human and ecosystem health, and climate. The U.S. Environmental Protection Agency has recently proposed lowering the ozone standard from 75 ppbv (MDA8 = Maximum Daily 8-Hour Average) to between 65 and 70 ppbv. This will result in remote areas of the Intermountain West that includes many U.S. National Parks being out of compliance, despite a lack of significant local sources. We used Pb isotope fingerprinting and back-trajectory analysis to distinguish sources of imported ozone to Great Basin National Park in eastern Nevada. During discrete Chinese Pb events (> 1.1 ng/m(3) & > 80% Asian Pb) trans-Pacific transported ozone was 5 ± 5.5 ppbv above 19 year averages for those dates. In contrast, concentrations during regional transport from the Los Angeles and Las Vegas areas were 15 ± 2 ppbv above the long-term averages, and those characterized by high-altitude transport 3 days prior to sampling were 19 ± 4ppbv above. However, over the study period the contribution of trans-Pacific transported ozone increased at a rate of 0.8 ± 0.3 ppbv/year, suggesting that Asian inputs will exceed regional and high altitude sources by 2015-2020. All of these sources will impact regulatory compliance with a new ozone standard, given increasing global background.

  3. Tropospheric Ozone Changes

    NASA Astrophysics Data System (ADS)

    Oltmans, S. J.; Lefohn, A. S.; Scheel, H.; Brunke, E. G.; Claude, H.; Tarasick, D. W.; Galbally, I.; Bodeker, G.; Redondas, A.; Simmonds, P.; Koide, T.; Schmidlin, F. J.; Harris, J. M.; Johnson, B. J.; Davies, J.; Cuevas, E.; Meyer, C.; Shadwick, D.

    2008-12-01

    Growing recognition of the role of "background" tropospheric ozone on climate forcing and as a boundary condition for air quality changes highlights the importance of obtaining a broad picture of tropospheric ozone changes. Key surface and ozonesonde observing sites with tropospheric ozone measurement records longer than ~15 years have been selected to characterize longer term tropospheric ozone changes over broad geographic regions. The sites chosen vary from those with minimal impact by local ozone pollution sources to those that are in relatively close proximity to ozone precursor emissions and are thus affected in part by these sources. Consideration is given to the extent to which various time series represent broad geographic scales. Some series with more limited geographic representativeness can provide valuable information because of the length of the record, particularly in an underrepresented region. The vertical profile information from the ozonesonde stations, which have some of the longest tropospheric ozone records, provides a unique perspective on ozone in the free troposphere that is much less influenced by more local conditions. The general slowing or flattening of ozone increases seen at a number of locations beginning in the early 1990s has generally continued. At Naha, Japan there has been a significant increase in recent years that has not been seen at other Japanese ozonesonde locations. At high latitudes over North America a decade long decline in tropospheric ozone beginning in the 1980s has generally reversed with amounts now similar to those at the beginning of the record. In the S.H. several sites in the mid latitudes have shown significant increases. Although some overall patterns on changes emerge on regional scales and in some cases on continental scales, more general conclusions on hemispheric and global scales do not emerge. This is likely consistent with the varied pattern of ozone lifetimes, precursor emission changes, and

  4. The Antarctic ozone hole

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S.

    1988-01-01

    Processes that may be responsible for the thinning in the ozone layer above the South Pole are described. The chlorine catalytic cycle which destroys ozone is described, as are the major types of reactions that are believed to interfere with this cycle by forming chlorine reservoirs. The suspected contributions of polar stratospheric clouds to these processes are examined. Finally, the possibility that the ozone hole may be due more to a shift in atmospheric dynamics than to chemical destruction is addressed.

  5. Transatlantic transport of pollution and its effects on surface ozone in Europe and North America

    NASA Astrophysics Data System (ADS)

    Li, Qinbin; Jacob, Daniel J.; Bey, Isabelle; Palmer, Paul I.; Duncan, Bryan N.; Field, Brendan D.; Martin, Randall V.; Fiore, Arlene M.; Yantosca, Robert M.; Parrish, David D.; Simmonds, Peter G.; Oltmans, Samuel J.

    2002-07-01

    We examine the transatlantic transport of anthropogenic ozone and its impact on surface ozone in Europe and North America by using a 5-year (1993-1997) simulation with the GEOS-CHEM global three-dimensional model of tropospheric chemistry. Long-term time series of ozone and CO at Mace Head (Ireland) and Sable Island (Canada) are used to evaluate transatlantic transport in the model. North American anthropogenic emissions contribute on average 5 ppbv to surface ozone at Mace Head, and up to 10-20 ppbv during transatlantic transport events, which are forerunners of broader events in Europe. These events are associated with low-level westerly flow driven by an intense Icelandic low between Iceland and the British Isles. North American influence on ozone at Mace Head is strongly correlated with the North Atlantic Oscillation (NAO), implying that the NAO index can be used to forecast transatlantic transport of North American pollution to Europe. European anthropogenic emissions contribute on average less than 2 ppbv to surface ozone at Sable Island but up to 5-10 ppbv during transatlantic transport events. These events are associated with low-level easterly flow established by anomalous low pressure at 45°N over the North Atlantic. North American anthropogenic emissions enhance surface ozone in continental Europe by 2-4 ppbv on average in summer and by 5-10 ppbv during transatlantic transport events; transport in the boundary layer and subsidence from the free troposphere are both important mechanisms. We find in the model that 20% of the violations of the European Council ozone standard (55 ppbv, 8-hour average) in the summer of 1997 over Europe would not have occurred in the absence of anthropogenic emissions from North America. North American influence on surface ozone in Europe is particularly strong at the thresholds used for the European standards (55-65 ppbv).

  6. Modeling of Regional Climate Change Effects on Ground-Level Ozone and Childhood Asthma

    PubMed Central

    Sheffield, Perry E.; Knowlton, Kim; Carr, Jessie L.; Kinney, Patrick L.

    2011-01-01

    Background The adverse respiratory effects of ground-level ozone are well-established. Ozone is the air pollutant most consistently projected to increase under future climate change. Purpose To project future pediatric asthma emergency department visits associated with ground-level ozone changes, comparing 1990s to 2020s. Methods This study assessed future numbers of asthma emergency department visits for children aged 0–17 years using (1) baseline New York City metropolitan area emergency department rates, (2) a dose–response relationship between ozone levels and pediatric asthma emergency department visits, and (3) projected daily 8-hour maximum ozone concentrations for the 2020s as simulated by a global-to-regional climate change and atmospheric chemistry model. Sensitivity analyses included population projections and ozone precursor changes. This analysis occurred in 2010. Results In this model, climate change could cause an increase in regional summer ozone-related asthma emergency department visits for children aged 0–17 years of 7.3% across the New York City metropolitan region by the 2020s. This effect diminished with inclusion of ozone precursor changes. When population growth is included, the projections of morbidity related to ozone are even larger. Conclusions The results of this analysis demonstrate that the use of regional climate and atmospheric chemistry models make possible the projection of local climate change health effects for specific age groups and specific disease outcomes – such as emergency department visits for asthma. Efforts should be made to improve on this type of modeling to inform local and wider-scale climate change mitigation and adaptation policy. PMID:21855738

  7. SMM mesospheric ozone measurements

    NASA Technical Reports Server (NTRS)

    Aikin, A. C.

    1990-01-01

    The main objective was to understand the secular and seasonal behavior of ozone in the lower mesosphere, 50 to 70 km. This altitude region is important in understanding the factors which determine ozone behavior. A secondary objective is the study of stratospheric ozone in the polar regions. Use is made of results from the SBUV satellite borne instrument. In the Arctic the interaction between chlorine compounds and low molecular weight hydrocarbons is studied. More than 30,000 profiles were obtained using the UVSP instrument on the SMM spacecraft. Several orbits of ozone data per day were obtained allowing study of the current rise in solar activity from the minimum until the present. Analysis of Nimbus 7 SBUV data in Antarctic spring indicates that ozone is depleted within the polar vortex relative to ozone outside the vortex. This depletion confirms the picture of ozone loss at altitudes where polar stratospheric clouds exist. In addition, there is ozone loss above the cloud level indicating that there is another mechanism in addition to ozone loss initiated by heterogeneous chlorine reactions on cloud particles.

  8. A Holistic Evaluation of the Houston, Texas Ozone Attainment Episode

    NASA Astrophysics Data System (ADS)

    Biton, L.; Vizuete, W.; Kim, B.; Jeffries, H. E.

    2006-12-01

    In early 2006, the Texas Commission on Environmental Quality (TCEQ) released a simulation episode to form the basis for its 8-Hour Ozone State Implementation Plan (SIP). The SIP details steps to be taken to bring the Houston-Galveston-Brazoria region into attainment of the National Ambient Air Quality Standard for ozone (O3). The modeling episode will have significant impacts on regulatory decision-making, thus affecting the regional economy and human health. At present model performance evaluations (MPEs) are based on guidelines set by the Environmental Protection Agency (EPA) that rely heavily on statistical measures. While the episode falls within the recommended range for these EPA statistical metrics, examining the level of agreement between model predictions and observations for O3 is not a sufficient method to assess model accuracy. We have discovered severe inaccuracies in the 8-Hour modeling episode with an evaluation methodology that recognizes that (1) the formation of tropospheric O3 system is non-linear with respect to its precursors and (2) is the result of a multitude of chemical, emission, and meteorological processes. This paper presents the results of this improved evaluation method using new tools and software developed at the University of North Carolina at Chapel Hill. These tools were designed specifically to compensate for inadequacies in the existing statistical methods currently used for MPE. These tools enable investigators to review O3 production and concentrations in the context of meteorological and chemical conditions, allowing more holistic analytical techniques, not captured by traditional statistical metrics. In our analysis all modeling results are compared with high-resolution data from multiple sources, including an extensive ground-monitoring network, automatic gas-chromatographs (auto-GCs), and aircraft. First in our investigation, as a measure of progress, the latest 8-Hour episode is compared to TCEQ"s previous 1-Hour O3 SIP

  9. The Impact of Oil and Natural Gas Activity on Ozone Formation in the Colorado Front Range

    NASA Astrophysics Data System (ADS)

    Hornbrook, R. S.; Apel, E. C.; Hills, A. J.; Blake, D. R.; Blake, N. J.; Schroeder, J.; Fried, A.; Weibring, P.; Richter, D.; Walega, J.; Mauldin, L.; Cantrell, C. A.; Hall, S. R.; Ullmann, K.; Weinheimer, A. J.; Montzka, D.; Orlando, J. J.; Tyndall, G. S.; Campos, T. L.; Stell, M. H.; Heikes, B.; Treadaway, V.; O'Sullivan, D. W.; Huey, L. G.; Tanner, D.; Cohen, R. C.; Flocke, F. M.; Pfister, G.; Knote, C. J.; Emmons, L. K.

    2015-12-01

    The 2014 Front Range Air Pollution and Photochemistry Experiment (FRAPPE) was a ground-based and airborne field study designed to characterize and understand air quality in the Colorado Front Range, where National Ambient Air Quality Standards (NAAQS) ozone levels are frequently exceeded during summertime. A primary goal of the study was to determine the factors controlling surface ozone in the Front Range. As part of the project, measurements of many trace gases were observed on board the NSF/NCAR C-130 by a suite of instrumentation, including the NCAR Trace Organic Gas Analyzer (TOGA), which made measurements of a set of volatile organic compounds (VOCs). VOCs are crucial for characterizing emissions and photochemical processing in the Front Range, as well as the air transported into the region. During recent years, oil and natural gas (O&NG) activity in the Front Range has been growing rapidly. Ratios of observed aromatic hydrocarbons, butanes and pentanes demonstrate distinct fingerprinting that can be used to distinguish both between different types of O&NG activities and between O&NG extraction regions in the FRAPPE study region and beyond. Using the observed hydrocarbon data along with other trace gas observations, we will compare contributions of O&NG emissions to OH reactivities in different regions in the Front Range, and present box model results demonstrating the impact of O&NG activities on ozone formation.

  10. Ozone and temperature trends

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S.; Fioletov, Vitali; Bishop, Lane; Godin, Sophie; Bojkov, Rumen D.; Kirchhoff, Volker; Chanin, Marie-Lise; Zawodny, Joseph M.; Zerefos, Christos S.; Chu, William

    1991-01-01

    An update of the extensive reviews of the state of knowledge of measured ozone trends published in the Report of the International Ozone Trends Panel is presented. The update contains a review of progress since these reports, including reviewing of the ozone records, in most cases through March 1991. Also included are some new, unpublished reanalyses of these records including a complete reevaluation of 29 stations located in the former Soviet Union. The major new advance in knowledge of the measured ozone trend is the existence of independently calibrated satellite data records from the Total Ozone Mapping Spectrometer (TOMS) and Stratospheric Aerosol and Gas Experiment (SAG) instruments. These confirm many of the findings, originally derived from the Dobson record, concerning northern mid-latitude changes in ozone. We now have results from several instruments, whereas the previously reported changes were dependent on the calibration of a single instrument. This update will compare the ozone records from many different instruments to determine whether or not they provide a consistent picture of the ozone change that has occurred in the atmosphere. The update also briefly considers the problem of stratospheric temperature change. As in previous reports, this problem received significantly less attention, and the report is not nearly as complete. This area needs more attention in the future.

  11. Saving Our Ozone Shield.

    ERIC Educational Resources Information Center

    Lacoste, Beatrice

    1992-01-01

    Discusses the introduction and continued use of chlorofluorocarbons (CFCs) as related to stratospheric ozone depletion. Presents the characteristics of CFCs conducive to the chemical reaction with ozone, the history of CFC use and detection of related environmental problems, health hazards, and alternatives to CFC use. (MCO)

  12. Polar Ozone Workshop. Abstracts

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.

    1988-01-01

    Results of the proceedings of the Polar Ozone Workshop held in Snowmass, CO, on May 9 to 13, 1988 are given. Topics covered include ozone depletion, ozonometry, polar meteorology, polar stratospheric clouds, remote sensing of trace gases, atmospheric chemistry and dynamical simulations.

  13. The Antarctic Ozone Hole.

    ERIC Educational Resources Information Center

    Stolarski, Richard S.

    1988-01-01

    Discusses the Airborne Antarctic Ozone Experiment (1987) and the findings of the British Antarctic Survey (1985). Proposes two theories for the appearance of the hole in the ozone layer over Antarctica which appears each spring; air pollution and natural atmospheric shifts. Illustrates the mechanics of both. Supports worldwide chlorofluorocarbon…

  14. Observing trends in total ozone and extreme ozone events

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2014-05-01

    The ozone layer in the stratosphere has been recovering since the 1989 Montreal Protocol reduced the use of ozone-destroying chlorofluorocarbons. Fitzka et al. observed trends in total ozone levels and the vertical distribution of ozone at Hoher Sonnblick, a mountain in Austria, from 1994 to 2011.

  15. Investigation of the influence of transport from oil and natural gas regions on elevated ozone levels in the northern Colorado front range.

    PubMed

    Evans, Jason M; Helmig, Detlev

    2017-02-01

    The Northern Colorado Front Range (NCFR) has been in exceedance of the ozone National Ambient Air Quality Standard (NAAQS) since 2004, which has led to much debate over the sources of ozone precursors to the region, as this area is home to both the Denver, CO, metropolitan area and the Denver-Julesburg Basin, which has experienced rapid growth of oil and natural gas (O&NG) operations and associated emissions. Several recent studies have reported elevated levels of atmospheric volatile organic compounds (VOCs) as a result of O&NG emissions and the potential for significant ozone production from these emissions, despite implementation of stricter O&NG VOC emissions regulations in 2008. Approximately 88% of 1-hr elevated ozone events (>75 ppbv) occur during June-August, indicating that elevated ozone levels are driven by regional photochemistry. Analyses of surface ozone and wind observations from two sites, namely, South Boulder and the Boulder Atmospheric Observatory, both near Boulder, CO, show a preponderance of elevated ozone events associated with east-to-west airflow from regions with O&NG operations in the N-ESE, and a relatively minor contribution of transport from the Denver Metropolitan area to the SE-S. Transport from upwind areas associated with abundant O&NG operations accounts for on the order of 65% (mean for both sites) of 1-hr averaged elevated ozone levels, while the Denver urban corridor accounts for 9%. These correlations contribute to mounting evidence that air transport from areas with O&NG operation has a significant impact on ozone and air quality in the NCFR.

  16. The Hole in the Ozone Layer.

    ERIC Educational Resources Information Center

    Hamers, Jeanne S.; Jacob, Anthony T.

    This document contains information on the hole in the ozone layer. Topics discussed include properties of ozone, ozone in the atmosphere, chlorofluorocarbons, stratospheric ozone depletion, effects of ozone depletion on life, regulation of substances that deplete the ozone layer, alternatives to CFCs and Halons, and the future of the ozone layer.…

  17. The Two Faces of Ozone.

    ERIC Educational Resources Information Center

    Monastersky, Richard

    1989-01-01

    Provides answers to questions regarding the ozone problem: (1) nature of ozone in the troposphere and stratosphere; (2) possibility of sending the excess ozone at ground level to the stratosphere; (3) possibility of producing pure ozone and carrying it to the stratosphere; and (4) banning chlorofluorocarbons. (YP)

  18. Fundamentals of ISCO Using Ozone

    EPA Science Inventory

    In situ chemical oxidation (ISCO) using ozone involves the introduction of ozone gas (O3) into the subsurface to degrade organic contaminants of concern. Ozone is tri-molecular oxygen (O2) that is a gas under atmospheric conditions and is a strong oxidant. Ozone may react with ...

  19. Long-Term Ozone Exposure Attenuates 1-Nitronaphthalene–Induced Cytotoxicity in Nasal Mucosa

    PubMed Central

    Lee, Myong Gyong; Wheelock, Åsa M.; Boland, Bridget; Plopper, Charles G.

    2008-01-01

    1-Nitronaphthalene (1-NN) and ozone are cytotoxic air pollutants commonly found as components of photochemical smog. The mechanism of toxicity for 1-NN involves bioactivation by cytochrome P450s and subsequent adduction to proteins. Previous studies have shown that 1-NN toxicity in the lung is considerably higher in rats after long-term exposure to ozone compared with the corresponding filtered air–exposed control rats. The aim of the present study was to establish whether long-term exposure to ozone alters the susceptibility of nasal mucosa to the bioactivated toxicant, 1-NN. Adult male Sprague-Dawley rats were exposed to filtered air or 0.8 ppm ozone for 8 hours per day for 90 days, followed by a single treatment with 0, 12.5, or 50.0 mg/kg 1-NN by intraperitoneal injection. The results of the histopathologic analyses show that the nasal mucosa of rats is a target of systemic 1-NN, and that long-term ozone exposure markedly lessens the severity of injury, as well as the protein adduct formation by reactive 1-NN metabolites. The antagonistic effects were primarily seen in the nasal transitional epithelium, which corresponds to the main site of histologic changes attributed to ozone exposure (goblet cell metaplasia and hyperplasia). Long-term ozone exposure did not appear to alter susceptibility to 1-NN injury in other nasal regions. This study shows that long-term ozone exposure has a protective effect on the susceptibility of nasal transitional epithelium to subsequent 1-NN, a result that clearly contrasts with the synergistic toxicological effect observed in pulmonary airway epithelium in response to the same exposure regimen. PMID:17901409

  20. Information on the Interstate Transport Good Neighbor Provision for the 2012 Fine Particulate Matter (PM) National Ambient Air Quality Standards (NAAQS) under Clean Air Act (CAA) Section 110(a)(2)(D)(i)(I)

    EPA Pesticide Factsheets

    The purpose of this March 2016 memorandum is to provide information to EPA regional offices and states as they develop and review SIPs that address the interstate transport Good Neighbor provision as it pertains to the PM2.5 NAAQS

  1. Modeling ozone episodes in the Baltimore-Washington region

    NASA Technical Reports Server (NTRS)

    Ryan, William F.

    1994-01-01

    Surface ozone (O3) concentrations in excess of the National Ambient Air Quality Standard (NAAQS) continue to occur in metropolitan areas in the United States despite efforts to control emissions of O3 precursors. Future O3 control strategies will be based on results from modeling efforts that have just begun in many areas. Two initial questions that arise are model sensitivity to domain-specific conditions and the selection of episodes for model evaluation and control strategy development. For the Baltimore-Washington region (B-W), the presence of the Chesapeake Bay introduces a number of issues relevant to model sensitivity. In this paper, the specific questions of the determination of model volume (mixing height) for the Urban Airshed Model (UAM) is discussed and various alternative methods compared. For the latter question, several analytic approaches, Cluster Analysis and classification and Regression Tree (CART) analysis are undertaken to determine meteorological conditions associated with severe O3 events in the B-W domain.

  2. Ozone - plant surface reactions an important ozone loss term?

    NASA Astrophysics Data System (ADS)

    Hansel, Armin; Jud, Werner; Fischer, Lukas; Canaval, Eva; Wohlfahrt, Georg; Tissier, Alain

    2015-04-01

    Elevated tropospheric ozone concentrations are considered a toxic threat to plants responsible for global crop losses with associated economic costs of several billions dollar per year. Plant injuries have been related to the uptake of ozone through stomatal pores and oxidative effects damaging the internal leaf tissue. But a striking question remains: How much ozone enters the plant through open stomata and how much ozone is lost by chemical reactions at the plant surface? Until now surface losses are estimated from measured total ozone deposition fluxes and calculated stomatal conductance values. While stomatal conductance of CO2 and H2O is well understood and extensively used in describing plant atmosphere gas exchange, stomatal conductance of ozone is not well known. Here we use different Nicotiana tabacum varieties and find that surface reactions of ozone with diterpenoids synthesized by glandular trichomes reduce ozone flux through open stomata. Our measurements reveal that fast ozone loss at the plant surface is accompanied with prompt release of oxygenated volatile compounds. In the ozone fumigation experiments of different Nicotiana tabacum varieties the release of specific volatile oxy-VOCs allowed to identify the semi volatile precursor compounds at the plant surface. Ozone fumigation experiments with Norway spruce (Picea abies) and Scots Pine (Pinus sylvestris), two common species in the Northern Hemisphere, show also a significant ozone loss at the plant surface for Picea abies. Fluid dynamic calculations of ozone transport in the diffusive leaf boundary layer reveal a vertical but no horizontal ozone gradient thus reducing ozone fluxes through the pores in case of efficient ozone scavenging plant surfaces. We explain this efficient ozone protection mechanism by the porous surface architecture of plants in combination with unsaturated semi-volatile compounds deposited at the plant surface. These results show that unsaturated semi-volatile compounds at

  3. Who is More Affected by Ozone Pollution? A Systematic Review and Meta-Analysis

    PubMed Central

    Bell, Michelle L.; Zanobetti, Antonella; Dominici, Francesca

    2014-01-01

    Ozone is associated with adverse health; however, less is known about vulnerable/sensitive populations, which we refer to as sensitive populations. We systematically reviewed epidemiologic evidence (1988–2013) regarding sensitivity to mortality or hospital admission from short-term ozone exposure. We performed meta-analysis for overall associations by age and sex; assessed publication bias; and qualitatively assessed sensitivity to socioeconomic indicators, race/ethnicity, and air conditioning. The search identified 2,091 unique papers, with 167 meeting inclusion criteria (73 on mortality and 96 on hospitalizations and emergency department visits, including 2 examining both mortality and hospitalizations). The strongest evidence for ozone sensitivity was for age. Per 10-parts per billion increase in daily 8-hour ozone concentration, mortality risk for younger persons, at 0.60% (95% confidence interval (CI): 0.40, 0.80), was statistically lower than that for older persons, at 1.27% (95% CI: 0.76, 1.78). Findings adjusted for publication bias were similar. Limited/suggestive evidence was found for higher associations among women; mortality risks were 0.39% (95% CI: −0.22, 1.00) higher than those for men. We identified strong evidence for higher associations with unemployment or lower occupational status and weak evidence of sensitivity for racial/ethnic minorities and persons with low education, in poverty, or without central air conditioning. Findings show that some populations, especially the elderly, are particularly sensitive to short-term ozone exposure. PMID:24872350

  4. Surface ozone background in the United States: Canadian and Mexican pollution influences

    NASA Astrophysics Data System (ADS)

    Wang, Huiqun; Jacob, Daniel J.; Le Sager, Philippe; Streets, David G.; Park, Rokjin J.; Gilliland, Alice B.; van Donkelaar, A.

    We use a global chemical transport model (GEOS-Chem) with 1° × 1° horizontal resolution to quantify the effects of anthropogenic emissions from Canada, Mexico, and outside North America on daily maximum 8-hour average ozone concentrations in US surface air. Simulations for summer 2001 indicate mean North American and US background concentrations of 26 ± 8 ppb and 30 ± 8 ppb, as obtained by eliminating anthropogenic emissions in North America vs. in the US only. The US background never exceeds 60 ppb in the model. The Canadian and Mexican pollution enhancement averages 3 ± 4 ppb in the US in summer but can be occasionally much higher in downwind regions of the northeast and southwest, peaking at 33 ppb in upstate New York (on a day with 75 ppb total ozone) and 18 ppb in southern California (on a day with 68 ppb total ozone). The model is successful in reproducing the observed variability of ozone in these regions, including the occurrence and magnitude of high-ozone episodes influenced by transboundary pollution. We find that exceedances of the 75 ppb US air quality standard in eastern Michigan, western New York, New Jersey, and southern California are often associated with Canadian and Mexican pollution enhancements in excess of 10 ppb. Sensitivity simulations with 2020 emission projections suggest that Canadian pollution influence in the Northeast US will become comparable in magnitude to that from domestic power plants.

  5. Stratospheric ozone depletion

    PubMed Central

    Rowland, F. Sherwood

    2006-01-01

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290–320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime—the ‘Antarctic ozone hole’. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  6. Stratospheric ozone depletion.

    PubMed

    Rowland, F Sherwood

    2006-05-29

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290-320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime-the 'Antarctic ozone hole'. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules.

  7. Ozone and NOx chemistry in the eastern US: evaluation of CMAQ/CB05 with satellite (OMI) data

    NASA Astrophysics Data System (ADS)

    Canty, T. P.; Hembeck, L.; Vinciguerra, T. P.; Anderson, D. C.; Goldberg, D. L.; Carpenter, S. F.; Allen, D. J.; Loughner, C. P.; Salawitch, R. J.; Dickerson, R. R.

    2015-02-01

    Regulatory air quality models, such as the Community Multiscale Air Quality model (CMAQ), are used by federal and state agencies to guide policy decisions that determine how to best achieve adherence with National Ambient Air Quality Standards for surface ozone. We use observations of ozone and its important precursor NO2 to test the representation of the photochemistry and emission of ozone precursors within CMAQ. Observations of tropospheric column NO2 from the Ozone Monitoring Instrument (OMI), retrieved by two independent groups, show that the model overestimates urban NO2 and underestimates rural NO2 under all conditions examined for July and August 2011 in the US Northeast. The overestimate of the urban to rural ratio of tropospheric column NO2 for this baseline run of CMAQ (CB05 mechanism, mobile NOx emissions from the National Emissions Inventory; isoprene emissions from MEGAN v2.04) suggests this model may under estimate the importance of interstate transport of NOx. This CMAQ simulation leads to a considerable overestimate of the 2 month average of 8 h daily maximum surface ozone in the US Northeast, as well as an overestimate of 8 h ozone at AQS sites during days when the state of Maryland experienced NAAQS exceedances. We have implemented three changes within CMAQ motivated by OMI NO2 as well as aircraft observations obtained in July 2011 during the NASA DISCOVER-AQ campaign: (a) the modeled lifetime of organic nitrates within CB05 has been reduced by a factor of 10, (b) emissions of NOx from mobile sources has been reduced by a factor of 2, and (c) isoprene emissions have been reduced by using MEGAN v2.10 rather than v2.04. Compared to the baseline simulation, the CMAQ run using all three of these changes leads to a considerably better simulation of the ratio of urban to rural column NO2, better agreement with the 2 month average of daily 8 h maximum ozone in the US Northeast, fewer number of false positives of an ozone exceedance throughout the domain

  8. Ozone and NOx chemistry in the eastern US: evaluation of CMAQ/CB05 with satellite (OMI) data

    NASA Astrophysics Data System (ADS)

    Canty, T. P.; Hembeck, L.; Vinciguerra, T. P.; Anderson, D. C.; Goldberg, D. L.; Carpenter, S. F.; Allen, D. J.; Loughner, C. P.; Salawitch, R. J.; Dickerson, R. R.

    2015-10-01

    Regulatory air quality models, such as the Community Multiscale Air Quality model (CMAQ), are used by federal and state agencies to guide policy decisions that determine how to best achieve adherence with National Ambient Air Quality Standards for surface ozone. We use observations of ozone and its important precursor NO2 to test the representation of the photochemistry and emission of ozone precursors within CMAQ. Observations of tropospheric column NO2 from the Ozone Monitoring Instrument (OMI), retrieved by two independent groups, show that the model overestimates urban NO2 and underestimates rural NO2 under all conditions examined for July and August 2011 in the US Northeast. The overestimate of the urban to rural ratio of tropospheric column NO2 for this baseline run of CMAQ (CB05 mechanism, mobile NOx emissions from the National Emissions Inventory; isoprene emissions from MEGAN v2.04) suggests this model may underestimate the importance of interstate transport of NOx. This CMAQ simulation leads to a considerable overestimate of the 2-month average of 8 h daily maximum surface ozone in the US Northeast, as well as an overestimate of 8 h ozone at AQS sites during days when the state of Maryland experienced NAAQS exceedances. We have implemented three changes within CMAQ motivated by OMI NO2 as well as aircraft observations obtained in July 2011 during the NASA DISCOVER-AQ campaign: (a) the modeled lifetime of organic nitrates within CB05 has been reduced by a factor of 10, (b) emissions of NOx from mobile sources has been reduced by a factor of 2, and (c) isoprene emissions have been reduced by using MEGAN v2.10 rather than v2.04. Compared to the baseline simulation, the CMAQ run using all three of these changes leads to considerably better simulation of column NO2 in both urban and rural areas, better agreement with the 2-month average of daily 8 h maximum ozone in the US Northeast, fewer number of false positives of an ozone exceedance throughout the domain

  9. Ozone Profiles and Tropospheric Ozone from Global Ozone Monitoring Experiment

    NASA Technical Reports Server (NTRS)

    Liu, X.; Chance, K.; Sioris, C. E.; Sparr, R. J. D.; Kuregm, T. P.; Martin, R. V.; Newchurch, M. J.; Bhartia, P. K.

    2003-01-01

    Ozone profiles are derived from backscattered radiances in the ultraviolet spectra (290-340 nm) measured by the nadir-viewing Global Ozone Monitoring Experiment using optimal estimation. Tropospheric O3 is directly retrieved with the tropopause as one of the retrieval levels. To optimize the retrieval and improve the fitting precision needed for tropospheric O3, we perform extensive wavelength and radiometric calibrations and improve forward model inputs. Retrieved O3 profiles and tropospheric O3 agree well with coincident ozonesonde measurements, and the integrated total O3 agrees very well with Earth Probe TOMS and Dobson/Brewer total O3. The global distribution of tropospheric O3 clearly shows the influences of biomass burning, convection, and air pollution, and is generally consistent with our current understanding.

  10. Polar Ozone Losses

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Bhartia, P. K. (Technical Monitor)

    2001-01-01

    Since the discovery of the Antarctic ozone hole, a great deal of attention has been focused on the polar regions to both identify the chemistry and physics of the large losses, and to provide an understanding of the future of polar ozone. In this review talk, I will discuss the secular trends of ozone in both the Antarctic and Arctic regions, and I will review some of the principal research results of the last few years. In particular, I will emphasize some of the results from the SOLVE-THESEO 2000 campaign that occurred over the course of the winter of 1999-2000.

  11. 76 FR 38997 - Approval and Promulgation of Implementation Plans; State of Oregon; Regional Haze State...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-05

    ...EPA is approving portions of a State Implementation Plan (SIP) revision submitted by the State of Oregon on December 20, 2010, as meeting the requirements of Clean Air Act (CAA) section 110(a)(2)(D)(i)(II) as it applies to visibility for the 1997 8-hour ozone and 1997 particulate matter (PM2.5) National Ambient Air Quality Standards (NAAQS). EPA is also approving portions of the......

  12. 40 CFR 51.1103 - Application of classification and attainment date provisions in CAA section 181 of subpart 2 to...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). 51.1103 Section... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). (a) In... Ozone NAAQS (0.075 ppm) for Areas Subject to Section 51.1102(a) Area class 8-hour design value(ppm...

  13. 40 CFR 51.1103 - Application of classification and attainment date provisions in CAA section 181 of subpart 2 to...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). 51.1103 Section... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). (a) In... Ozone NAAQS (0.075 ppm) for Areas Subject to Section 51.1102(a) Area class 8-hour design value(ppm...

  14. 40 CFR 51.1103 - Application of classification and attainment date provisions in CAA section 181 of subpart 2 to...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). 51.1103 Section... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). (a) In... Ozone NAAQS (0.075 ppm) for Areas Subject to Section 51.1102(a) Area class 8-hour design value(ppm...

  15. Final Environmental Assessment Addressing Building Demolition at Kirtland Air Force Base, New Mexico

    DTIC Science & Technology

    2010-04-01

    DATE APR 2010 2. REPORT TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND SUBTITLE Final Environmental Assessment Addressing Building...prepared. This analysis fulfills the requirements ofNEPA and the CEQ Regulations. Date Signature on f ile, Signed 12 April 2010 MICHAELS. DUVALL...after the effective date of the designation of that area for the 8-hour ozone NAAQS. The effective designation date for most areas was June 15, 2004

  16. 76 FR 41088 - Approval and Promulgation of Implementation Plans; Kentucky; 110(a)(1) and (2) Infrastructure...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ...EPA is taking final action to approve the December 13, 2007, submission by the Commonwealth of Kentucky, through the Kentucky Division of Air Quality (KDAQ) as demonstrating that the Commonwealth meets the state implementation plan (SIP) requirements of sections 110(a)(1) and (2) of the Clean Air Act (CAA or the Act) for the 1997 8- hour ozone national ambient air quality standards (NAAQS).......

  17. 76 FR 41100 - Approval and Promulgation of Implementation Plans; Alabama; 110(a)(1) and (2) Infrastructure...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ...EPA is taking final action to approve the December 10, 2007, submission by the State of Alabama, through the Alabama Department of Environmental Management (ADEM) as demonstrating that the State meets the state implementation plan (SIP) requirements of sections 110(a)(1) and (2) of the Clean Air Act (CAA or the Act) for the 1997 8-hour ozone national ambient air quality standards (NAAQS).......

  18. The Impact of Meteorology on Ozone Levels in the Lake Tahoe Basin

    NASA Astrophysics Data System (ADS)

    Theiss, Sandra

    The Lake Tahoe Basin is located on the California-Nevada border and occasionally experiences elevated levels of ozone exceeding the 70 ppb California Air Resources Board (CARB) ambient air quality standard (8-hour average). Previous studies indicate that both the local generation of ozone in the Basin and long-range transport from out-of-Basin sources are important in contributing to ozone exceedances, but little is known about the impact of meteorology on the distribution of ozone source regions. In order to develop a better understanding of the factors affecting ozone levels and sources in the Lake Tahoe Basin, this study combines observational data from a 2010 and 2012 summer field campaigns, HYSPLIT back trajectories, and WRF model output to examine the meteorological influences of ozone transport in the topographically complex Lake Tahoe Basin. Findings from the field work portions of this study include enhanced background ozone levels at higher elevations, the local circulation pattern of lake breezes occurring at Lake level sites, and an indication that ozone precursors are coming off the Lake. Our analysis also showed that if transport of ozone does occur, it is more likely to come from the San Joaquin Valley to the south rather than originate in the large cities to the west, such as Sacramento and San Francisco. Analysis of modeled PBL schemes as compared with observational data showed that the ACM2 PBL scheme best represented the geographical domain. The ACM2 PBL scheme was then used to show wind circulation patterns in the Lake Tahoe Basin and concluded that there is decent vertical mixing over the Basin and no indication of ozone transport from the west however some indication of transport from the east. Overall this study concludes that transport from the west is less significant than transport from the south and east, and that transport only influences ozone values at higher elevations. Within the Basin itself (at lower elevations), local factors

  19. Ozone Therapy in Dentistry

    PubMed Central

    Domb, William C

    2014-01-01

    Summary The 21st century dental practice is quite dynamic. New treatment protocols and new materials are being developed at a rapid pace. Ozone dental therapy falls into the category of new treatment protocols in dentistry, yet ozone is not new at all. Ozone therapy is already a major treatment modality in Europe, South America and a number of other countries. What is provided here will not be an exhaustive scientific treatise so much as a brief general introduction into what dentists are now doing with ozone therapies and the numerous oral/systemic links that make this subject so important for physicians so that, ultimately, they may serve their patients more effectively and productively. PMID:25363268

  20. Addressing Ozone Layer Depletion

    EPA Pesticide Factsheets

    Access information on EPA's efforts to address ozone layer depletion through regulations, collaborations with stakeholders, international treaties, partnerships with the private sector, and enforcement actions under Title VI of the Clean Air Act.

  1. Ozone Correlative Measurements Workshop

    NASA Technical Reports Server (NTRS)

    Hilsenrath, E. (Editor)

    1985-01-01

    A study was conducted to determine the necessary parameters for the correlation of data on Earth ozone. Topics considered were: (1) measurement accuracy; (2) equipment considerations (SBUV); and (3) ground based measurements to support satellite data.

  2. Chronic lung injury risk estimates for urban areas having ozone patterns similar to those in the Northeast

    SciTech Connect

    Absil, M.; Narducci, P.; Whitfield, R.; Richmond, H.M.

    1991-12-31

    This paper describes the approach and result of an assessment of health risks associated with long-term exposure to ozone. The health endpoint of interest is the probability of formation of mild lesions in the centriacinar region of the lung among children living in New York City. The risk model incorporates an exposure model and a health model. The exposure model is preliminary results of the probabilistic NAAQS Exposure Model (P-NEM) for ozone, and the health model is the judgments of active researchers about the likelihood of formation of ozone-induced lesions in the human lung. Children and New York City were chosen as the population and city of interest because it is believed that children are more sensitive to ozone than any other group of people, and New York City is more representative of other urban areas than Los Angeles, the other city of which P-NEM exposure results are available. Risk results are presented for ten exposure distributions generated by P-NEM, two air quality scenarios (``as-is`` and ``attainment``), and two exposure periods (1 and 10 ozone seasons). The results vary across experts, are not very sensitive to variations in P-NEM exposure distributions, are lower for attainment conditions than as-is conditions, and are lower for 1 season of exposure than 10 seasons. Although these results are specific to children living in areas having exposure patterns similar to those found in the Northeast, they are fairly representative of results for outdoor workers in the Northeast and Southern California and for children in Southern California. The reason for this is that many experts believe that children and outdoor workers respond in a similar fashion to the given exposure patterns, or that exposure patterns in the Northeast and Southern California are similar. Some experts held both of these beliefs. These results should help policymakers evaluate alternative national ambient air quality standards for ozone. 4 refs., 9 figs., 3 tabs.

  3. Chronic lung injury risk estimates for urban areas having ozone patterns similar to those in the Northeast

    SciTech Connect

    Absil, M.; Narducci, P.; Whitfield, R. ); Richmond, H.M. . Office of Air Quality Planning and Standards)

    1991-01-01

    This paper describes the approach and result of an assessment of health risks associated with long-term exposure to ozone. The health endpoint of interest is the probability of formation of mild lesions in the centriacinar region of the lung among children living in New York City. The risk model incorporates an exposure model and a health model. The exposure model is preliminary results of the probabilistic NAAQS Exposure Model (P-NEM) for ozone, and the health model is the judgments of active researchers about the likelihood of formation of ozone-induced lesions in the human lung. Children and New York City were chosen as the population and city of interest because it is believed that children are more sensitive to ozone than any other group of people, and New York City is more representative of other urban areas than Los Angeles, the other city of which P-NEM exposure results are available. Risk results are presented for ten exposure distributions generated by P-NEM, two air quality scenarios ( as-is'' and attainment''), and two exposure periods (1 and 10 ozone seasons). The results vary across experts, are not very sensitive to variations in P-NEM exposure distributions, are lower for attainment conditions than as-is conditions, and are lower for 1 season of exposure than 10 seasons. Although these results are specific to children living in areas having exposure patterns similar to those found in the Northeast, they are fairly representative of results for outdoor workers in the Northeast and Southern California and for children in Southern California. The reason for this is that many experts believe that children and outdoor workers respond in a similar fashion to the given exposure patterns, or that exposure patterns in the Northeast and Southern California are similar. Some experts held both of these beliefs. These results should help policymakers evaluate alternative national ambient air quality standards for ozone. 4 refs., 9 figs., 3 tabs.

  4. Stratospheric ozone is decreasing

    NASA Astrophysics Data System (ADS)

    Kerr, Richard A.

    1988-03-01

    The recent discovery that chlorofluorocarbons create the Antarctic ozone hole every October through reactions mediated by ice particles formed at the lowest temperatures of the stratosphere is discussed. A large-scale reanalysis of measurements reveals that protective stratospheric ozone has decreased during the past 17 yrs with some decreases greatly exceeding predictions. It is noted that standard models did not, and still do not, include the ice in their reaction schemes. A tendency toward larger losses at higher colder latitudes is seen.

  5. The ozone backlash

    SciTech Connect

    Taubes, G.

    1993-06-11

    While evidence for the role of chlorofluorocarbons in ozone depletion grows stronger, researchers have recently been subjected to vocal public criticism of their theories-and their motives. Their understanding of the mechanisms of ozone destruction-especially the annual ozone hole that appears in the Antarctic-has grown stronger, yet everywhere they go these days, they seem to be confronted by critics attacking their theories as baseless. For instance, Rush Limbaugh, the conservative political talk-show host and now-best-selling author of The Way Things Ought to Be, regularly insists that the theory of ozone depletion by CFCs is a hoax: bladerdash and poppycock. Zoologist Dixy Lee Ray, former governor of the state of Washington and former head of the Atomic Energy Commission, makes the same argument in her book, Trashing the Planet. The Wall Street Journal and National Review have run commentaries by S. Fred Singer, a former chief scientists for the Department of Transportation, purporting to shoot holes in the theory of ozone depletion. Even the June issue of Omni, a magazine with a circulation of more than 1 million that publishes a mixture of science and science fiction, printed a feature article claiming to expose ozone research as a politically motivated scam.

  6. Leaf gas exchange along a light graident in a sugar maple forest canopy experimentally exposed to ozone pollution

    SciTech Connect

    Tjoelker, M.G.; Volin, J.C.; Oleksyn, J.; Reich, P.B. )

    1993-06-01

    The impact of ozone on leaf gas exchange in a forest canopy as influenced by light environment was studied in a 35-year-old stand of sugar maple (Acer sacchharum) in southern Wisconsin. We developed a chamberless system to expose branches to elevated concentrations of ozone. Ten branches and ten paired controls in the upper canopy (14 to 16 m) were selected along a light gradient, ranging from sunlit (14.5 mol m[sup [minus]2] day[sup [minus]1] PPFD) to deeply shaded (0.6 mol m[sup [minus]2] day[sup [minus]1] PPFD). The branches were exposed for 8 hours each day to ozone concentrations averaging 95 nl 1[sup [minus]1](+/-13 SD), about twice the ambient levels between June and September. Among the branches, area-based rates of light-saturated photosynthesis and dark respiration were positively correlated with mean daily integrated PPFD. Light-saturated rates of photosynthesis and chlorophyll concentrations declined while dark respiration increased with increasing ozone dose. Over time stomatal conductance became uncoupled from light-saturated photosynthesis rates in exposed branches. Photosynthesis and quantum yield were reduced more in a shaded branch than in a sunlit branch in response to ozone treatment. In general, shaded branches were more sensitive to ozone than sunlit branches.

  7. A 15-Year Analysis of Surface Ozone Pollution in the Context of Hot Spells Episodes over Poland

    NASA Astrophysics Data System (ADS)

    Struzewska, Joanna; Jefimow, Maciej

    2016-10-01

    Analysis of summertime temperature characteristics and ozone exposure indexes were carried out for eight locations in Poland for a 15-year period (1997-2011). The number of days with the maximum temperature exceeding 25°C and 30°C was calculated for each year. The analysis covered the 8-hour running average and daily maximum of near surface ozone concentrations. Also, the accumulated exposure when ozone concentrations were above 120 μg/m3 (AOT60) was calculated as a diagnostic indicator of adverse health effects for each year. Although high ozone concentrations are associated with hot temperatures, the exposure to values higher than 120 μg /m3 is correlated with the length of the hot weather period rather than with the occurrence of days with extremely high temperatures. In most cases the elevated ozone concentrations occurred during days when the maximum temperature was higher than 24°C. Episodes of very high ozone concentrations, exceeding 180 μg /m3, were not associated with heat wave periods at analysed locations.

  8. Investigating ambient ozone formation regimes in neighboring cities of shale plays in the Northeast United States using photochemical modeling and satellite retrievals

    NASA Astrophysics Data System (ADS)

    Chang, Chih-Yuan; Faust, Eric; Hou, Xiangting; Lee, Pius; Kim, Hyun Cheol; Hedquist, Brent C.; Liao, Kuo-Jen

    2016-10-01

    This study investigates long-term (i.e., 2007-2014) fluctuations in ambient ozone formation regimes for cities adjacent to shale plays in the Northeast United States (U.S.). Ozone air quality in many cities of the Northeast U.S. does not meet the U.S. National Ambient Air Quality Standards (NAAQS), and understanding ambient ozone formation regimes is essential to develop effective air pollution mitigation strategies for cities violating the air quality standards. Since 2013, the U.S. has become the world's largest producer of tight oil and natural gas from shale rock, and previous studies show that emissions of air pollutant precursors from shale oil and gas-related activities would have the potential to affect ambient ozone air quality in adjacent cities of shale plays. This work leveraged (1) satellite-retrieved column densities of formaldehyde (HCHO) and nitrogen dioxide (NO2) from multiple instruments (i.e., Ozone Monitoring Instrument (OMI) and Global Ozone Monitoring Experiment-2 (GOME-2)); (2) photochemical air quality modeling and sensitivity analysis; and (3) ratios of satellite-retrieved air pollutant column densities to investigate ambient ozone formation regimes in neighboring cities of shale plays (i.e., Marcellus Shale) in the Northeast U.S. from 2007 to 2014. Our results show that ambient ozone formation in Boston, Pittsburgh, Philadelphia and Washington, D.C. (which are close to Marcellus Shale) was in the NOx -limited or transition regime during the period of study. Ambient ozone formation in New York City was in the transition regime during 2010-2013 and VOC -limited regime during 2007-2009 and in 2014. Based on the result of this study, we conclude that controls NOx emissions would mitigate ozone air pollution from 2007 to 2014 in most of the cities examined in this study. Controls of local VOC emissions would ease ozone air pollution in New York City during the study period. With projected increases in oil and gas production from shale plays in

  9. The Impact of Emission and Climate Change on Ozone in the United States under Representative Concentration Pathways (RCPs)

    SciTech Connect

    Gao, Yang; Fu, Joshua S.; Drake, John B.; Lamarque, J.-F.; Liu, Yang

    2013-09-27

    Dynamical downscaling was applied in this study to link the global climate-chemistry model Community Atmosphere Model (CAM-Chem) with the regional models: Weather Research and Forecasting (WRF) Model and Community Multi-scale Air Quality (CMAQ). Two Representative Concentration Pathway (RCP) scenarios (RCP 4.5 and RCP 8.5) were used to evaluate the climate impact on ozone concentrations in 2050s. Ozone concentrations in the lower-mid troposphere (surface to ~300 hPa), from mid- to high latitudes in the Northern Hemisphere (NH), show decreasing trends in RCP 4.5 between 2000s and 2050s, with the largest decrease of 4-10 ppbv occurring in the summer and the fall; and increasing trends (2-12 ppbv) in RCP 8.5 resulting from the increased methane emissions. In RCP 8.5, methane emissions increase by ~60% by the end of 2050s, accounting for more than 90% of ozone increases in summer and fall, and 60-80% in spring and winter. Under the RCP 4.5 scenario, in the summer when photochemical reactions are the most active, the large ozone precursor emissions reduction leads to the greatest decrease of downscaled surface ozone concentrations, ranging from 6 to 10 ppbv. However, a few major cities show ozone increases of 3 to 7 ppbv due to weakened NO titration. Under the RCP 8.5 scenario, in winter, downscaled ozone concentrations increase across nearly the entire continental US in winter, ranging from 3 to 10 ppbv due to increased methane emissions and enhanced stratosphere-troposphere exchange (STE). More intense heat waves are projected to occur by the end of 2050s in RCP 8.5, leading to more than 8 ppbv of the maximum daily 8-hour daily average (MDA8) ozone during the heat wave days than other days; this indicates the dramatic impact heat waves exert on high frequency ozone events.

  10. The Ozone Problem | Ground-level Ozone | New England | US ...

    EPA Pesticide Factsheets

    2017-04-10

    Many factors impact ground-level ozone development, including temperature, wind speed and direction, time of day, and driving patterns. Due to its dependence on weather conditions, ozone is typically a summertime pollutant and a chief component of summertime smog.

  11. Recovery of the Ozone Layer: The Ozone Depleting Gas Index

    NASA Astrophysics Data System (ADS)

    Hofmann, David J.; Montzka, Stephen A.

    2009-01-01

    The stratospheric ozone layer, through absorption of solar ultraviolet radiation, protects all biological systems on Earth. In response to concerns over the depletion of the global ozone layer, the U.S. Clean Air Act as amended in 1990 mandates that NASA and NOAA monitor stratospheric ozone and ozone-depleting substances. This information is critical for assessing whether the Montreal Protocol on Substances That Deplete the Ozone Layer, an international treaty that entered into force in 1989 to protect the ozone layer, is having its intended effect of mitigating increases in harmful ultraviolet radiation. To provide the information necessary to satisfy this congressional mandate, both NASA and NOAA have instituted and maintained global monitoring programs to keep track of ozone-depleting gases as well as ozone itself. While data collected for the past 30 years have been used extensively in international assessments of ozone layer depletion science, the language of scientists often eludes the average citizen who has a considerable interest in the health of Earth's protective ultraviolet radiation shield. Are the ozone-destroying chemicals declining in the atmosphere? When will these chemicals decline to pre-ozone hole levels so that the Antarctic ozone hole might disappear? Will this timing be different in the stratosphere above midlatitudes?

  12. Children's Models of the Ozone Layer and Ozone Depletion.

    ERIC Educational Resources Information Center

    Christidou, Vasilia; Koulaidis, Vasilis

    1996-01-01

    The views of 40 primary students on ozone and its depletion were recorded through individual, semi-structured interviews. The data analysis resulted in the formation of a limited number of models concerning the distribution and role of ozone in the atmosphere, the depletion process, and the consequences of ozone depletion. Identifies five target…

  13. CONTRIBUTION TO INDOOR OZONE LEVELS OF AN OZONE GENERATOR

    EPA Science Inventory

    This report gives results of a study of a commonly used commercially available ozone generator, undertaken to determine its impact on indoor ozone levels. xperiment were conducted in a typical mechanically ventilated office and in a test house. he generated ozone and the in-room ...

  14. Achievements in Stratospheric Ozone Protection

    EPA Pesticide Factsheets

    This report describes achievements in protecting the ozone layer, the benefits of these achievements, and strategies involved (e.g., using alternatives to ozone-depleting substances, phasing out harmful substances, and creating partnerships).

  15. Air Quality Guide for Ozone

    MedlinePlus

    Local Air Quality Conditions Zip Code: State : My Current Location Air Quality Guide for Ozone Ground-level ozone is one ... exposure and protect your health. For your local air quality, visit www.airnow.gov View or print guide ...

  16. Ozone Minimums, 1979 to 2013

    NASA Video Gallery

    Minimum concentration of ozone in the southern hemisphere for each year from 1979-2013 (there is no data from 1995). Each image is the day of the year with the lowest concentration of ozone. A grap...

  17. Health Effects of Ozone Pollution

    EPA Pesticide Factsheets

    Inhaling ozone can cause coughing, shortness of breath, worse asthma or bronchitis symptoms, and irritation and damage to airways.You can reduce your exposure to ozone pollution by checking air quality where you live.

  18. "OZONE SOURCE APPORTIONMENT IN CMAQ'

    EPA Science Inventory

    Ozone source attribution has been used to support various policy purposes including interstate transport (Cross State Air Pollution Rule) by U.S. EPA and ozone nonattainment area designations by State agencies. Common scientific applications include tracking intercontinental tran...

  19. An Inter-Regional Comparison of Ozone Sensitivity to Reductions in Emissions in Central California

    NASA Astrophysics Data System (ADS)

    Soong, S.; Tanrikulu, S.; Tran, C.; Jia, Y.; Beaver, S.; Matsuoka, J.; Cordova, J.

    2011-12-01

    Emissions of ozone precursors NOx and VOC have declined significantly in central California over the past 60 years due to rigorous emission control programs, with 40 to 50 percent reductions achieved from 1990 to 2010 alone. Three major air basins, however, are still designated as nonattainment areas for the federal 8-hour ozone standard: the San Francisco Bay Area (SFBA), Sacramento area and the San Joaquin Valley (SJV). Historically, ozone response to reductions in emissions varied from region to region. While the maximum hourly ozone concentrations have declined significantly in all three air basins, the locations of maximum ozone shifted. Some exceedance areas came into compliance with the standard while new areas started exceeding the standard. Some areas did not significantly respond to reductions in emissions. To meet the current ozone standard, additional emission reductions are needed. Further emission reductions above and beyond the goal of meeting the current standard will be needed if the EPA lowers the current standard. In an effort to help planners and decision makers, we have been conducting a modeling study to better understand how ozone may respond to future emission reductions in the region. In this initial phase of the study, we used the WRF-CMAQ modeling system to simulate ozone for July 12-28, 2006, a representative high ozone period for all three air basins. With the selected high grid resolution and optimum model setup, the model performance for the base case simulation was exceptionally good. Statistical agreement with observations was better than most previously applied models in the region. We performed a number of sensitivity simulations by reducing anthropogenic VOC or NOx emissions separately or together 10-60 percent at 10 percent intervals uniformly across the board and prepared EKMA diagrams at observation stations. We found that a 60 percent reduction in VOC and NOx emissions reduced the maximum ozone by 20-30 percent in the

  20. Production of NOx and other precursors of ozone formation in the Uinta Basin

    NASA Astrophysics Data System (ADS)

    Smith, E.; Lyman, S. N.; Martin, R. S.; Anderson, R.

    2012-12-01

    The Uinta Basin, located in northeastern Utah, sometimes experiences ozone mixing ratios greater than the EPA NAAQS during specific meteorological conditions that include a combination of snow cover and inversion. We monitored ozone and some of its precursors, including NO, NO2, NOx (NO + NO2), and NOy (sum of reactive nitrogen species), at two sites (Roosevelt and Horse Pool). The Roosevelt site is in a city of about 6,000 people, and the Horse Pool site is in an area of intensive oil and gas production. In February and March 2012, NO, NO2, and NOy mixing ratios were 0.5 ± 0.8, 5.2 ± 2.6, and 6.5 ± 3.9 ppb at Roosevelt and 0 ± 1.3, 2.8 ± 2.7, and 4.1 ± 4.4 ppb at Horse Pool, respectively (mean ± standard deviation). NO, NO2, and NOx were measured at 7 other sites around the Basin by other entities. The spatial and temporal patterns in NOx and NOy indicate the dominance of local source influences on observed mixing ratios. NOx at urban sites and in oil and gas production areas appeared strongly influenced by traffic patterns. At some sites, wind direction analysis and air trajectory analysis indicated that areas of oil and gas production are significant sources of NOx, though pinpointing individual NOx sources proved difficult.

  1. Mars ozone: Mariner 9 revisited

    NASA Technical Reports Server (NTRS)

    Lindner, Bernhard Lee

    1994-01-01

    The efficacy of the UV spectroscopy technique used by Mariner 9 to remotely measure ozone abundance at Mars is discussed. Previously-inferred ozone abundances could be underestimated by as much as a factor of 3, and much of the observed variability in the ozone abundance could be due to temporal and spatial variability in cloud and dust amount.

  2. Ames ER-2 ozone measurements

    NASA Technical Reports Server (NTRS)

    Pearson, R., Jr.; Vedder, James F.; Starr, W. L.

    1990-01-01

    The objective of this research is to study ozone (O3) in the stratosphere. Measurements of the ozone mixing ratio at 1 s intervals are obtained with an ultraviolet photometer which flies on the ER-2 aircraft. The photometer determines the amount of ozone in air by measuring the transmission of ultraviolet light through a fixed path with and without ambient O3 present.

  3. An examination of utility emissions contributions to elevated ozone concentrations in the Chicago area

    SciTech Connect

    Fernau, M.E.; Guziel, K.A.; South, D.W.

    1993-01-01

    In order to reduce the pollutant load to the atmosphere and subsequent damaging effects, Titles I and IV of the Clean Air Act Amendments of 1990 (CAAAs) require reductions in emissions of sulfur dioxide (SO[sub 2]), nitrogen oxides (NO[sub x]), and volatile organic compounds (VOCs). Title IV is aimed at reducing acidic deposition and requires utilities to reduce SO[sub 2] and NO[sub x] emissions to specified levels. As a consequence of this, many utilities will have to install SO[sub 2] and NO[sub x] control technologies. Title I is concerned with bringing regions into compliance with the National Ambient Air Quality Standards (NAAQS) for the criteria pollutants, among which is ozone (O[sub 3]). The NAAQS for O[sub 3] is 120 ppb (parts per billion by volume) hourly average concentration, not to be exceeded four times in three years. O[sub 3] is a secondary pollutant formed in the atmosphere when NO[sub x] and VOCs react together in the presence of sunlight. Utilities are a significant source of NO[sub x] and an unimportant source of VOCs. In the past, O[sub 3] control strategy has focused on reducing VOC emissions because of the possibility that reducing NO[sub x] actually might make O[sub 3] concentrations higher. However, this approach has not worked, perhaps because of underestimation of natural and manmade VOC emissions and transport of O[sub 3] from other regions. Computer modeling has shown that for many highly polluted areas massive NO[sub x] reductions may be necessary in addition to or in place of VOC controls. Utilities are a potential source of these NO[sub x] reductions.

  4. An examination of utility emissions contributions to elevated ozone concentrations in the Chicago area

    SciTech Connect

    Fernau, M.E.; Guziel, K.A.; South, D.W.

    1993-05-01

    In order to reduce the pollutant load to the atmosphere and subsequent damaging effects, Titles I and IV of the Clean Air Act Amendments of 1990 (CAAAs) require reductions in emissions of sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), and volatile organic compounds (VOCs). Title IV is aimed at reducing acidic deposition and requires utilities to reduce SO{sub 2} and NO{sub x} emissions to specified levels. As a consequence of this, many utilities will have to install SO{sub 2} and NO{sub x} control technologies. Title I is concerned with bringing regions into compliance with the National Ambient Air Quality Standards (NAAQS) for the criteria pollutants, among which is ozone (O{sub 3}). The NAAQS for O{sub 3} is 120 ppb (parts per billion by volume) hourly average concentration, not to be exceeded four times in three years. O{sub 3} is a secondary pollutant formed in the atmosphere when NO{sub x} and VOCs react together in the presence of sunlight. Utilities are a significant source of NO{sub x} and an unimportant source of VOCs. In the past, O{sub 3} control strategy has focused on reducing VOC emissions because of the possibility that reducing NO{sub x} actually might make O{sub 3} concentrations higher. However, this approach has not worked, perhaps because of underestimation of natural and manmade VOC emissions and transport of O{sub 3} from other regions. Computer modeling has shown that for many highly polluted areas massive NO{sub x} reductions may be necessary in addition to or in place of VOC controls. Utilities are a potential source of these NO{sub x} reductions.

  5. Western US Tropospheric Ozone: An Assessment of Vertical and Seasonal Variations over California and Nevada

    NASA Technical Reports Server (NTRS)

    Yates, E.; Iraci, Laura T.; Johnson, Matthew; Ryoo, Ju-Mee; Pierce, Bradley R.; Cullis, Patrick; Gore, Warren J. Y.; Ives, Michael; Johnson, Bryan; LeBlanc, Thierry; Sterling, Chance W.; Tanaka, Tomoaki

    2016-01-01

    In the rural western US free-tropospheric O3 has risen in recent years as a result of rising Asian emissions, deep stratospheric intrusions and more frequent wildfires. This increasing O3 trend combined with the high surface elevation of much of the western US, which aids mixing between boundary layer and free-troposphere, pose challenges in attaining the more stringent O3 National Ambient Air Quality Standard (NAAQS) at many western US rural surface sites. As such, the ability to identify various sources and transport mechanisms that contribute towards surface O3 is increasingly important. This paper analyzes vertical profiles of O3 from the Alpha Jet Atmospheric eXperiment (AJAX) over California and Nevada, ozonesondes from Trinidad Head, CA and tropospheric ozone profiles from the differential absorption lidar (DIAL) at the JPL Table Mountain Facility, CA. Surface O3 from the US EPA Clean air Status and Trends Network (CASNET) are used to discuss surface trends. GEOS-Chem determines the trends in regional O3 and assess the contributions of various sources on surface O3. And Realtime Air Quality Modeling System (RAQMS) is used to forecast and interpret free-tropospheric observations. Specifically we will address the following questions: What are the effects of the lowered NAAQS? Do we observe elevated O3 during 2012 at surface sites reported in previous studies? And if so, what are the causes? How variable is free-tropospheric O3 over California and Nevada? How frequently do we observe high O3 lamina in the free troposphere and what are the surface impacts?

  6. Ozone in Rural Nevada: Investigating spatio-temporal patterns and source regions contributing to elevated concentrations

    NASA Astrophysics Data System (ADS)

    Fine, Rebekka

    In 1993, an ozone (O3) monitoring site was established at Great Basin National Park (GBNP), located in rural eastern Nevada. Analyses of data from this site indicate that compliance with a revised National Ambient Air Quality Standard (NAAQS) ≤70 ppb will be challenging. With the exception of GBNP, ambient O3 monitoring has been limited to the areas in and around the 3 urban areas of Nevada. The objectives of the research presented here were to (1) characterize spatial and temporal trends in ambient O 3 across rural Nevada, and (2) identify source regions contributing to elevated O3 in rural Nevada. To pursue these objectives, a network of 13 monitoring sites was established throughout rural Nevada over a period ranging from July 2011 to June 2014. Data from 6 sites during the first 2 years of measurement indicate that maximum MDA8 O3 ranged from 68 to 80 ppb. Ambient O3 measured at GBNP was significantly higher than that measured at other rural Nevada sites. Back trajectory analyses, vertical profile measurements from aircrafts and sondes, statistical analyses, as well as results of regional and global models were employed to identify sources contributing to elevated O3. Our analyses indicate that regional and global sources contribute to O3 at surface sites throughout rural Nevada and that the high elevation and complex terrain make the State ideally situated to intercept air from the free troposphere and thus, pollution derived from complex sources included long-range transport, stratospheric intrusions, and regional emissions. Our data suggest that regional and global cooperation will be necessary to comply with a revised NAAQS in rural Nevada.

  7. MDA8 O3 Values at Rural Surface Sites in Nevada, USA: Results from Two Years of the Nevada Rural Ozone Initiative (NVROI)

    NASA Astrophysics Data System (ADS)

    Gustin, M. S.; Fine, R.; Miller, M. B.; Burley, J. D.; Jaffe, D. A.; Pierce, R. B.; Lin, M.

    2014-12-01

    Local anthropogenic emissions are limited in Nevada (USA); however, data collected at Great Basin National Park (GBNP), which is located in rural eastern Nevada, indicate that ozone (O3) routinely exceeds the threshold proposed for a more stringent National Ambient Air Quality Standard (NAAQS). Here, we focused on data collected between July 2011 and June 2013. For this period, the maximum daily 8-h average (MDA8) O3 at GBNP exceeded the current NAAQS threshold (75 ppb) 7 times. Our analyses indicate that a combination of sources including emissions from regional wildfires and urban areas of southern California as well as stratospheric intrusions and long-range transport of Asian pollution contributed to elevated O3 observed at GBNP. Although MDA8 O3 measured at GBNP was well correlated with that measured at 5 other rural Nevada sites during this period, MDA8 O3 was 3.1 to 12.6 ppb greater at GBNP than at these other rural sites which emphasizes the need for spatially detailed measurements particularly in areas of complex terrain. The maximum MDA8 O3 at these 6 rural NV sites ranged from 68 to 80 ppb. GBNP was the only rural site to exceed the current NAAQS threshold during the period considered; however, when lower thresholds were considered the spatial and temporal extent of exceedances in rural Nevada increased indicating that interstate and international cooperation will be necessary to reduce ambient O3 concentrations in rural Nevada. MDA8 O3 at rural Nevada sites were significantly correlated with measurements at urban Nevada (r = 0.64 to 0.82; p < 0.05) and rural California (r = 0.61 to 0.83; p = 0.00) sites suggesting that common mechanisms influence O3 observed throughout the region.

  8. SAGE II Ozone Analysis

    NASA Technical Reports Server (NTRS)

    Cunnold, Derek; Wang, Ray

    2002-01-01

    Publications from 1999-2002 describing research funded by the SAGE II contract to Dr. Cunnold and Dr. Wang are listed below. Our most recent accomplishments include a detailed analysis of the quality of SAGE II, v6.1, ozone measurements below 20 km altitude (Wang et al., 2002 and Kar et al., 2002) and an analysis of the consistency between SAGE upper stratospheric ozone trends and model predictions with emphasis on hemispheric asymmetry (Li et al., 2001). Abstracts of the 11 papers are attached.

  9. Normally Expected Aberrations in the 8-hour Dynamic EKG

    NASA Technical Reports Server (NTRS)

    Fleck, R. L.; Arnoldi, L. B.; Townsend, J. C.; Tonesk, X.

    1970-01-01

    The establishment of norms for interpreting long term dynamic electrocardiograms is attempted by correlating a completely disease symptom and cardiac risk factor free sample with a non-pure sample in the direction of normality on various variables. Out of a population of 362 subjects exposed to dynamic electrocardiogram testing, a discrimination between normals and abnormals in terms of traditional risk factors was observed. The two groups differed significantly on the following variables: cholesterol, smoking, systolic blood pressure, white blood count, fasting blood sugar, uric acid, resting EKG, year of birth, and coronary insufficiency.

  10. Physicochemical patterns of ozone absorption by wood

    NASA Astrophysics Data System (ADS)

    Mamleeva, N. A.; Lunin, V. V.

    2016-11-01

    Results from studying aspen and pine wood ozonation are presented. The effect the concentration of ozone, the reagent residence time, and the content of water in a sample of wood has on ozone consumption rate and ozone demand are analyzed. The residence time is shown to determine the degree of ozone conversion degree and the depth of substrate destruction. The main patterns of ozone absorption by wood with different moisture content are found. Ways of optimizing the ozonation of plant biomass are outlined.

  11. Total Ozone Prediction: Stratospheric Dynamics

    NASA Technical Reports Server (NTRS)

    Jackman, Charles H.; Kawa, S. Ramdy; Douglass, Anne R.

    2003-01-01

    The correct prediction of total ozone as a function of latitude and season is extremely important for global models. This exercise tests the ability of a particular model to simulate ozone. The ozone production (P) and loss (L) will be specified from a well- established global model and will be used in all GCMs for subsequent prediction of ozone. This is the "B-3 Constrained Run" from M&MII. The exercise mostly tests a model stratospheric dynamics in the prediction of total ozone. The GCM predictions will be compared and contrasted with TOMS measurements.

  12. Precision ozone vapor pressure measurements

    NASA Technical Reports Server (NTRS)

    Hanson, D.; Mauersberger, K.

    1985-01-01

    The vapor pressure above liquid ozone has been measured with a high accuracy over a temperature range of 85 to 95 K. At the boiling point of liquid argon (87.3 K) an ozone vapor pressure of 0.0403 Torr was obtained with an accuracy of + or - 0.7 percent. A least square fit of the data provided the Clausius-Clapeyron equation for liquid ozone; a latent heat of 82.7 cal/g was calculated. High-precision vapor pressure data are expected to aid research in atmospheric ozone measurements and in many laboratory ozone studies such as measurements of cross sections and reaction rates.

  13. Karlson ozone sterilizer. Final report

    SciTech Connect

    Karlson, E.

    1984-05-07

    The authors have a functional sterilization system employing ozone as a sterilization agent. This final report covers the work that led to the first medical sterilizer using ozone as the sterilizing agent. The specifications and the final design were set by hospital operating room personnel and public safety standards. Work on kill tests using bacteria, viruses and fungi determined the necessary time and concentration of ozone necessary for sterilization. These data were used in the Karlson Ozone Sterilizer to determine the length of the steps of the operating cycle and the concentration of ozone to be used. 27 references.

  14. High efficiency ozone generation system

    SciTech Connect

    Karlson, E.L.

    1990-01-09

    This final report entails research prepared to verify the workings and the efficiency of producing ozone with the ELK'' Ozone Generator, which operates at an elevated gas pressure of up to 20 MPA (3000 psi) and is an improvement of the corona discharge ozone generator. The increased pressure produces an increase in the density of oxygen gas fed into the generator. This, in turn, leads to an increased yield of ozone in the ozone oxygen gas mixture leaving the generator. The design of this new ozone generator incorporates a novel positioning of the dielectric to preserve its mechanical integrity at high operating pressures and also incorporates a novel heat removal technique. A large number of ozone production runs have been made at different pressures. Large populations of data such as, temperature points throughout the generator, gas flow, cooling water flow parameters, operating gas pressure, ozone concentration, and data on the dielectric cooling, have been compiled and fed into our computer. This new data indicates not only that high pressures used in a controlled fashion will produce more ozone per watt hour but also indicates what problems exist when pressures are increased, such as the generation of high temperatures not only in the area of ozone generation but within the dielectric. The data also shows the necessary residence time for maximum ozone production at a particular pressure, voltage, temperature and electrode spacing. 14 refs., 22 figs.

  15. Assimilation of Satellite Ozone Observations

    NASA Technical Reports Server (NTRS)

    Stajner, I.; Winslow, N.; Wargan, K.; Hayashi, H.; Pawson, S.; Rood, R.

    2003-01-01

    This talk will discuss assimilation of ozone data from satellite-borne instruments. Satellite observations of ozone total columns and profiles have been measured by a series of Total Ozone Mapping Spectrometer (TOMS), Solar Backscatter Ultraviolet (SBUV) instruments, and more recently by the Global Ozone Monitoring Experiment. Additional profile data are provided by instruments on NASA's Upper Atmosphere Research Satellite and by occultation instruments on other platforms. Instruments on Envisat' and future EOS Aura satellite will supply even more comprehensive data about the ozone distribution. Satellite data contain a wealth of information, but they do not provide synoptic global maps of ozone fields. These maps can be obtained through assimilation of satellite data into global chemistry and transport models. In the ozone system at NASA's Data Assimilation Office (DAO) any combination of TOMS, SBUV, and Microwave Limb sounder (MLS) data can be assimilated. We found that the addition of MLS to SBUV and TOMS data in the system helps to constrain the ozone distribution, especially in the polar night region and in the tropics. The assimilated ozone distribution in the troposphere and lower stratosphere is sensitive also to finer changes in the SBUV and TOMS data selection and to changes in error covariance models. All results are established by comparisons of assimilated ozone with independent profiles from ozone sondes and occultation instruments.

  16. Ozone decomposing filter

    SciTech Connect

    Simandl, R.F.; Brown, J.D.; Whinnery, L.L. Jr.

    1999-11-02

    In an improved ozone decomposing air filter carbon fibers are held together with a carbonized binder in a perforated structure. The structure is made by combining rayon fibers with gelatin, forming the mixture in a mold, freeze-drying, and vacuum baking.

  17. The Ozone Show.

    ERIC Educational Resources Information Center

    Mathieu, Aaron

    2000-01-01

    Uses a talk show activity for a final assessment tool for students to debate about the ozone hole. Students are assessed on five areas: (1) cooperative learning; (2) the written component; (3) content; (4) self-evaluation; and (5) peer evaluation. (SAH)

  18. Ozone decomposing filter

    DOEpatents

    Simandl, Ronald F.; Brown, John D.; Whinnery, Jr., LeRoy L.

    1999-01-01

    In an improved ozone decomposing air filter carbon fibers are held together with a carbonized binder in a perforated structure. The structure is made by combining rayon fibers with gelatin, forming the mixture in a mold, freeze-drying, and vacuum baking.

  19. Dobson ozone spectrophotometer modification.

    NASA Technical Reports Server (NTRS)

    Komhyr, W. D.; Grass, R. D.

    1972-01-01

    Description of a modified version of the Dobson ozone spectrophotometer in which several outdated electronic design features have been replaced by circuitry embodying more modern design concepts. The resulting improvement in performance characteristics has been obtained without changing the principle of operation of the original instrument.

  20. Ozone, CFCs and aerosols.

    PubMed

    1989-07-01

    Chlorofluorocarbons (CFCs) are, from the chemist's point of view, unique compounds with very valuable properties. They are inert, cheap and stable. But they also have devastating effects on the environment, destroying the ozone layer and adding to global warming or the greenhouse effect.

  1. Ozone Layer Educator's Guide.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    This guide has been developed through a collaborative effort involving the U.S. Environmental Protection Agency (EPA), the National Oceanic and Atmospheric Administration (NOAA), and the National Aeronautics and Space Administration (NASA). It is part of an ongoing commitment to ensure that the results of scientific research on ozone depletion are…

  2. Ozone and Cavitation Combination

    NASA Astrophysics Data System (ADS)

    Carreon, Ernestina; Traversoni, Leonardo

    2009-09-01

    From laboratory measurements it is well known that the addition of ozone and cavitation enhances the properties of both, understanding for that the ones related to disinfection and carbon removal from waste water. This paper shows modeling of such phenomena that gives some light to the understanding of it and also provides the opportunity to improve the effectiveness of the current procedures.

  3. Assessing the Influence of Western Boundary Ozone Inflow for the Pacific Northwest Using the AIRPACT-4 Air-Quality Forecast System

    NASA Astrophysics Data System (ADS)

    Vaughan, J. K.; Chung, S. H.; Herron-Thorpe, F. L.; Lamb, B. K.; Zhang, R.; Mount, G. H.; Emmons, L. K.

    2013-12-01

    The AIRPACT project has provided state, local and tribal air quality managers in the Pacific and Inland Northwest with state-of-the-art near-real time air quality forecasts, beginning in 2001 (Vaughan et al., 2004). Air-quality modeling is also an important tool for evaluating strategies for complying with the NAAQS, especially as the ozone standard is likely to be tightened from 75 ppb to 60 - 70 ppb. For the Pacific Northwest a perennial issue is the significance of trans-boundary transport effects on air quality. Under the EPA Exceptional Events Policy, for example, a nominal exceedance can be excluded from design value calculation if it can be credibly ascribed to long-range transport (LRT); air-quality modeling is an accepted tool for making a case that LRT contributes to an exceedance, and thus qualifies as an Exceptional Event. Also, evidence is accumulating that local air pollution should sometimes be viewed in the context of baseline pollution levels, and that these baseline levels are influenced by LRT (Wigder et al., 2013). AIRPACT4, a WRF-SMOKE-CMAQ air quality modeling system, uses chemical boundary conditions from global MOZART4 model runs that assimilate MOPITT/TERRA satellite CO (Herron-Thorpe et al., 2012). Here we use a non-reactive tracer species version of CMAQv4.7.1 to develop a chemical climatology describing trans-boundary ozone contributions (across the western boundary only) to the ozone background of the Pacific Northwest, including ozone input to the domain from trans-Pacific transport originating in Asia. Discrete tracers are assigned to the boundary condition ozone from each of the 21 model layers. The modeling results are analyzed for ozone-season months to determine: 1) monthly statistics on the ratio of trans-boundary tracer ozone to standard AIRPACT4 ground level ozone, and 2) the contribution of trans-boundary tracer ozone to episodes of high ozone concentration. Preliminary results will be presented along with discussion of

  4. 16 CFR 260.11 - Ozone-safe and ozone-friendly claims.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... friendly to, the ozone layer or the atmosphere. Example 1: A product is labeled “ozone-friendly.” The claim... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Ozone-safe and ozone-friendly claims. 260.11... THE USE OF ENVIRONMENTAL MARKETING CLAIMS § 260.11 Ozone-safe and ozone-friendly claims. It...

  5. 16 CFR 260.11 - Ozone-safe and ozone-friendly claims.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... friendly to, the ozone layer or the atmosphere. Example 1: A product is labeled “ozone-friendly.” The claim... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Ozone-safe and ozone-friendly claims. 260.11... THE USE OF ENVIRONMENTAL MARKETING CLAIMS § 260.11 Ozone-safe and ozone-friendly claims. It...

  6. Precision ozone calibration system based on vapor pressures of ozone

    NASA Technical Reports Server (NTRS)

    Mauersberger, K.; Hanson, D.; Morton, J.

    1987-01-01

    A precision ozone calibration system for stratospheric research has been developed and evaluated. Vapor pressures above solid ozone are mixed with a carrier gas (N2) to produce stratospheric ozone mixing ratios at total pressures of 1 to cover 20 torr. The uncertainty in the ozone mixing ratios is approximately + or - 1.5 percent, the stability of ozone is + or - 0.3 percent. Experiments to be calibrated may sample the gas mixture over a wide range of flow rates; the maximum throughput of gas with corrections of less than 1 percent to ozone is about 200 torr 1/min. A mass spectrometer system continuously monitors the purity and stability of the N2-O3 gas mixture.

  7. [Ozone source apportionment at urban area during a typical photochemical pollution episode in the summer of 2013 in the Yangtze River Delta].

    PubMed

    Li, Hao; Li, Li; Huang, Cheng; An, Jing-yu; Yan, Ru-sha; Huang, Hai-ying; Wang, Yang-jun; Lu, Qing; Wang, Qian; Lou, Sheng-rong; Wang, Hong-li; Zhou, Min; Tao, Shi-kang; Qiao, Li-ping; Chen, Ming-hua

    2015-01-01

    With the fast development of urbanization, industrialization and mobilization, the air pollutant emissions with photochemical reactivity become more obvious, causing a severe photochemical pollution with the characteristics of high ozone concentration. However, the ozone source identification is very complicated due to the high non linearity between ozone and its precursors. Thus, ways to reduce ozone is still not clear. A high ozone pollution episode occurred during July, 2013, which lasted for a long period, with large influence area and high intensity. In this paper, we selected this episode to do a case study with the application of ozone source apportionment technology(OSAT) coupled within the CAMx air quality model. In this study, 4 source regions(including Shanghai, north Zhejiang, South Jiangsu and long range transport), 7 source categories (including power plants, industrial process, industrial boilers and kilns, residential, mobile source, volatile source and biogenic emissions) are analyzed to study their contributions to surface O3 in Shanghai, Suzhou and Zhejiang. Results indicate that long range transport contribution to the surface ozone in the YRD is around 20 x 10(-9) - 40 x 10(-9) (volume fraction). The O3 concentrations can increased to 40 x 10(-9) - 100 x 10(-9) (volume fraction) due to precursors emissions in Shanghai, Jiangsu and Zhejiang. As for the regional contribution to 8 hour ozone, long range transport constitutes 42.79% +/- 10.17%, 48.57% +/- 9.97% and 60.13% +/- 7.11% of the surface ozone in Shanghai, Suzhou and Hangzhou, respectively. Regarding the high O3 in Shanghai, local contribution is 28.94% +/- 8.49%, north Zhejiang constitutes 19.83% +/- 10.55%. As for surface O3 in Suzhou, the contribution from south Jiangsu is 26.41% +/- 6.80%. Regarding the surface O3 in Hangzhou, the major regional contributor is north Zhejiang (29.56% +/- 8.33%). Contributions from the long range transport to the daily maximum O3 concentrations are

  8. Measurement of ozone production sensor

    NASA Astrophysics Data System (ADS)

    Cazorla Andrade, Maria Del Carmen

    The Measurement of Ozone Production Sensor (MOPS) is a new ambient air monitor that measures directly the rate of ozone production in the atmosphere. The sensor consists of two environmental chambers made of UV-transmitting Teflon film continuously exposed to the solar radiation, a unit to convert NO2 to O3, and a modified ozone monitor. In the sample chamber, photolysis processes and radical chemistry produce ozone just as it happens in the atmosphere. In the second chamber, called the reference chamber, a UV-blocking film prevents radical formation in a way that only the photostationary state component of ozone formation is retained. High-efficiency conversion of NO2 to O3 accounts for differences in the NOx photostationary state between both chambers. An ozone monitor operating without its ozone scrubber detects the ozone differential between the sample and the reference chamber. By doing so, the photostationary state component of ozone formation is canceled out and the ozone produced via radical chemistry is detected. The ozone differential is divided by the exposure time of the air in the chambers to find the rate of ozone production. Radical abundance measurements, wall loss tests and radiometric measurements demonstrate the feasibility of the technique. The MOPS was deployed in a rural environment, on the campus of Penn State University (September 2008), and in an urban environment, in Houston during the Study of Houston Atmospheric Radical Precursors SHARP (15 Apr to 31 May, 2009). The MOPS retrieved the first experimental plots of ambient P(O 3) vs. NO in both locations. In addition, the sensitivity of ozone production in these two environments was studied by adding NOx mixtures to the ambient air and looking at the response in the production of ozone. The results presented in this work demonstrate how an extended use of the MOPS can contribute to the improvement of air quality regulations by quantifying ozone production and ozone transport at a regional

  9. TOMS Ozone Anomalies and Ozone Retrieval Errors Over Cloudy Areas

    NASA Astrophysics Data System (ADS)

    Liu, X.; Newchurch, M.; Kim, J.; Bhartia, P. K.; Loughman, R.

    2003-12-01

    This study characterizes TOMS Ozone Retrieval Errors (OREs) associated with incorrect Cloud-Top Pressures (CTPs) and with assuming opaque Lambertian clouds, investigates these errors' effects on tropospheric ozone derivation, and analyzes ozone anomalies over TOMS data. Large errors occurring in TOMS assumed CTPs and inaccurate CTP-caused OREs are most significantly from inappropriately added ozone below clouds. Because OREs are usually within the TOMS retrieval precision when Cloud Optical Depth (COD)>20, assuming Lambertian surface is good. Because of In-Cloud Ozone Absorption ENhancement (ICOAEN), assuming opaque clouds can introduce large positive OREs even for optically thick clouds. For a 2-12 km water cloud of COD 40 with 20.8 DU ozone inside the cloud, the ORE is 17.8 DU at nadir. The ICOAEN effect depends strongly on viewing geometry and inter-cloud ozone amount and distribution; it is typically 5-13 DU over the tropical Atlantic and Africa and 1-7 DU over the tropical Pacific for deep convective clouds. The negative errors from using the TOMS Partial Cloud Model (PCM) partly cancel other positive errors. At COD < 5, the TOMS algorithm retrieves approximately the correct total ozone because of compensating errors. With increasing COD up to 20-40, negative PCM effect decreases to almost zero, and the overall positive ORE increases and is dominated by ICOAEN effect. The ICOAEN effect can largely underestimate tropospheric ozone derived from cloudy/clear difference techniques. The convective cloud differential and cloud-clear pair methods use minimum ozone above clouds to cancel positive errors. A Positive or Negative Ozone Anomaly (POA/NOA) is defined to occur if the ozone/reflectivity correlation coefficient in a region is >0.5 or <-0.5. Average fractions of OA occurrence are 31.8% and 35.8% in Nimbus-7 and Earth-Probe TOMS data, respectively. Most tropical NOAs result from large cloud-height errors; corrections lead to 50-70% POAs in the tropics because of

  10. Ozonated olive oils and the troubles

    PubMed Central

    Uysal, Bulent

    2014-01-01

    One of the commonly used methods for ozone therapy is ozonated oils. Most prominent type of used oils is extra virgin olive oil. But still, each type of unsaturated oils may be used for ozonation. There are a lot of wrong knowledge on the internet about ozonated oils and its use as well. Just like other ozone therapy studies, also the studies about ozone oils are inadequate to avoid incorrect knowledge. Current data about ozone oil and its benefits are produced by supplier who oversees financial interests and make misinformation. Despite the rapidly increasing ozone oil sales through the internet, its quality and efficacy is still controversial. Dozens of companies and web sites may be easily found to buy ozonated oil. But, very few of these products are reliable, and contain sufficiently ozonated oil. This article aimed to introduce the troubles about ozonated oils and so to inform ozonated oil users. PMID:26401346

  11. The role of refinery flaring events and bay breezes on a high surface ozone episode during the Houston, Texas DISCOVER-AQ field campaign

    NASA Astrophysics Data System (ADS)

    Loughner, C.; Follette-Cook, M. B.; Fried, A.; Pickering, K. E.

    2015-12-01

    The highest observed surface ozone concentrations in the Houston metropolitan area in 2013 occurred on September 25, which coincided with the Texas DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign. Surface ozone was elevated throughout the Houston metropolitan area with maximum 8-hour average ozone peaking along the western shore of Galveston Bay, reaching 124 ppbv, almost 50 ppbv above the current EPA standard of 75 ppbv. The NASA P-3B aircraft observed plumes from refinery flares west and northwest of Galveston Bay that were transported over the water. Continental air pollution from the north was transported into the Houston metropolitan area where it mixed with locally generated emissions. A bay breeze circulation formed causing pollutants that were transported out over the water in the morning to recirculate back inland where they mixed with freshly emitted pollution near the bay breeze convergence zone. The highest surface ozone concentrations were reported near the bay breeze front. This ozone episode will be presented using measurements made during the DISCOVER-AQ field campaign and a CMAQ model simulation with integrated source apportionment, which tracks the contribution of emissions source groups and regions on ozone concentrations.

  12. Three air quality studies: Great Lakes ozone formation and nitrogen dry deposition; and Tucson aerosol chemical characterization

    NASA Astrophysics Data System (ADS)

    Foley, Theresa

    The Clean Air Act of 1970 was promulgated after thousands of lives were lost in four catastrophic air pollution events. It authorized the establishment of National Ambient Air Quality Standards or (NAAQS) for six pollutants that are harmful to human health and welfare: carbon monoxide, lead, nitrogen dioxide, particulate matter, ozone and sulfur dioxide. The Clean Air Act also led to the establishment of the United Stated Environmental Protection Agency (US EPA) to set and enforce regulations. The first paper in this dissertation studies ozone in the Lake Michigan region (Foley, T., Betterton, E.A., Jacko, R., Hillery, J., 2011. Lake Michigan air quality: The 1994-2003 LADCO Aircraft Project (LAP). Atmospheric Environment 45, 3192-3202.) The Chicago-Milwaukee-Gary metropolitan area has been unable to meet the ozone NAAQS since the Clean Air Act was implemented. The Lake Michigan Air Directors' Consortium (LADCO) hypothesized that land breezes transport ozone precursor compounds over the lake, where a large air/water temperature difference creates a shallow conduction layer, which is an efficient reaction chamber for ozone formation. In the afternoon, lake breezes and prevailing synoptic winds then transport ozone back over the land. To further evaluate this hypothesis, LADCO sponsored the 1994-2003 LADCO Aircraft Project (LAP) to measure the air quality over Lake Michigan and the surrounding areas. This study has found that the LAP data supports this hypothesis of ozone formation, which has strong implications for ozone control strategies in the Lake Michigan region. The second paper is this dissertation (Foley, T., Betterton, E.A., Wolf, A.M.A., 2012. Ambient PM10 and metal concentrations measured in the Sunnyside Unified School District, Tucson, Arizona. Journal of the Arizona-Nevada Academy of Science, 43, 67-76) evaluated the airborne concentrations of PM10 (particulate matter with an aerodynamic diameter of 10 microns or less) and eight metalloids and metals

  13. Secular variations of tropospheric ozone

    NASA Astrophysics Data System (ADS)

    Khrgian, A. Kh.

    1988-02-01

    The dependence of secular variations of tropospheric ozone on decreases of temperature and cloud growth in Central Europe is assessed on the basis of Vienna, Paris, and Athens data for 1853-1920. Decreases in ozone content occurring with a certain time lag after major volcanic eruptions (e.g., Krakatoa) are examined. The effect of the Tungusk-meteorite fall on ozone content is also discussed.

  14. Mars ozone: Mariner 9 revisited

    NASA Technical Reports Server (NTRS)

    Lindner, Bernhard Lee

    1995-01-01

    The efficacy of the UV reflectance spectroscopy technique used by Mariner 9 to remotely measure ozone abundance at Mars is discussed. Due to temporal and spatial variability in cloud and dust amount, previously inferred ozone abundances could be underestimated by a factor of 3. Until the large uncertainty in cloud and dust scattering properties and opacities can be reduced, the ozone abundance inferred by the reflectance spectroscopy technique will always have significant uncertainty.

  15. Ozone Health Risk Assessment for Selected Urban Areas

    EPA Pesticide Factsheets

    The health risk assessment described in this report estimated various health effects associated with O3 exposures as well as the reduced risks for one O3 season associated with just meeting the current O3 NAAQS.

  16. Protecting beans from ozone

    SciTech Connect

    Pierce, R.

    1983-03-01

    A chemical treatment to protect navy beans from ozone damage increased yields by an average of more than 20% in 3 years of tests. An experimental antioxidant chemical, EDU, made by the DuPont company was tested as soil applications and sprays on several varieties and under a variety of soil and planting conditions. The average yield increases were between 16 and 24%. Chemical treatment also increased snap bean pod production by 12%.

  17. Protecting the ozone layer.

    PubMed

    Munasinghe, M; King, K

    1992-06-01

    Stratospheric ozone layer depletion has been recognized as a problem by the Vienna Convention for the Protection of the Ozone Layer and the 1987 Montreal Protocol (MP). The ozone layer shields the earth from harmful ultraviolet radiation (UV-B), which is more pronounced at the poles and around the equator. Industrialized countries have contributed significantly to the problem by releasing chlorofluorocarbons (CFCs) and halons into the atmosphere. The effect of these chemicals, which were known for their inertness, nonflammability, and nontoxicity, was discovered in 1874. Action to deal with the effects of CFCs and halons was initiated in 1985 in a 49-nation UN meeting. 21 nations signed a protocol limiting ozone depleting substances (ODS): CFCs and halons. Schedules were set based on each country's use in 1986; the target phaseout was set for the year 2000. The MP restricts trade in ODSs and weights the impact of substances to reflect the extent of damage; i.e., halons are 10 times more damaging than CFCs. ODS requirements for developing countries were eased to accommodate scarce resources and the small fraction of ODS emissions. An Interim Multilateral Fund under the Montreal Protocol (IMFMP) was established to provide loans to finance the costs to developing countries in meeting global environmental requirements. The IMFMP is administered by the World Bank, the UN Environmental Program, and the UN Development Program. Financing is available to eligible countries who use .3 kg of ODS/person/year. Rapid phaseout in developed countries has occurred due to strong support from industry and a lower than expected cost. Although there are clear advantages to rapid phaseout, there were no incentives included in the MP for rapid phaseout. Some of the difficulties occur because the schedules set minimum targets at the lowest possible cost. Also, costs cannot be minimized by a country-specific and ODS-specific process. The ways to improve implementation in scheduling and

  18. Ozone measurement systems improvements studies

    NASA Technical Reports Server (NTRS)

    Thomas, R. W.; Guard, K.; Holland, A. C.; Spurling, J. F.

    1974-01-01

    Results are summarized of an initial study of techniques for measuring atmospheric ozone, carried out as the first phase of a program to improve ozone measurement techniques. The study concentrated on two measurement systems, the electro chemical cell (ECC) ozonesonde and the Dobson ozone spectrophotometer, and consisted of two tasks. The first task consisted of error modeling and system error analysis of the two measurement systems. Under the second task a Monte-Carlo model of the Dobson ozone measurement technique was developed and programmed for computer operation.

  19. Evaluating 2012 Ozone Impacts of Natural Gas Development in the Haynesville Shale with an Updated Emission Inventory

    NASA Astrophysics Data System (ADS)

    Kemball-Cook, S. R.; Bar-Ilan, A.; Yarwood, G.

    2013-12-01

    The Haynesville Shale, located approximately 10,000-13,000 feet beneath Northeast Texas and Northwest Louisiana contains very large recoverable reserves of natural gas. Development of the Haynesville began in 2008, and since then, more than 3,000 wells have been drilled. The development of natural gas resources in the Haynesville is economically important, but also generates emissions of ozone precursors in a region with several ozone monitors that are close to or exceeding the 2008 National Ambient Air Quality Standard. During 2009, we developed an emission inventory of ozone precursors for projected future Haynesville Shale development from 2009 through 2020. Photochemical modeling with the 2012 emission inventory showed significant ozone impacts within Northeast Texas and Northwest Louisiana as a result of Haynesville emissions, with projected 8-hour ozone design value increases up to 5 ppb at area monitors. The original emission inventory was assembled during spring 2009, early in the development of the Haynesville when available data were limited. Since then, development in the Haynesville has continued, and additional data are now available and were used to refine the development projections and emission inventory through the year 2020. The updated 2012 emission inventory is now based on actual data rather than projections made in 2009. The number of drilling rigs operating in 2012 was lower than projected, but the well count was higher due intensive drilling activity in 2010-2011 that exceeded projections. The updated emission inventory draws on more Haynesville-specific data than the previous inventory. Energy producers currently active in the Haynesville were surveyed and provided information that included well drilling times, equipment used for well construction, production equipment present at typical Haynesville wells, and produced gas composition analyses. Producers provided information on the amount of truck traffic associated with transport of

  20. Comparing and evaluating model estimates of background ozone in surface air over North America

    NASA Astrophysics Data System (ADS)

    Oberman, J.; Fiore, A. M.; Lin, M.; Zhang, L.; Jacob, D. J.; Naik, V.; Horowitz, L. W.

    2011-12-01

    Tropospheric ozone adversely affects human health and vegetation, and is thus a criteria pollutant regulated by the U.S. Environmental Protection Agency (EPA) under the National Ambient Air Quality Standard (NAAQS). Ozone is produced in the atmosphere via photo-oxidation of volatile organic compounds (VOCs) and carbon monoxide (CO) in the presence of nitrogen oxides (NOx). The present EPA approach considers health risks associated with exposure to ozone enhancement above the policy-relevant background (PRB), which is currently defined as the surface concentration of ozone that would exist without North American anthropogenic emissions. PRB thus includes production by natural precursors, production by precursors emitted on foreign continents, and transport of stratospheric ozone into surface air. As PRB is not an observable quantity, it must be estimated using numerical models. We compare PRB estimates for the year 2006 from the GFDL Atmospheric Model 3 (AM3) chemistry-climate model (CCM) and the GEOS-Chem (GC) chemical transport model (CTM). We evaluate the skill of the models in reproducing total surface ozone observed at the U.S. Clean Air Status and Trends Network (CASTNet), dividing the stations into low-elevation (< 1.5 km in altitude, primarily eastern) and high-elevation (> 1.5 km in altitude, all western) subgroups. At the low-elevation sites AM3 estimates of PRB (38±9 ppbv in spring, 27±9 ppbv in summer) are higher than GC (27±7 ppbv in spring, 21±8 ppbv in summer) in both seasons. Analysis at these sites is complicated by a positive bias in AM3 total ozone with respect to the observed total ozone, the source of which is yet unclear. At high-elevation sites, AM3 PRB is higher in the spring (47±8 ppbv) than in the summer (33±8 ppbv). In contrast, GC simulates little seasonal variation at high elevation sites (39±5 ppbv in spring vs. 38±7 ppbv in summer). Seasonal average total ozone at these sites was within 4 ppbv of the observations for both