Ozone W126 Data Resources
On January 6, 2010, EPA proposed to strengthen the national ambient air quality standards (NAAQS) for ground-level ozone. As part of this action, EPA is proposing to establish a distinct cumulative, seasonal "secondary" standard, designed to protect sensitive vegetation and ecosystems. The form of this new proposed secondary standard is a "cumulative peak-weighted index," called W126. EPA is proposing to set the level of the secondary standard within the range of 7-15 ppm-hours.
Here is a list of resources for accessing and calculating W126 index values.
- Instructions for calculating the W126 index value (PDF, 67 KB)
- Excel file with Daily Index calculation programmed (XLS, 22 KB)
- Excel file with 3-year W126 design value calculation programmed (XLS, 747 KB)
- Get calculated W126 data from AQS [Note: The W126 statistics available here are based on the proposed Part 50, Appendix P data handling guidelines (pp.3051-3052), EXCEPT no hourly substitutions are made for months with less than 75% data completeness as prescribed in section 4.c.ii.]
Here is the 2006-2008 W126 data provided with the January 6, 2010 proposal.