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Historical Data
Ozone and PM2.5 Exceedance Summary
The Excel file named Ozone and Particle Pollution Exceedance Summary in the listing below contains the exceedance summary for each year since 2005. Ozone season officially runs from April 1st through September 30th. Since exceedances have previously occurred in March, every effort is made to bring the monitors back up as soon as practical each year.
The exceedance summary document lists the exceedances for both pollutants for each year. On the tab for each year, entries are in chronological order and include the date, site(s) and value when any site had exceeded the National Ambient Air Quality Standard for Ozone (NAAQS). The ozone NAAQS is 0.070 parts per million (70 parts per billion). The particle pollution short-term NAAQS is the midnight to midnight 24-hour average.
Ozone and Particle Pollution Exceedance Summary (Excel)
Quality Assured Analyzed Data
The quality assured (QA'd) data for ozone and particle pollution for recent years is contained in the appropriate file below.
Ozone data is the maximum 8-hour average for the day at each site.
Particle pollution data is the midnight to midnight 24-hour average for each day. Please read the material on the first worksheet in the file for important information to keep in mind when viewing the data.