Air Quality in Maine

Notes: Data is for the current/most recent hour available; time remains on EST year-round; data is preliminary and has not been through the quality assurance process. Values over 900 signify an error and are not actual measurements.

Ozone levels in Maine are higher during the warmer months and lower during the cooler months. Therefore, during the cooler months many of the monitors are turned off so data is only available from a few sites. During the warmer months data will be available from all our ozone sites.

Tips for using the maps View +

  • To see what each symbol color represents, click the legend icon map icon located in the top right corner of each map.
  • Click on each location in the map to see the site name and concentration for the hour displayed.
  • A gray circle on either map indicates no data was available during the hour for that site. Concentrations will show as zero in their respective pop-up(s).
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Dealing with Browser Issues View +

    It has been discovered that several internet browsers tend to hold onto previous images of these maps. This is especially true for those who check the page frequently. If you discover the map hasn’t updated, to the last update hour displayed by the unedited hour data page, there are several things you can do:


  • Refresh the image – hold down the control key while clicking on the refresh option in your browser
  • Clear the browser history – go to your browsing history and clear the browsing data
  • Open a different browser

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Click here to open a full-screen version of this map. - WEBMAP-APP - (Ideal for Smart Phones and Tablets)

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