AirHistory — Air Quality Trends & Grades for 1,000+ US Cities

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D

Boulder, Colorado, CO

Air Quality Grade: 48/100

Median AQI: 50. Trend: Worsening.

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Data from AirHistory

AirHistory

10-year air quality trends for every US city. Data from EPA Air Quality System (AQS), updated annually.

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Data sourced from EPA Air Quality System (AQS). Not affiliated with the US Environmental Protection Agency.