Healthy Air

Colorado hits 35 Ozone Alert days so far this year

The state has had 35 days since June 1 when ozone levels were expected to spike to unhealthy levels.

Clean air

Haze visible over downtown Denver as seen from Red Rocks.

As of Aug. 24, Coloradans living and working along the Front Range have experienced 35 Ozone Action Alert Days – days when the levels of ozone pollution in the air are expected to spike to levels making it unhealthy to breathe. Ten of these alerts have occurred during the past 11 days.

Exposure to elevated ozone levels can cause harmful health effects including lung damage, worsening of existing respiratory conditions such as asthma, and even cardiovascular disease.

For more information on where our ozone pollution comes from, and what we can do to make our air safer to breathe, visit

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