Smoke Triggers Air Quality Alerts Across Colorado

An action day alert for pollution was issued Saturday for the Front Range and Eastern Plains.

Fine particulate matter concentrations from wildfire smoke are expected to be in the 'unhealthy' to 'unhealthy for sensitive groups' categories Saturday, and visibility will be in the 'extremely poor' category in Denver.

Ozone concentrations are expected to be in the 'unhealthy for sensitive groups' to 'moderate' categories throughout the Front Range and foothills, the Colorado Department of Public Health and Environment said.

"People with heart or lung disease, older adults, and children should avoid prolonged or heavy exertion on Saturday; everyone else should reduce prolonged or heavy exertion on Saturday," the agency said in its alert.

Carbon monoxide and nitrogen dioxide levels are expected to be in the 'good' category Saturday, health officials said.

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Dozens of action day alerts for ozone have been issued for metro Denver and Boulder so far this summer. Metro Denver is the 8th worst metro area in the nation for high ozone days, according to the American Lung Association's 2021 "State of the Air" report.

Ozone pollution, often called smog, forms when gases that come out of tailpipes and smokestacks, among other sources, come into contact with sunlight. Ozone is "one of the most dangerous and widespread pollutants in the U.S.," the lung association said.

Ozone can damage people's airways, make their lungs more susceptible to infection and aggravate lung diseases, according to the U.S. Environmental Protection Agency.

>> Read the full air quality advisory here.