Public health officials in Colorado announced an “Ozone Action Day Alert” beginning 4 p.m. Thursday and ending at midnight due to “hot and stagnant” conditions that were expected to result in unhealthy ozone levels. Local residents were even encouraged to give up car trips.
Per a press release from the Colorado Department of Public Health, the alert covers the Front Range Urban Corridor from Douglas County north to Larimer and Weld counties, including the Denver-Boulder area, Fort Collins and Greeley. In that area, the ozone is expected to “reach levels that are Unhealthy for Sensitive Groups,’ said the department.
According to the U.S. Environmental Protection Agency, ozone is simply a gas made from three atoms of oxygen. When it is in the upper atmosphere where it belongs, ozone is good, but at ground level – where humans can breathe it in – ozone can cause adverse health effects such as coughing and difficulty breathing. People with lung conditions are especially vulnerable to the impacts of ozone.
“Tropospheric, or ground level ozone, is not emitted directly into the air, but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC),” the EPA explained. “This happens when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources chemically react in the presence of sunlight.”
That’s why the Colorado Department of Public Health urged state residents to reduce personal emissions in an effort to shrink ozone production.
“Combining or skipping just two car trips a week has a positive impact on our air quality,” it said.
Newsweek reported that the recent ozone alert from Colorado was for an area with hundreds of thousands of people. It warned against prolonged outdoor exertion, especially for people who might be sensitive to ozone.
“Ground-level ozone is an air pollution problem that impacts the health of all Coloradans,” said the public health department. “Exposure can cause acute respiratory problems and trigger asthma attacks. During Ozone Action Alerts, avoid rigorous outdoor activity during the heat of the day. Prolonged exposure can cause long-lasting damage to your lungs.”
Action day alerts in Colorado are measures taken when fine particulate matter, carbon monoxide, ozone or other pollutants are at unhealthy levels. They trigger “a variety of mandatory and voluntary pollution prevention measures,” the public health department explained. These measures include temporary restrictions on open burning.
Colorado isn’t the only state in the U.S. dealing with the negative impacts of ozone pollution. According to the American Lung Association, “ozone air pollution is making breathing difficult for more people living in the U.S. than any other single pollutant,” with more than 125 million people exposed to risky levels of ozone from 2021 through 2023 – about 37% of the U.S. population.