Thomas Robinson | July 14th, 2020
After July 4th celebrations earlier this month Des Moines had the worst air quality in the country measured at an Air Quality Index (AQI) of 588.
Fireworks shot off overnight on July 4th triggered an air quality advisory from July 5th into the morning of July 6th. The highest reading occurred early in the morning on the 5th with conditions returning to safer levels later on that day. The poor air conditions were caused by a high pressure weather system with slow moving air that prevented the movement, and dissipation, of pollutants away from Des Moines.
The AQI is a national metric used to describe air quality through reporting on common air pollutants listed in the Clean Air Act. There are six AQI levels which range from good (0-50) to hazardous (301 and above). Local air quality can be found using AirNow, which supplies the AQI and also which pollutant is primarily responsible for any poor air quality.
When the AQI is as high as it was in Des Moines (588) pollution in the air poses a noticeable risk to human health. Symptoms of poor air quality can include irritation of eyes or nose, shortness of breath and coughing. When poor air quality conditions like in Des Moines persist outside activity should be avoided to limit inhalation exposure to pollution.