DES MOINES -- Exceedances of the National Ambient Air Quality Standards (NAAQS) for fine particulates are expected today over the eastern third of the state. Smoke from wildfires in both eastern and northwestern Canada has converged over Iowa and is expected to lead to fine particulate matter exceedances over eastern and east-central Iowa today.
The smoke may linger over the area and affect air quality in the coming days until a significant weather system sweeps it out of the area. Wildfire smoke carries large amounts of particulates as well as gases that may act as ozone precursors and can lead to exceedances of the NAAQS for both fine particulate matter and ozone.
The national standard for fine particulate matter is 35 micrograms per cubic meter (µg/m3) averaged over a 24-hour period, and this level is considered “unhealthy for
sensitive groups.” Groups sensitive to particulate matter include people with heart or lung disease, older adults, children and teenagers, and outdoor workers. Fine
particulate levels could reach levels considered “unhealthy” where even healthy adults should consider limiting their activities.
Real-time air quality maps and information about the air quality index can be found on EPA’s airnow.gov site. A graphic approximation of the extent and trajectory of the smoke plume can be seen on the map at fire.airnow.gov/.
EPA’s specific guidelines on what precautions can be taken to minimize the impact of high ozone and fine particulate levels are available at airnow.gov/activity-guides.
Generally speaking, they involve limiting outdoor activities, especially prolonged outdoor exertion.