With hot and humid conditions expected to persist in the Chicago area for several more days, the Illinois Environmental Protection Agency has declared that Friday will be an air pollution action day in the greater metropolitan area.
According to a press release, the pollution alert will go into effect at midnight and will expire in 24 hours.
Officials say an air pollution action day is declared when weather conditions lead to ozone and airborne particulate levels that are considered to be above safe levels for sensitive groups.
Active children and adults who have pulmonary or respiratory diseases, such as asthma, are encouraged to avoid prolonged activity outdoors during the alert, according to officials.
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When ozone or airborne particulate levels are elevated, residents are encouraged to skip outdoor chores like mowing lawns. Reducing vehicle trips and limiting engine idling are encouraged, as are avoiding burns or other activities that send pollutants into the air.