Chicago's air quality reached slightly elevated levels Wednesday, but why did that happen and how bad was it?
As of Wednesday afternoon, the air quality level sat at "moderate," with a PM2.5 of 70.
"If you are unusually sensitive to particle pollution, consider reducing your activity level or shorten the amount of time you are active outdoors," the government air quality website AirNow reported.
The level isn't unusually high for the city, but it is higher than "good." And projections show it is expected to stay in the moderate range through Thursday.
So why is it elevated?
While no exact reason was given, NBC 5 Meteorologist Kevin Jeanes said iIt’s not smoke or high levels of ozone like we can get in warmer months."
"It may just be from common combustible air pollution that’s creating slightly higher levels of PM2.5," Jeanes said, noting uncertainty surrounding the topic. "The air has also been pretty stagnant lately with fog nearly every morning."
Weather
But things could improve soon.
"We have a windy day coming Thursday along with the chance of rain, so that should improve the air quality," he said.
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To check the air quality level in your area right now, click here.
PM2.5 is an air pollutant also known as fine particulate matter.
In total, there are six categories: green, or good; yellow, or moderate; orange, or unhealthy for sensitive groups; red, or unhealthy; purple, or very unhealthy; and maroon, or hazardous.
| Daily AQI Color | Levels of Concern | Values of Index | Description of Air Quality |
|---|---|---|---|
| Green | Good | 0 to 50 | Air quality is satisfactory, and air pollution poses little or no risk. |
| Yellow | Moderate | 51 to 100 | Air quality is acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution. |
| Orange | Unhealthy for Sensitive Groups | 101 to 150 | Members of sensitive groups may experience health effects. The general public is less likely to be affected. |
| Red | Unhealthy | 151 to 200 | Some members of the general public may experience health effects; members of sensitive groups may experience more serious health effects. |
| Purple | Very Unhealthy | 201 to 300 | Health alert: The risk of health effects is increased for everyone. |
| Maroon | Hazardous | 301 and higher | Health warning of emergency conditions: everyone is more likely to be affected. |
