Hazardous air quality conditions in part of metro Detroit, index shows

The air quality in Detroit is unhealthy Friday with some areas in southeast Michigan even experiencing very unhealthy or hazardous conditions, according to the U.S. Air Quality Index.

People with heart or lung disease, older adults, children and teens in those areas should avoid physical activities outdoors. All others should avoid strenuous outdoor activities and keep outdoor activities short.

Although Michigan's ozone season generally runs between the warmer months of March and October, particle pollution from sources like power plants, vehicle emissions and industry can reach unhealthy levels year-round. Some of these pollutants are so small, PM2.5, they can be inhaled into your lungs and can even enter your bloodstream with serious health consequences. Other sources of particle pollution include unpaved roads, construction sites and wildfire smoke, like the spate of unhealthy air days Michiganders experienced in the summer of 2023 when Canadian wildfires darkened Detroit's skyline.

Michigan's current air quality

The map below displays the current air quality at monitoring sites in the U.S., Canada and Mexico. Air monitoring sites are color-coded based on the pollutant (ozone or particulate matter) with the highest value. Particles that are less than 10 micrometers and 2.5 micrometers in diameter are called PM10 and PM2.5, respectively.

An AQI of 50 or below means the current air quality is good. The shaded areas of the map show the approximate boundaries where air quality is available and listed as anything other than good. The information is updated hourly.

Air Quality Index guidelines (ozone and particle pollution)

Some people are more sensitive to air pollution because of their age or health. People who are active or work outdoors are also at higher risk when the air quality is poor. Health concerns related to poor air quality may include difficulty breathing, coughing or wheezing and more serious health effects such as lung damage, asthma attacks, heart attacks and stroke.

Here's how to interpret the Air Quality Index values, according to the U.S. EPA:

• Good (0-50): The level of pollution in the air is of little to no risk.
• Moderate (51-100): For people who are unusually sensitive to air pollution, a moderate health concern may exist.
• Unhealthy for sensitive groups (101-150): People who are more sensitive to air pollution may experience health effects. The general public is not likely to be affected.
• Unhealthy (151-200): Some people may begin to experience health effects; members of sensitive groups may experience more serious health effects.
• Very unhealthy (201-300): An alert is triggered; the general population is at risk for more serious health effects.
• Hazardous (301-500): Emergency conditions health alert: Everyone is likely to be affected.

For more information about air quality, visit AirNow.gov.

Kristi Tanner is a data reporter. Contact her at ktanner@freepress.com. Follow her on Twitter: @midatalove.

Free Press reporter Kylie Martin contributed to this report.