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Ground-Level Ozone
Ground-Level Ozone
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Ozone is a gas that you cannot see or smell. Good ozone occurs naturally about 10 to 30 miles above the Earth's surface. It makes a protective layer in the atmosphere that shields us from the sun's harmful ultraviolet rays. Ground-level ozone is created by chemical reactions at the Earth's surface.1 Ground-level ozone forms when fuel burned in cars and trucks, power plants, factories, and other sources react with heat and sunlight. Weather conditions and sunlight intensity also play a role in forming ground-level ozone. It is one of the biggest components of smog. Ground-level ozone is more likely to reach unhealthy levels on hot sunny days in urban areas but can be carried by wind to rural areas.2 Ground-level ozone is known as bad ozone because it can cause breathing problems, especially for sensitive groups like asthmatics or the elderly.
Ground-level ozone data are available on the MiTracking data portal.
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Health
As a result of studies, we know that breathing in too much ozone can increase2,3:
- Use of asthma medication.
- Absences from school.
- Visits to the emergency room and hospital admissions.
- Premature deaths from heart and lung disease.
For more information, visit the CDC Tracking Program - Air Quality (Outdoor).
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Risk Factors
Those most likely to be affected by unhealthy levels of ozone are4:
- People who have asthma or another lung disease.
- Infants and children.
- Older adults.
- Active people of all ages who exercise or work outside.
For more information, visit the CDC Air Pollutants: Additional information on ozone and particulate matter.
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Prevention
How To Check Air Quality
- Tune in to your local TV and radio stations. Some stations provide air quality forecasts to let you know when ozone levels could be harmful to your health.
- Download the EPA AIRNow app on your smart devices for current air quality conditions
Steps To Protect Your Health
When ozone is at unhealthy levels5:
- Go to AirNow for current air quality information in your area.
- Take it easy when you're outside. For example, walk instead of run.
- Limit outdoor activity to times of day when ozone levels are lower, usually the morning or evening.
- Spend more time inside.
It is also a good idea to avoid using ozone generators that are sold as air cleaners. Scientific studies show that ozone generators do very little to remove indoor air contaminants and can harm your health.6
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Data - MiTracking
Ground Ozone MiTracking Indicators
- Days above the regulatory standard (monitored and modeled data)
MiTracking Data Can Tell Us
- The number of days with maximum 8-hour average ozone levels over the National Ambient Air Quality Standard (NAAQS). The NAAQS is the maximum amount of six air pollutants, including ozone, that are allowed under the Clean Air Act.
- An estimate of the number of people and the number of days people came in contact with ozone levels over the NAAQS.
MiTracking Data Cannot Tell Us
- The amount of ozone at specific locations.
- The amount of ozone during short periods of time.
- A specific group of people who came in contact with ozone.
- The amount of ozone one person is around.
- Amounts of other air pollutants.
- The exact air quality in areas where there are no air monitors.
Find Out More
The Michigan Department of Environment, Great Lakes, and Energy (EGLE) is responsible for collecting information on air quality from air monitoring stations located across the state. EGLE provides air quality data to the Environmental Protection Agency (EPA) which maintains these types of data from states across the country in its Air Quality System (AQS). The Centers for Disease Control and Prevention (CDC) and the EPA work together to use the AQS to create the dataset. This includes developing a system for estimating air quality in counties that do not have air monitors. Data for these counties are called "modeled data."
For more data information, visit:
- About These Data (found on the data portal after a query search)
- Metadata (Technical information about the content, quality, and context of the data)
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Learn More
Asthma Initiative of Michigan (AIM)
Centers for Disease Control and Prevention (CDC)
National Environmental Public Health Tracking (CDC Tracking)
Environmental Protection Agency (EPA)
Environmental Justice Screening and Mapping Tool (EJSCREEN)
Heart Healthy Toolkit and Research: Steps You Can Take
Overview of the Clean Air Act and Pollution
Ozone Generators that are Sold as Air Cleaners
Michigan Department of Environment, Great Lakes, and Energy (EGLE)
Air Monitoring Information: Annual Air Quality Reports
Ozone Nonattainment (Workgroups, Planning, etc.)
Michigan Department of Health and Human Services (MDHHS)
Michigan Climate and Health Adaptation Program (MICHAP)
MiTracking Air Quality (Fact Sheet)
Southeast Michigan Council of Governments
What you can do to keep the air clean on ozone action days and everyday
West Michigan Clean Air Coalition
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Citations
- EPA. Ozone pollution and your patients' health: what is ozone? https://www.epa.gov/ozone-pollution-and-your-patients-health/what-ozone. Accessed May 12, 2022.
- EPA. Ground-level Ozone Basics. https://www.epa.gov/ground-level-ozone-pollution/ground-level-ozone-basics. Accessed May 12, 2022
- Iowa Public Health Tracking. Air quality and health. https://tracking.idph.iowa.gov/Environment/Air-Quality/Air-Quality-and-Health. Accessed May 12, 2022.
- CDC. Air quality: ozone and your health. https://www.cdc.gov/air/ozone.html. Accessed May 12, 2022.
- CDC. Air quality: particle pollution. https://www.cdc.gov/air/particulate_matter.html. Accessed May 12, 2022.
- EPA. Indoor air quality: ozone generators that are sold as air cleaners. https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-are-sold-air-cleaners. Accessed May 12, 2022.