Strong ozone alert for 8 WI lakeshore counties

You don't often see ozone alerts issues in the "red" category, but that's what's going on from Door County south to the IL border right now. The air quality is considered unhealthy for everyone and not just for people in so-called higher-risk categories. Not a good day for outdoor activities. 

Advisory for Ozone (Red)

Start Time:	1:54PM CT Saturday, July 25, 2020
End Time:	11:00PM CT Saturday, July 25, 2020
Counties:	Door, Kenosha, Kewaunee, Manitowoc, Milwaukee, Ozaukee, Racine, Sheboygan

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AIR QUALITY INDEX CHART

Air Quality Index (AQI) Values	Levels of Health Concern	Colors
When the AQI is in this range:	...air quality conditions are:	...as symbolized by this color:
0 to 50	Good	Green
51 to 100	Moderate	Yellow
101 to 150	Unhealthy for Sensitive Groups	Orange
151 to 200	Unhealthy	Red
201 to 300	Very Unhealthy	Purple
301 to 500	Hazardous	Maroon

For More Information:

• Detailed Alert Status Information

• Air Quality Index

• Do a little, save a lot!

• Local DNR air management program contacts

Wisconsin's Current Air Quality

What is ozone?

Ozone is a gas composed of three atoms of oxygen. Ozone occurs both in the Earth's upper atmosphere and at ground level. Ozone can be good or bad, depending on where it is found: 

· Good Ozone. Ozone occurs naturally in the Earth's upper atmosphere - 6 to 30 miles above the Earth's surface - where it forms a protective layer that shields us from the sun's harmful ultraviolet rays. Manmade chemicals are known to destroy this beneficial ozone. An area where the protective "ozone layer" has been significantly depleted-for example, over the North or South pole-is sometimes called "the ozone hole." The United States, along with over 180 other countries, recognized the threats posed by ozone depletion and in 1987 adopted a treaty called the Montreal Protocol to phase out the production and use of ozone-depleting substances. EPA has established regulations to phase out ozone-depleting chemicals in the United States. Learn more 

· Bad Ozone. In the Earth's lower atmosphere, near ground level, ozone is formed when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources react chemically in the presence of sunlight. 

Ozone at ground level is a harmful air pollutant.For more information on ozone, please see https://epa.gov/ozone-pollution

Also, the EPA posts this information - and pay attention to the "unhealthy" category, which is red on the chart and covers the WI lakeshore counties. I will italicize it:

 "Unhealthy for Sensitive Groups" (101 - 150) When air quality is in this range, people that are included in a sensitive group, whether the sensitivity is due to medical conditions, exposure conditions, or inherent susceptibility, may experience the effects described above when engaged in outdoor activities. However, exposures to ambient concentrations in this range are not likely to result in effects in the general population. For ozone, the sensitive group includes children; people with lung diseases, such as asthma, chronic bronchitis, and emphysema; older adults; and active people who work or exercise outdoors. EPA's risk assessment (Whitfield et al., 1996) indicates that at this level for healthy individuals (adults and children) at moderate exertion: 1) approximately 18% are estimated to experience moderate or greater lung function impairment, 2) approximately 9% are estimated to experience large or greater lung function impairments, and 3) approximately 2% are estimated to experience moderate to severe aggravated cough. 

 "Unhealthy" (151 - 200) When air quality is in this range, any individual who is active outdoors may experience the respiratory effects described above. Members of sensitive groups are likely to experience more severe effects. EPA's risk assessment (Whitfield et al., 1996) indicates that at this level for healthy individuals (adults and children) at moderate exertion: 1) approximately 30% are estimated to experience moderate or greater lung function impairment, 2) approximately 15% are estimated to experience large or greater lung function impairments, and 3) approximately 5% are estimated to experience moderate to severe respiratory symptoms (i.e., chest pain with deep inspiration and aggravated cough).