The American Lung Association is sending the Door Peninsula to the principal’s office for its poor grades in its most recent State of the Air report card. The organization looks at the number of days a county’s air reaches unhealthy levels on the Air Quality Index for ozone and puts those days on a weighted scale for days that are unhealthy for sensitive groups (orange), unhealthy (red), very unhealthy (purple), and hazardous (maroon). Based on data collected from 26 counties, Door County was one of seven counties with a failing grade, and Kewaunee County was one of three counties with a D grade. Only nine of the 26 reported counties received a grade of B or greater. Over the last three years, Door County had 12 orange ozone days, and Kewaunee County had five orange ozone days and one red. The State of the Air report card did not collect particle pollution data for its study.

Despite the low ratings now, it is a far cry from what was when Door County's weighted annual average, which covers a three-year time, stood at nearly 24 ozone days between 1997-1999. In fact, it did not dip below 15 ozone days until 2006-2008. Now, Door County's weighted annual average hovers around five ozone days over a three-year time period, which is where it has been since 2006-2008.

Poor air quality in northeast Wisconsin is attributed to local factors. Its location is downwind from Milwaukee and Chicago, where more pollution is produced. In 2022, the Door County area was formally redesignated to attain the 2015 National Ambient Air Quality Standard for ground-level ozone, meeting a recent national standard set to protect public health. 

This article previously and accidentally excluded the term weighted annual average, which takes the number of ozone action days over the course of three years.