Ozone

Ozone is a gas that occurs in both Earth’s upper atmosphere and at ground level. When ozone is at ground level, it is a major component in smog and can cause a number of health problems for humans and other living things. Because of this serious health risk, the Air Management Program monitors ground-level ozone around the state and issues watches and advisories when levels become potentially harmful. Several eastern Wisconsin counties have not met federal clean air standards for ozone in the past, requiring businesses and residents in those areas to take special measures to reduce ground-level ozone.

The following pages provide information for residents, businesses, educators, journalists and others looking for more about ozone’s health effects, air quality watches and advisories, state and federal regulations, and monitoring data and other resources.

• Ozone Basics and Health Effects
  Basic information about how ground-level ozone forms and its negative effects on human health, along with educational resources for adults and K-12
• Air Quality Watches & Advisories
  Updates on issued watches and advisories, background on the watch/advisory program and links to sign up for e-mail alerts
• Standards and Nonattainment Designations
  Overview of federal and state ozone standards and info on "nonattainment" designations for areas with harmful ozone levels
• Control Strategies and Regulations
  Information on specific programs to control ozone, including links to pages on mobile sources, interstate transportation and voluntary ozone reduction programs
• Resources and Air Monitoring Data
  Links to current and historical air monitoring data, publications and other ozone-related resources