The Missouri Department of Natural Resources monitors ozone across the state during the ozone season, which begins April 1 and ends Oct. 31. Naturally occurring ozone in the upper atmosphere protects the earth from the sun's harmful rays. Ground-level ozone, commonly known as smog, is a gas that is created when pollution from vehicles, businesses and power plants combine in the presence of sunlight. The pollutant is formed when heat and sunlight mix with Volatile Organic Compounds, or VOCs, and nitrogen oxides, or NOx, in the lower atmosphere. Typically, ozone pollution is more of a problem in the hot summer months because sunlight and warm temperatures speed up the formation of ground-level ozone.
Exposure to ground-level ozone can contribute to health and environmental problems. Ground-level ozone is an irritant that damages lung tissue and aggravates respiratory disease. Ozone can trigger a variety of health problems. Those most susceptible to ozone include children, the elderly and individuals with pre-existing respiratory problems. Children are at increased risk from exposure to ground-level ozone because their lungs are still developing. Healthy adults can experience problems breathing, especially those who exercise or work outdoors.
Simple everyday steps can help reduce the emission of harmful pollutants that are derived from vehicles and coal-fired power plants that produce our energy. These emissions contribute to the formation of ground-level ozone.
Ozone-reducing activities include:
- Keep tires properly inflated.
- Use mass transit, carpool, bike or walk.
- Do not top off gas tanks. Stop at the first click.
- Do not use gas-powered lawn equipment on hot, sunny days with little or no wind. Consider waiting until early evening to mow your lawn.
- Conserve energy by turning off lights and appliances when leaving a room to reduce emissions from power plants. Purchase Energy Star® appliances.
- Set goals to reduce utility bills by two percent. This can save money and protect air quality.
The department maintains and collects data from air monitors across Missouri to see if Missouri’s air quality meets the Environmental Protection Agency’s National Ambient Air Quality Standards. If an area monitors or contributes to violations of the ozone standard, actions must be taken to reduce the emissions that contribute to the formation of ground-level ozone. The department works with affected areas to develop emission reducing measures that are the most effective in terms of cost and emission reductions.
Ozone Monitoring Data
- Missouri Air Quality Data System. Today's Ozone Levels
- Summary of Monitored Ozone Values.
Preliminary 1-hour O3 parts per million, CST.
Preliminary 8-hour O3 parts per million, CST.
- Revised 2008 8-Hour Ozone Standard Boundary Recommendation
- Original 2008 8-Hour Ozone Standard Boundary Recommendation
On Sept. 22, 2011, the U.S. Environmental Protection Agency released a memorandum to clarify for states the status of the 2008 Ozone National Ambient Air Quality Standard. In this document, EPA explicitly stated that the current standard is 0.075 parts per million, or 75 parts per billion. EPA also announced their intentions to move forward with designations under the 2008 National Ambient Air Quality Standard, starting with the recommendations made by states in 2009, and then updating them with the most current, certified air quality data from the 2008 to 2010 monitoring period.
- 1997 Boundary Designations
Missouri Response to EPA Letters Dated Dec. 4 and 12, 2003 (02/04)
Eight-Hour Ozone Designation EPA Response Letter for Missouri
- State Implementation Plans for Ozone
Ozone State Implementation Plan
Other Ozone Links
APCP Calendar of Events
The Darker Side of Ozone
EPA Ozone webpage
Help fight ozone this summer!
Kansas City AirQ - Kansas City Air Quality Forecast
Missouri Air Quality Monitoring Network
Other Environmental Links
Ozone - Something you can easily reduce!
St. Louis Regional Clean Air Partnership - St. Louis Air Quality Forecast