Ozone Action Day

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About Ozone Action Days

An Ozone Action Day is declared when weather conditions are likely to combine with pollution emissions to form high levels of ozone near the ground that may cause harmful health effects. People and businesses should take action to reduce emissions of ozone-causing pollutants.

Local air quality experts (usually meteorologists) use air quality computer models, weather data, measurements of pollution levels, and local experience to come with a daily air pollution forecast. When this forecast indicates that high temperatures, light winds, no rain, and/or a wind direction blowing in polluted air from another area will combine to cause ozone levels in excess of the federal standards, an Ozone Action Day is declared.

Ozone Action Day Tips:
  • Conserve electricity and set your air conditioner at a higher temperature.
  • Choose a cleaner commute -- share a ride to work or use public transportation. Bicycle or walk to errands when possible.
  • Defer use of gasoline-powered lawn and garden equipment.
  • Refuel cars and trucks after dusk.
  • Combine errands and reduce trips.
  • Limit engine idling.
  • Use household, workshop, and garden chemicals in ways that keep evaporation to a minimum, or try to delay using them when poor air quality is forecast.
Everyday Tips:
  • Conserve energy -- at home, at work, everywhere.
  • Follow gasoline refueling instructions for efficient vapor recovery. Be careful not to spill fuel and always tighten your gas cap securely.
  • Keep car, boat, and other engines tuned up according to manufacturers specification.
  • Be sure your tires are properly inflated.
  • Carpool, use public transportation, bike, or walk whenever possible.
  • Use environmentally safe paints and cleaning products whenever possible.
  • Some products that you use at your home or office are made with smog-forming chemicals that can evaporate into the air when you use them. Follow manufacturers recommendations for use and properly seal cleaners, paints, and other chemicals to prevent evaporation into the air.

For a map which states have declared today an Ozone Action Day, visit the EPA Action Day page.

Visit our Ozone pollution page, general Air Pollution information page, or the Environmental Protection Agency's website.