Ozone Questions and Answers

Ozone is a toxic air pollutant that is a concern for people's health when levels in outdoor air are high. Ozone is the principal component of the mixture of air pollutants known as "smog" that is produced from the action of sunlight on air contaminants from automobile exhausts and other sources. Ozone levels are most likely to be elevated after noon through early evening on hot, sunny days. The New York State Departments of Health (DOH) and Environmental Conservation (DEC) alert the public by issuing a Ozone Health Advisory when ozone concentrations in outdoor air are expected to be unhealthy for sensitive groups.

  1. What will happen to me if I am exposed to ozone during an advisory?
    • People exposed to elevated levels of ozone may experience a variety of symptoms. The most common symptom is a feeling of irritation in the eyes, nose and throat. Some people may also experience respiratory or heart symptoms such as shortness of breath, chest pain, and wheezing. Even without such symptoms, people exposed to ozone may have changes in their lung function that can last for several days before returning to normal. Some people experience these effects as "feeling tired" or "lacking energy."
  2. When would I most likely experience these effects?
    • Ozone levels are usually highest after noon and through early evening hours on hot, sunny days, and therefore this part of the day is the peak time for symptoms. Performing vigorous exercise outdoors such as running also makes a person more likely to experience symptoms from exposure to ozone.
  3. Are some people more susceptible than others to the effects of ozone?
    • Although all individuals may be affected by ozone exposure, some people may be more sensitive than others. Young children, the elderly, people with pre-existing lung disease such as asthma and people with pre-existing heart disease or high blood pressure may be more seriously affected during an ozone advisory. Therefore, it is very important that these individuals reduce their exposure during an advisory.
  4. What can I do to reduce my exposure during an ozone advisory?
    • There are several steps that individuals can take. Whenever possible, try to limit outdoor activities during peak ozone hours. Schedule outdoor exercise or activities for the morning hours when ozone levels are generally lower. Staying indoors may help, since indoor ozone levels tend to be lower than outdoor levels. Ozone advisories are issued based on predicted ozone levels and there may be days when ozone levels rise higher than were forecast. Individuals can reduce their exposure to ozone by adjusting their outdoor activity schedules when weather conditions favor ozone production, whether or not an advisory has been issued. Individuals should consider consulting their physician if they experience a worsening of their respiratory or heart symptoms.
  5. How will I know that I may be exposed to high levels of ozone?
    • The New York State Department Environmental Conservation informs the public whenever ozone concentrations in outdoor air are expected to be elevated. Every weekday morning during the May - September ozone season the Department of Environmental Conservation will review weather conditions and data from their air monitoring stations to determine if, for that day or the following day, ozone levels are expected to exceed the standard of 0.075 parts per million averaged over eight hours. If it is likely that this level will be exceeded, the agency will contact the media so that the advisory can be carried on afternoon and evening broadcasts. The Department of Environmental Conservation also provides ozone monitoring data and ozone forecasts on its Ozone web site. Since forecasting may not always accurately predict the need for an advisory, keep in mind that hot, sunny days, especially days with little or no wind, may foster higher ozone levels.
  6. Who can I contact if I have more questions?
    • If you would like additional information on the health effects of ozone, you can call the Department of Health Environmental Hotline toll-free at 1-800-458-1158. To find out if an advisory has been issued or to learn more about air quality, you can call the Department of Environmental Conservation's toll-free air quality hotline: 1-800-535-1345 or visit their Air Quality Index (AQI) Forecast web page where you can also view state ozone maps and real-time monitoring data for ozone.