Ozone Health Advisories Issued for National Parks
Today – Monday, September 22, 2008
Currently, no national parks are issuing ozone health advisories.
Ozone is an air pollutant produced from human-caused emissions that reacts in sunlight. High concentrations of ozone can cause inflammation and irritation of the respiratory tract, particularly during heavy physical activity. Ozone concentrations have approached and exceeded the national health standards at several National Park Service areas. Because of possible health effects and concern for the health and safety of visitors and employees, the National Park Service developed guidance for ozone advisory programs in National Park Service units where levels approach or exceed the ozone health standard (75 parts per billion, 8-hour average). These parks include Acadia NP, Great Smoky Mountains NP, Mammoth Cave NP, Rocky Mountain NP, Sequoia/Kings Canyon NPs, and Shenandoah NP. Whenever ozone levels exceed or are predicted to exceed this health standard at these parks, the park personnel post health advisories cautioning visitors of the potential health risks associated with exposures to elevated levels.
National Park Service Ozone Health Advisory Levels
| Ozone Value | Descriptor | Group Notified |
|---|---|---|
| 0 – 59 ppb | Good | None |
| 60 – 75 ppb | Moderate | None |
| 76 – 95 ppb | Unhealthy for Sensitive Groups |
Sensitive Groups
Above 75 ppb for an 8-hour average, children, the elderly, and people with respiratory problems should reduce outdoor activities |
| 96 – 114 ppb | Unhealthy for the General Public | General Public
Above 95 ppb for an 8-hour average, active children and adults should reduce outdoor activities |
| 115 ppb or greater | Very Unhealthy for the General Public | General Public
At or above 115 ppb for an 8-hour average, everyone should reduce outdoor activities |