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Shenandoah 



National Park . 



National Park Service 



U.S. Department of the Interior 



AIR QUALITY RATING SYSTEM 



Shenandoah National Park is known far iti beautiful views of the valleys and mountains seen from the 

 Skyline Drive. Although the view is still spectacular on most days, the actions of our modern world have 

 taken a toll in Shenandoah as they have in other parts of the world. Some days visibility will be limited. 

 Some days the ozone level may affect the'health of visitors. On a few occasions, ozone levels have 

 exceeded the federal health standards. Because of that health factor, this advisory statement has been 

 prepared. The rating system explained below will help you determine how to plan your stay in Shenandoah 

 National Park, based on the current levels of visibility and ozone. 



RATING INDEX 



VISIBILITY 



The National Park Service has developed an Air Pollution 

 Index rating system to advise visitors of ozone levels and 

 current degrees of visibility. In Shenandoah National Park the 

 ozone and visibility ratings are monitored each day, then Park 

 visitors are advised of the ratings through signs, brochures, 

 and visitor center displays. Ozone is monitored in three 

 locations in the Park. The ozone ratings are: Low (not likely 

 to affect health). Moderate (highly sensitive people may feel 

 effects), or Unhealthy (large portion of the population will be 

 able to feel effects). The visibility ratings are measured in 

 miles (0-10, 10-30, 30 + ). Be aware that the quality of air 

 can change quickly. The posted levels reflect the last time 

 the ozone and air quality levels were monitored by the Park. 



The same sulfates that contribute to the serious acid rain 

 problem in this region also cause visibility impairment. This 

 hazy smog is noticed mainly in the summer. The haze is 

 often dense enough to prevent visitors from being able tc 

 enjoy the otherwise spectacular views from the Skyline Drive 

 and mountain peaks within the Park. Visibility levels are 

 monitored at Big Meadows. 



