On March 8, 2000 the Great Smoky Mountains National Park experienced its first bad air day of the year 2000. This is the earliest the Park has recorded a high ozone level. Ozone monitors at Look Rock and Cove Mountain registering elevated ground-level ozone levels as high as 100 parts per billion over a period of eight hours.

The Smokies' Cove Mountain monitoring station measured 96 ppb over an eight-hour period March 8. The Park's Look Rock station measured 91 ppb, with a one-hour high of 101 ppg.

Measurements above 85 parts per billion are considered unhealthy, especially for the young, the old and those with respiratory problems. Amounts over 105 ppb are considered unhealthy for everyone.

In 1999, the Great Smoky Mountains National Park experienced a record 54 days when ozone levels exceeded safety standards. The latest ozone exceedance day ever recorded occurred last year on Oct. 29.

There has been year round monitoring in the Park the past 10 years.