Partly Cloudy

How is the air quality in Asheville? 

When you compare the air quality in Asheville with other nearby cities that monitor the same pollutants, the air quality here is better than it is in Atlanta, Charlotte, Knoxville, and Raleigh, and it is comparable to similar size cities, such as Hickory, NC, Roanoke, VA, and Chattanooga, TN. Below is a chart comparing the Air Quality Indexes (AQI) of several monitoring sites around the region. (Click here for a detailed definition of AQI). If you would like to compare the air quality in Asheville to other areas, click here.

Data For 2009-2011 Percentage of Days that AQI was: AQI Value
Core Based Statistical Area (CBSA) Good Moderate Unhealthy for Sensitive Groups Unhealthy Maximum Annual Average 90th Percentile
Asheville, NC 78.6% 21.0% 0.5% 0.0% 104 60
Atlanta-Sandy Springs-Marietta, GA

50.5% 41.6% 7.8% 0.2% 169 90
Charlotte-Gastonia-Concord, NC-SC 65.1% 31.6% 3.2% 0.1% 151 77
Chattanooga, TN-GA 64.1% 34.3% 1.5% 0.1% 152 68
Fayetteville, NC 79.3% 20.1% 0.6% 0.0% 127 61
Greenville, NC 86.4% 13.1% 0.5% 0.0% 114 59
Hickory-Lenoir-Morganton, NC 77.0% 22.8% 0.3% 0.0% 116 59
Kingsport-Bristol, TN-VA 47.9% 36.3% 14.4% 1.3% 200 108
Knoxville, TN 58.6% 37.0% 4.3% 0.0% 147 84
Raleigh-Cary, NC 73.2% 25.9% 0.8% 0.0% 137 67
Roanoke, VA 81.5% 18.4% 0.1% 0.0% 101 58
Spartanburg, SC 71.7% 27.4% 0.9% 0.0% 132 67

Percentage of Days when Air Quality was...

These columns indicate how the daily AQI (Air Quality Index) values for a county or CBSA were distributed among four broad categories of air quality:

  1. Good — Percentage of days in the year having an AQI value 0 through 50.
  2. Moderate — Percentage of days in the year having and AQI value 51 through 100.
  3. Unhealthy for Sensitive Groups — Percentage of days in the year having an AQI value 101 through 150.
  4. Unhealthy — Percentage of days in the year having an AQI value 151 or higher. This includes the AQI categories unhealthy, very unhealthy, and hazardous. Very few locations (about 0.3% of all U.S. counties) have any days in the very unhealthy or hazardous categories.

AQI Value

These columns provide simple statistical measures of the AQI values for a county or CBSA:

  1. Maximum — The highest daily AQI value in the 3 year period.
  2. 90th Percentile — 90 percent of daily AQI values during the year were less than or equal to the 90th percentile value (the lower the number, the better the air quality).
Data Courtesy EPA (http://www.epa.gov/airdata)