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Ozone Average Values

NC Counties Meeting the Ozone Standard: 2013-2015

Please click here to open the Ozone Values Map as a PDF.

Ozone monitoring sites are located in 31 North Carolina counties and operated by state, local, federal and Tribal Governments.  For Ozone, the United States Environmental Protection Agency (USEPA) defines the Design Value as the 4th highest daily maximum 8-hour average concentration, averaged over a 3-year period.  The current USEPA standard for Ozone is .070 parts per million, or ppm.  Any design value above this level is considered non-attainment of the standard.  There are currently no counties in North Carolina in non-attainment.  The table below shows the 4th highest 8- hour average recorded in each county, where a monitor is located, during the last 3-year period.  The first column lists the county, the second column lists the average mean ozone concentration for the period, and the third column lists the 4th highest 8-hour maximum average recorded.  For counties with more than one monitoring site, the value reported is the highest among the inclusive sites. 

County   Mean Design Value

Alexander [1] 

47  

64

Avery [4]         

48          

64

Buncombe [1] 

46           

62

Caldwell [1]      

49           

64

Carteret [4]        

44             

58

Caswell [2]         

47              

61

Cumberland [1]  

48               

63

Durham [1]           

47                

61

Edgecombe [1]      

46                 

62

Forsyth [1]               

51                  

67

Graham [2]              

48                   

63

Granville [1]

49                    

64

Guilford [1]   

51                     

65

Haywood [2]  

50                       

64

Johnston [1]    

46                        

63

Lee [2]               

47                         

61

Lenoir [1]           

45                          

62

Lincoln [1]           

49  

67

Macon [4]   

43    

61

Martin [1]    

42     

60

Mecklenburg [1]

51      

70

Montgomery [4] 

46       

60

New Hanover [1] 

44        

58

Person [1]              

48         

61

Pitt [1]                     

46          

62

Rockingham [1]      

49          

65

Rowan [2]                 

48            

64

Swain [1]                    

44             

60

Union [2]               

49              

67

Wake [3]                 

44               

66

Yancey [1]                

51                 

65

 Purpose of Monitor

[1] SLAMS – (State and Local Monitoring Stations) Network of monitoring stations that monitor ambient air concentrations for pollutants for which standards have been established. The scale of these sites can be either neighborhood or urban.

 [2] SPM – (Special Purpose Monitors) SPMs allow the capability of providing monitoring for various reasons such as special studies, modeling verification or compliance status, and other objectives. These monitors are not committed to any one location or for any specified period.

[3] NCORE – (National Core) Community-oriented multi-pollutant monitoring station used to evaluate the regional air quality models used in developing emission strategies and to track trends in air pollution abatement control measures’ impact on improving air quality.

[4] CastNet – (Clean Air Status and Trends Network)- federally operated sites used to evaluate the effectiveness of regional and national control programs for compliance with the NAAQS Ozone Standard.

2013-2015

2013-2015

NC Counties Meeting the Ozone Standard: 2013-2015

 

Please click here to open the Ozone Values Map as a PDF.

 

Table 1. The following table shows the 3-year averages for ozone. The first column lists the county, the second column lists the average value for that county. The current 8-hr ozone standard is 0.070 ppm.


County 2013-2015 Average Value
Alexander 0.064 ppm
Avery 0.062 ppm
Buncombe 0.063 ppm
Caldwell 0.062 ppm
Carteret 0.060 ppm
Caswell 0.063 ppm
Chatham 0.058 ppm
Cumberland 0.061 ppm
Durham 0.061 ppm
Edgecombe 0.062 ppm
Forsyth 0.067 ppm
Franklin 0.061 ppm
Graham 0.064 ppm
Granville 0.063 ppm
Guilford 0.063 ppm
Haywood 0.065 ppm
Johnston 0.063 ppm
Lee 0.055 ppm
Lenoir 0.063 ppm
Lincoln 0.065 ppm
Macon 0.062 ppm
Martin 0.062 ppm
Mecklenburg 0.068 ppm
Montgomery 0.060 ppm
New Hanover 0.061 ppm
Person 0.061 ppm
Pitt 0.062 ppm
Rockingham 0.064 ppm
Rowan 0.064 ppm
Swain 0.057 ppm
Union 0.065 ppm
Wake 0.063 ppm
Yancey 0.063 ppm