PM2.5 Design Values for 1999-2001 in NC Counties

A map of estimated annual mean PM2.5 in 24 hour concentrations for January 1999 through December 2001.


Figure 1 Annual Design Values (Mean) (click for larger image)

Table 1. The following table shows 11 counties with a 3-year average of the annual mean PM2.5 for each year below the established standard. The first column lists the county; the second lists the average value for that county. Some entries have an additional comment indicating the design value given is based on incomplete data.

County Average value Additional comment
Alamance 14.6 µg/m3  
Buncombe 14.4 µg/m3 at least one calendar quarter was not valid
Caswell 14.5 µg/m3 at least one calendar quarter was not valid
Chatham 13.4 µg/m3 at least one calendar quarter was not valid
Duplin 12.6 µg/m3  
Lenoir 12.3 µg/m3  
New Hanover 12.2 µg/m3  
Onslow 12.1 µg/m3  
Orange 14.3 µg/m3  
Pitt 13.7 µg/m3 at least one calendar quarter was not valid
Swain 14.1 µg/m3  

Table 2. The following table shows 14 counties with a 3-year average of the annual mean PM2.5 for each year above the established standard. The first column lists the county; the second lists the average value for that county. Some entries have an additional comment indicating the design value given is based on incomplete data.

Note: Nonattainment designations may not follow county boundaries and will be based on later data than are shown in this table.

County Average value Additional comment
Cabarrus 15.6 µg/m3  
Catawba 17.0 µg/m3 at least one calendar quarter was not valid
Cumberland 15.4 µg/m3  
Davidson 17.3 µg/m3 at least one calendar quarter was not valid
Durham 15.3 µg/m3  
Forsyth 16.1 µg/m3  
Gaston 15.3 µg/m3  
Guilford 16.3 µg/m3  
Haywood 15.2 µg/m3  
McDowell 15.8 µg/m3  
Mecklenburg 16.6 µg/m3  
Mitchell 15.3 µg/m3  
Wake 15.3 µg/m3  
Wayne 15.3 µg/m3  

Table 3. The following table shows 6 counties that were monitored in 2001 but did not have enough historical data to calculate a valid 3-year average of the annual mean PM2.5 that could be compared to the established standard.

County Average value
Edgecombe N/A µg/m3
Jackson N/A µg/m3
Montgomery N/A µg/m3
Pasquotank N/A µg/m3
Robeson N/A µg/m3
Watauga N/A µg/m3