PM2.5 Design Values for 2002-2004 in NC Counties
There are two counties with a 3-year average of the annual mean PM2.5 above the annual standard, but no counties with a 3-year average of the 98thpercentile above the daily standard.
Figure 1 Annual Design Values (Mean) (click for larger image)
Figure 2 Daily Design Values (98th %) (click for larger image)
Table 1. The following table shows 29 counties with a 3-year average of the annual mean PM2.5 for each year below the established annual standard and 29 counties with 3-year averages for the 98th percentile of PM2.5 concentrations below the established daily standard. The first column lists the county; the second lists the average value for that county (rounded to the specifications of the annual standard); the third lists the average 98th percentile value for that county (rounded to the specifications of the daily standard). In Counties with more than one PM2.5 monitoring site, the value reported is the highest 3-year average among the inclusive sites. Averages for the counties marked with an asterisk are "unofficial estimates", because a sample size requirement (data completeness) was not satisfied.
| County | Average value | Average 98th Percentile |
|---|---|---|
| Alamance | 13.7 µg/m3 | 30 µg/m3 |
| Buncombe | 12.9 µg/m3 | 29 µg/m3 |
| Cabarrus | 14.5 µg/m3 | 32 µg/m3 |
| Caswell | 13.1 µg/m3 | 30 µg/m3 |
| Catawba | (see Table 2) | 34 µg/m3 |
| Chatham | 12.0 µg/m3 | 26 µg/m3 |
| Cumberland | 13.8 µg/m3 | 32 µg/m3 |
| Davidson | (see Table 2) | 33 µg/m3 |
| Duplin | 11.8 µg/m3 | 27 µg/m3 |
| Durham | 13.6 µg/m3 | 33 µg/m3 |
| Edgecombe | 11.6 µg/m3 | n/a |
| Forsyth | 14.3 µg/m3 | 33 µg/m3 |
| Gaston | 14.1 µg/m3 | 30 µg/m3 |
| Guilford | 13.7 µg/m3 | 31 µg/m3 |
| Haywood | 12.9 µg/m3 | 27 µg/m3 |
| Jackson | 11.9 µg/m3 | 26 µg/m3 |
| Lenoir | 11.2 µg/m3 | 26 µg/m3 |
| McDowell | 13.9 µg/m3 | 29 µg/m3 |
| Martin | 11.3 µg/m3 | n/a |
| Mecklenburg | 14.9 µg/m3 | 32 µg/m3 |
| Mitchell | 12.8 µg/m3 | 28 µg/m3 |
| Montgomery | 12.1 µg/m3 | 26 µg/m3 |
| New Hanover * | 9.9 µg/m3 | 23 µg/m3 |
| Onslow | 11.2 µg/m3 | 24 µg/m3 |
| Orange | 13.0 µg/m3 | 28 µg/m3 |
| Pitt | 12.1 µg/m3 | 28 µg/m3 |
| Robeson | 12.6 µg/m3 | 28 µg/m3 |
| Swain | 12.4 µg/m3 | 26 µg/m3 |
| Wake | 13.5 µg/m3 | 32 µg/m3 |
| Watauga | 11.6 µg/m3 | 30 µg/m3 |
| Wayne | 13.2 µg/m3 | 28 µg/m3 |
Table 2. The following table shows 2 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.
Note:
- Additional counties may be involved in emission reduction strategies
- Nonattainment designations may not follow county boundaries
| County | Average value |
|---|---|
| Catawba | 15.1 µg/m3 |
| Davidson | 15.4 µg/m3 |