The table below shows current air quality concentrations at New Hampshire's air monitoring sites for two air pollutants: ground-level ozone and particle pollution (fine particles).  Full monitoring, reporting, and forecasting for ozone occurs from April through September; monitoring and reporting of fine particles occurs year-round. The information in the table is updated every hour and includes wind speed, wind direction, and outside temperatures (if data are available). A map of monitoring site locations is shown at the right. DES operates the majority of these sites and regularly monitors data quality. The University of New Hampshire operates additional sites as part of their AIRMAP program, the Appalachian Mountain Club (AMC) maintains three monitors in northern New Hampshire, and the Hubbard Brook Research Foundation (HBRF) maintains one station in cooperation with the EPA. The data from HBRF may be downloaded from CASTNET. The table and map are color coded according to EPA's Air Quality Index, which relates air pollutant concentrations to health effects and recommended actions. Health Guide and Recommended Actions

Map of Current Air Quality (Ozone and Fine Particles)

Relative Pollutant Levels Chart Comparison

Ozone and Fine Particles Real-Time Monitoring Data Placing your cursor over the table cell displays the health message; Clicking on the table cell displays a graph of pollutant levels over the previous 48 hours. Site Location 8-hour Ozone (ppb) 24-hour Fine Particles (ug/m3) Wind Speed and Direction Temp. Concord - DES 18   NNW @ 2 mph 71o F Keene - DES 17 3 NW @ 7 mph 73o F Laconia - DES 24   ESE @ 1 mph 69o F Lebanon Airport - DES 15 7 N @ 4 mph 66o F Lincoln/Woodstock   (Hubbard Brook Experimental Forest) - EPA 19     71o F Londonderry - DES 20 8 NNW @ 4 mph 69o F Mount Washington Base - DES/AMC 19       Nashua - DES 22   N @ 4 mph 75o F Portsmouth (Pierce Island) - DES 22 9 E @ 3 mph 70o F Seacoast (Odiorne State Park, Rye) - DES 22   ENE @ 10 mph 67o F   High Elevation Site Location 8-hour Ozone (ppb) 24-hour Fine Particles (ug/m3) Wind Speed and Direction Temp. Miller State Park (Southern Mountains) - DES 34 13 SSW @ 5 mph 60o F Mount Washington Summit   (Northern Mountains) - DES/AMC 38     47o F Sulfur Dioxide Real-Time Monitoring Data Site Location 1-hour Sulfur Dioxide (ppb) Wind Speed and Direction Temp. Concord - DES 0 NNW @ 2 mph 71o F Londonderry - DES 0 NNW @ 4 mph 69o F Miller State Park (Southern Mountains) - DES 1 SSW @ 5 mph 60o F Pembroke- DES 0 W @ 1 mph 74o F Portsmouth (Pierce Island) - DES 0 E @ 3 mph 70o F NOTES:   1.   Ozone values are based on eight-hour running averages;  Fine Particle values are based on twenty four-hour running averages.   If a complete-period average cannot be calculated, due to absence of data, the average is displayed within square brackets (e.g., [ 31 ]) 2.   Data in the table are based on real-time hourly averages for the time period ending:  11 am 6/19/2013 EST.   All real-time values are unofficial pending full quality assurance/quality control evaluation. 3.   Sulfur Dioxide (SO2), Wind Speed, Wind Direction, and Temperature values are based on the latest one-hour average. 4.   N/D indicates that the Site is enabled but the lastest-period data are temporarily unavailable. 5.   N/R indicates that the Site is currently disabled. 6.   Grayed-out cells indicate that the parameter is not collected at the Site. 7.   Seasonal indicates that Ozone monitoring occurs from April through September at the site.

Ground-level Ozone
Ground-level ozone, more commonly called smog, is measured in parts per billion (ppb). The federal health based standard for an 8-hour concentration is set at 75 ppb. Since ozone is a summertime pollutant, wintertime monitoring is limited and no wintertime forecast is provided. Full monitoring, reporting, and forecasting for ozone occurs from April through September.

The EPA established a tighter 8-hour ozone standard in March of 2008 to better protect public health. The 8-hour standard was lowered from 0.08 ppm to 0.075 ppm. For more information, please visit www.epa.gov/groundlevelozone/.

Fine Particles
Fine particle pollution consists of both solid and liquid particles that are less than 2.5 microns in diameter (a micron is a millionth of a meter). Particle concentrations are measured in micrograms per cubic meter (ug/m³). The federal health based standard for a 24-hour concentration is set at 35 ug/m³. Monitoring and reporting of fine particles occurs year-round.

The EPA established a tighter daily fine particles standard in the fall of 2006 to better protect public health. The daily standard was lowered from 65 ug/m³ to 35 ug/m³. For more information, please visit www.epa.gov/air/particles/.

Sulfur Dioxide
Sulfur dioxide (SO₂) is a highly reactive gas which primarily comes from fossil fuel combustion at power plants and other industrial facilities. Sulfur dioxide concentrations are measured in parts per billion (ppb). The federal health based standard for 1-hour concentrations is set at 75 ppb. Monitoring and reporting of sulfur dioxide occurs year round.

EPA first set standards for sulfur dioxide in 1971. In June 2010 EPA established a 1-hour SO₂ standard at 75 ppb to better protect public health. For more information, please visit www.epa.gov/airquality/sulfurdioxide.

Related Topics

• Daily Air Quality Forecast
• Pollen Counts
• UV Index