National Ambient Air Quality Standards

Carbon monoxide is a colorless, odorless, and (at much higher levels) poisonous gas, formed when carbon in fuels is not burned completely. It is a product of motor vehicle exhaust, which contributes about 60 percent of all CO emissions nationwide. High concentrations of CO generally occur in areas with heavy traffic congestion. In cities, as much as 95 percent of all CO emissions may emanate from automobile exhaust. Other sources of CO emissions include industrial processes such as carbon black manufacturing, non-transportation fuel combustion, and natural sources such as wildfires. Woodstoves, cooking, cigarette smoke, and space heating are sources of CO in indoor environments. Peak CO concentrations typically occur during the colder months of the year when CO automotive emissions are greater and nighttime inversion conditions are more frequent.  

 

All areas of West Virginia are in attainment with the carbon monoxide NAAQS. For more information see the U.S. EPA website.  

• EPA: Carbon Monoxide (CO) Pollution in Outdoor Air

 

Lead is a metal found naturally in the environment as well as in manufactured products. The major sources of lead emissions have historically been from fuels in motor vehicles (such as cars and trucks) and industrial sources. Emissions from on-road vehicles decreased 99% between 1970 and 1995 due primarily to the use of unleaded gasoline. Use of leaded gasoline in highway vehicles was prohibited on December 31, 1995. Due to the phase out of leaded gasoline, ore and metals processing is the major source of lead emissions to the air today.  

The highest levels of lead in air are generally found near lead smelters. Other stationary sources are waste incinerators, utilities, and lead-acid battery manufacturers. Combustion and smelting processes operate at high temperatures and emit submicron particulate matter lead. Material handling and mechanical operations emit larger particles of lead.  

 

All areas of West Virginia are in attainment with the lead NAAQS.  

U.S. EPA is reviewing the current lead NAAQS. For more information see the EPA website.  

• EPA: Lead (Pb) Air Pollution

 

Nitrogen dioxide (NO₂) is one of a group of highly reactive gasses known as "oxides of nitrogen," or "nitrogen oxides (NO_x)." Other nitrogen oxides include nitrous acid and nitric acid. While EPA's National Ambient Air Quality Standard covers this entire group of NO_x, NO₂ is the component of greatest interest and the indicator for the larger group of nitrogen oxides. NO₂ forms quickly from emissions from cars, trucks and buses, power plants, and off-road equipment. In addition to contributing to the formation of ground-level ozone, and fine particle pollution, NO₂ is linked with a number of adverse effects on the respiratory system.  

EPA first set standards for NO₂ in 1971, setting both a primary standard (to protect health) and a secondary standard (to protect the public welfare) at 0.053 parts per million (53 ppb), averaged annually. The Agency has reviewed the standards twice since that time, but chose not to revise the standards at the conclusion of each review. All areas in the U.S. meet the current (1971) NO₂ standards.  

 

EPA is currently reviewing the NO₂ NAAQS. For more information see the EPA website.  

• EPA: Nitrogen Dioxide (NO₂) Pollution

 

The term "particulate matter" (PM) includes both solid particles and liquid droplets found in air. Many manmade and natural sources emit PM directly or emit other pollutants that react in the atmosphere to form PM. These solid and liquid particles come in a wide range of sizes.  

Particles less than 10 micrometers in diameter (PM₁₀) pose a health concern because they can be inhaled into and accumulate in the respiratory system Particles less than 2.5 micrometers in diameter (PM_2.5) are referred to as "fine"particles and are believed to post the largest health risks. Because of their small size, fine particles can lodge deeply into the lungs. Sources of fine particles include all types of combustion (motor vehicles, power plants, wood burning, etc.) and some industrial processes. Particles with diameters between 2.5 and 10 micrometers are referred to as "coarse." Sources of coarse particles include crushing or grinding operations, and dust from paved or unpaved roads.  

 

For more information regarding the PM₁₀ and PM_2.5 NAAQS, please see the EPA website.  

• EPA: Particulate Matter (PM) Pollution

 

1997 PM2.5 Maintenance Areas

EPA designated 6 areas (ten counties, and 2 partial counties) in West Virginia as nonattainment with respect to the 1997 PM2.5 NAAQS:  

• Charleston, WV [Kanawha and Putnam Counties]
• Huntington-Ashland, WV-KY-OH [Cabell and Wayne Counties, and the Graham Tax District in Mason County]
• Martinsburg, WV-Hagerstown, MD [Berkeley County]
• Parkersburg-Marietta, WV-OH [Wood County and the Grant Tax District in Pleasants County]
• Steubenville-Weirton, OH-WV [Brooke and Hancock Counties]
• Wheeling, WV-OH [Marshall and Ohio Counties]

It should be noted that all the areas designated as nonattainment were not in compliance with the annual standard of 15.0 micrograms per cubic meter (µg/m3), based on a 3-year average of annual mean PM2.5 concentrations. However, all areas of West Virginia were found to be attainment with the co-existing 1997 24-hour standard of 65 µg/m3. The design values for the West Virginia nonattainment area monitors for both the annual and 24-hour standards are presented in the PM2.5 table.  

In 2009 EPA determined that the Martinsburg, Parkersburg and Wheeling areas were in attainment with the 1997 standard, based on data for the 3-year period 2006-2008 [74 FR 60199].  

As required by the Clean Air Act, the DAQ submitted demonstrations to EPA for incorporation into the State Implementation Plan (SIP) demonstrating that the Parkersburg, Charleston, Huntington and Weirton areas would attainment the 1997 standard by April of 2010. As shown in the table, data for the 3-year period 2007-2009 shows that these areas did attain the standard.  

2006 PM2.5 Maintenance Areas

In 2006, EPA revised the primary 24-hour standard for PM2.5 to 35 µg/m3, based on a 3-year average of the 98th percentile of 24-hour concentrations. EPA designated 2 areas (4 counties) in West Virginia nonattainment with respect to the 2006 24-hour standard based on data for the 3-year period 2006-2008 [74 FR 58688].  

• Charleston (Kanawha and Putnam Counties)
• Weirton (Brooke and Hancock Counties)

For the subsequent 3-year period, 2007-2009, the Charleston are monitored attainment with the 2006 24-hour standard as shown in the PM2.5 table.  

 

Resources

• PM2.5 Table 1

2015 PM2.5 Maintenance Area Map

 

Sulfur dioxide (SO2) is one of a group of highly reactive gasses known as “oxides of sulfur.” The largest sources of SO2 emissions are from fossil fuel combustion at power plants (66%) and other industrial facilities (29%). Smaller sources of SO2 emissions include industrial processes such as extracting metal from ore, and the burning of high sulfur containing fuels by locomotives, large ships, and non-road equipment. SO2 is linked with a number of adverse effects on the respiratory system.  

EPA first set standards for SO2 in 1971. EPA set a 24-hour primary standard at 0.14 ppm and an annual average standard at 0.03 ppm (to protect health). EPA also set a 3-hour average secondary standard at 0.5 ppm (to protect the public welfare).  

The last review of the SO2 NAAQS was completed in 1996 and the Agency chose not to revise the standards. In the last review, EPA also considered, but did not set, a five minute NAAQS to protect asthmatics at elevated ventilation rates from bronchoconstriction and respiratory symptoms associated with 5-10 minute peaks of SO2.  

All areas of West Virginia are in attainment with the 1971 SO2 NAAQS.  

 

EPA is currently reviewing the SO2 NAAQS. For more information see the EPA website  

• EPA: Sulfur Dioxide (SO2) Pollution

Sulfur Dioxide Maintenance Areas

1-Hour SO₂ Maintenance Areas 

• Cross Creek Tax District of Brooke County
• Clay, Franklin and Washington Tax Districts of Marshall County