Few things are as important as the quality of the air we breathe. Although a few Virginia regions have room for improvement, overall air quality in the Commonwealth has risen significantly in recent years.
Why is This Important?
Poor air quality causes increased deaths, especially among the very young and the very old. It reduces water quality, contributes to climate change, and damages forest resources, agriculture, buildings, and infrastructure. It also makes Virginia a less attractive place to live, do business in, or visit — factors that have consequences for both the economy and the quality of life.
How is Virginia Doing?
Ground level ozone (the main ingredient in smog) is a colorless gas formed by the reaction of sunlight with vehicle emissions, gasoline fumes, solvent vapors, and power plant and industrial emissions. Particle pollution is a complex mixture of both solid and liquid particles of varying sizes; the most dangerous kind are the tiny particulates found in soot, dust, smoke and fumes caused by burning coal, oil, diesel, and other fuels.
Virginia’s air quality has markedly improved in recent years. For example, residents' average exposure to fine particulates -- particles of dust, soot, aerosols, and dust fine enough to be inhaled -- has decreased every year over the past decade and more. Average exposure in Virginia for 2015 was 8.3 micrograms of fine particles per cubic meter -- lower than the United States average (9.5) and ranking 20th in the nation. Among peer states, Maryland (9.6), Tennessee (9.1), and North Carolina (8.7) all had higher average exposure levels in 2015. Wyoming (5.0) had the lowest in the US.
Based in part on over 1,000 post-2008 studies showing that ozone levels greatly affect public health (especially for at-risk groups like the young, the elderly, and those with COPD and asthma), in October 2015 the EPA updated the acceptable limits for ground-level smog: down to 70 micrograms of fine particulates per billion from the 75 ppb levels set in 2008.
Virginia has also significantly reduced the number of days when the federal ozone standard have been exceeded -- dropping from 341 days per 3-year average in 2004-06 to just 13 days across 2013-15. Among Virginia's regions, the highly congested Northern region continues to have the poorest air quality, with an average of 9.3 days exceeding the ozone standard over that same 2013-15 period.
What Influences Air Quality?
Heavy automobile use is one chief contributor to air pollution in the US; coal-burning plants are another. Increased efficiency of automobile engines, growth in the use of hybrid vehicles, and more use of alternative modes of travel can all contribute to better air quality. Similarly, wider use of clean energy sources for generating electricity and other needs can also have major impact. All have the attendant benefit of helping to reduce greenhouse gases, which contribute so heavily to climate change.
Certain emissions (from cars, coal plants, etc.) are subject to reductions or caps mandated by state, federal, and international laws and obligations. Regulations on emission rates need to be tightened periodically to maintain air quality when economic activity increases or when it becomes clear that older standards are no longer adequate.
For example, since 2008, US standards for regulating vehicle fuel efficiency and emissions (which had generally remained static since the 1970s) rose significantly, leading both domestic and foreign automakers to develop cleaner engines and hybrid alternatives for many models in their fleets of cars and trucks. As a result, vehicle fuel economy rose an average of 3 mpg from 2008 to 2014, while average CO2 emissions decreased 58 grams per mile over the same period. At the same time, total sales of hybrid vehicles rose from 315,688 in 2008 to 507,272 in 2014, an increase of 62 percent, with US automakers also upping their share of the overall hybrid market by nearly 42 percent.
Finally, global atmospheric circulation can cause emissions from other states and even other countries to affect Virginia.
What is the State's Role?
Air quality standards are established by the federal government via the Clean Air Act and are the main factor behind the steady improvements in air quality the US has seen since the law was first passed in 1970. The Virginia Department of Environmental Quality is charged with enforcing these federal standards in the Commonwealth.
What Can Citizens Do?
Individuals and groups are strongly encouraged to be active participants in resource management. Reducing smog and particulate emissions through increased use of hybrid vehicles is just one place to start. To learn more about Virginia's environment, stewardship and public participation opportunities, and the partners engaged in conservation, please visit the Dept. of Conservation and Recreation's Environmental Education pages or the Virginia Conservation Network.
State rankings are ordered so that #1 is understood to be the best.
Data Definitions and Sources
Virginia Department of Environmental Quality, www.deq.virginia.gov/Programs/Air.aspx
Data collected from the EPA
is used to estimate particulate exposure: www.epa.gov/airdata
Population-weighted average exposure to fine particulates (2.5 micron and smaller) measured in micrograms of fine particulate per cubic meter.
Center for Climate and Energy Solutions, Federal Vehicle Standards, www.c2es.org/federal/executive/vehicle-standards
Environmental Protection Agency, Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends: 1975-2015
US Dept. of Transportation, Bureau of Transportation Statistics, Table 1-19: Sales of Hybrid Vehicles in the United States
United Health Foundation, America's Health Rankings
See the Data Sources and Updates Calendar for a detailed list of the data resources used for indicator measures on Virginia Performs.