As efforts to improve air quality continue around the Commonwealth, the focus in Northern Virginia is to reduce emissions from motor vehicles. Vehicle emissions also contain pollutants that may affect water quality in the Chesapeake Bay and its tributaries.
Vehicles are the single greatest source of pollutants in Northern Virginia.
Most of the nearly 1.4 million vehicles in Northern Virginia have emissions control equipment. Newer vehicles typically run much more cleanly than the vehicles they replace. But the total amount of vehicle emissions continues to increase with the number of vehicle miles traveled. To ensure that vehicles operate as cleanly as possible, an emissions inspection program has been an important part of Northern Virginia's air quality plan since 1982. In compliance with this federal mandate, DEQ has designed the program for maximum convenience, efficiency and reliability.