June 22, 2007
EPA proposes stronger standards for smog
2007 Volvo S80 V8 AWD. Click image to enlarge
Washington, D.C. – The U.S. Environmental Protection Agency (EPA) is proposing to strengthen the country’s air quality standards for ground-level ozone, revising the standards for the first time since 1997. The proposal is based on the most recent scientific evidence about the health effects of ozone, which is the primary component of smog.
The proposal recommends an ozone standard within a range of 0.070 to 0.075 parts per million (ppm). The EPA is also taking comments on alternative standards, within a range from 0.060 ppm up to 0.08 ppm, which is the current eight-hour ozone standard.
Ozone can harm lungs; the EPA is particularly concerned about individuals with asthma or other lung diseases, as well as those who spend a lot of time outside. Ground-level ozone is not emitted directly into the air, but is created through a reaction of nitrogen oxides and volatile organic compound emissions in the presence of sunlight. Major man-made sources of ozone precursors are motor vehicle exhaust, emissions from industrial and electric utilities, gasoline vapours and chemical solvents.