Burning fossil fuels for transportation and to generate energy creates air pollutants. Air pollution is a recognized concern in East Tennessee, just as in other parts of the country. The Environmental Protection Agency (EPA) announced in April 2004 that Knox County and several surrounding counties do not meet the National Ambient Air Quality Standard for ground-level ozone, also known as smog. Increased ozone levels can lead to difficulty breathing, irritation of the eyes, nose, and throat, and chest tightness, among other symptoms. By focusing on energy efficiency, trip reductions, and alternative fuels, KUB works to reduce pollutant emissions and educate its employees and the community about ways to improve air quality.