
Treasure Valley air quality has improved so much that the Boise metro area (including Nampa) has been listed among the Top 25 cleanest cities for annual particle pollution in the United Sates.
The American Lung Association's State of the Air 2012 moved Ada County smog levels from an "F" ranking in its last report up to a "C" grade. Ozone (smog) is the most widespread air pollutant, created by the reaction of sunlight on emissions from vehicles and other sources. Ozone is blamed for wheezing, coughing, asthma attacks and premature death.
On the downside, Benewah, Lemhi and Shoshone counties all received an "F" in the latest report for short-term particle pollution.
The air is a bit clearer in Butte and Kootenai counties—two of the cleanest, when it comes to ozone.
But the Lung Association still warned that more than 40 percent of people in the United States—more than 127 million people—live in areas where air pollution continues to threaten their health.
On August 17 Boise joined a number of key cities that are embracing idling reduction programs. In districts across downtown, the city has posted metal signs that say “Turn your key / be idle free boise.org,” urging residents to switch off their vehicles when parked. The sign sports a logo and a QR code that links to the website.
“Our goal is to educate residents on the effects of idling,” said spokesman for the mayor Adam Park.
The Environmental Protection Agency and the Department of Transportation unveiled new fuel economy window stickers Wednesday. You will see them on all new vehicles beginning with the 2013 model year. Simply put, the sticker will, for the first time, estimate annual fuel costs and the vehicle's overall environmental impact.

Following an oppressively hot weekend, the Treasure Valley begins another week with a yellow air alert.
The Department of Environmental Quality has posted the warning, with special attention for sensitive people—very young children, seniors—to take extra caution. The DEQ has already posted yet another yellow alert for Tuesday. Track the Air Quality Index atairnow.gov.