The non-profit's annual State Of The Air report for 2017 lists six American cities that didn't log a single "bad air" day during the 2013-2015 window studied. That means they didn't clock a single day with high ozone or particle pollution, and were among the 25 cities with the lowest year-round particle levels. These are the metro areas -- listed in alphabetical order -- where the air astonishingly never broached unhealthy territory, even during summer months, when air pollution tends to kick into high gear:
- Burlington-South Burlington, VT
- Cape Coral-Fort Myers-Naples, FL
- Elmira-Corning, NY
- Honolulu, HI
- Palm Bay-Melbourne-Titusville, FL
- Wilmington, NC
Encouragingly, this year's list boasts two more metro areas than last year's, and includes Wilmington for the first time ever. Both Palm Bay-Melbourne-Titusville and Cape Coral-Fort Myers-Naples have made the list previously, though Salinas, CA unfortunately fell off, after making into the 2016 roundup.