- 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.
There were also a few runner-ups, whose air wasn't scot-free of ozone pollution year-round, but were pretty damn good in the scheme of things in that they boasted "no days in the unhealthy level for short-term particle pollution and were on the list of the cleanest cities for year-round particle pollution." In alphabetical order, they are: