There are over 70-thousand people in Wyoming affected with asthma, COPD, or lung cancer. Thankfully, the air is one of the cleanest in the U.S. That news comes from the National Lung Association comprehensive report State of the Air 2017.

There were three main areas in the study such as cities or counties of risk, particle pollutants, and ozone pollutants. Particle pollution is toxins in the air. It could be from a factory, forest fire, or car exhaust. Ozone pollution is ozone gas often described as smog.

Wyoming was not listed in any category for areas of risk. It was not on any of the worst polluted cities or counties. The only time the National Lung Association brought up the Cowboy State was for the clean 307 air.

Two Wyoming cities were ranked as the Top 25 Cleanest U.S. Cites for Year-Round Particle Pollution. Cheyenne tied for first place. Casper came in third place in the same category. Nearly every clean list from the State of the Air 2017 showcased Wyoming with good quality air.

The report also included a letter grade for the quality of air for most of the counties in Wyoming. The following are the grades for the state:

Albany = B
Big Horn = A
Campbell = A
Carbon = B
Converse = B
Fremont = A
Laramie = C
Natrona = B
Sublette = B
Sweetwater = C
Teton = A
Uinta = B
Weston = A