Over 200 is the purple (very unhealthy ... that’s allowing it to get into these valleys.” Colin said the air quality index ...

If the air quality in your area is compromised, there are several things you can do to protect yourself. Special attention should be paid to those who have compromised respiratory, lung or heart ...

Hanoi hit the purple “very unhealthy” level on the IQAir Index for nine out of the last 17 days, which denotes an air quality level of 201 or higher, just below the most dangerous “hazardous.” ...

Oregon DEQ issues air quality advisory for several counties due to air stagnation trapping smoke and pollutants.