aspen trees and clear sky

Air Quality

Boulder County works to improve indoor and outdoor air quality through education, monitoring and policy.
Clean Air Challenge logo

Clean Air Challenge

Leave your car at home one or more days a week during the high ozone months of July and August and you could win great prizes while helping to reduce greenhouse gas emissions.

ditch burning on a farm

Burn Permits

Burn permits are required for open burning of slash in Boulder County. Permits may be denied if a practical alternative method of disposal exists. Learn more about requirements for spring, summer, fall, and winter, as well as alternatives to open burning.



Mold (or mildew) is the common name for fungi in the indoor environment, although molds are found everywhere in both the indoor and outdoor environment. Learn more about the health effects, prevention, and how to fix the problem.