The Clean Air Act identifies two types of national ambient air quality standards. Primary standards provide public health protection, including protecting the health of sensitive populations such as people with asthma, children, and the elderly. Secondary standards provide public welfare protection, including protection against decreased visibility and damage to animals, crops, vegetation, and buildings.
There are two air quality monitoring stations in Thurston County monitoring ozone and fine particulate matter (PM 2.5). The region’s air quality has continued to meet air quality standards over the last 15 years.