EPA’s Office of Research and Development has requested CASAC peer review its third external review draft "Integrated Science Assessment for Ozone and Related Photochemical Oxidants," intended to provide a synthesis and evaluation of science relevant for revising the national ambient air quality standards for particulate matter. The CASAC previously reviewed the first external review draft of the Agency's Integrated Science Assessment and previously reviewed the second external review draft of the Agency's Integrated Science Assessment.
Under the Clean Air Act, EPA is required to carry out a periodic review and revision, as appropriate, of the air quality criteria and the primary and secondary standards for six criteria air pollutants, which include ozone. Primary standards set limits to protect public health, including the health of "sensitive" populations such as asthmatics, children, and the elderly. Secondary standards set limits to protect public welfare, including protection against decreased visibility, damage to animals, crops, vegetation, and buildings.