This polygon shapefile contains area designations of carbon monoxide (CO) levels in California as required under Health and Safety Code section 39608. The designations are consistent with the criteria established in the California Code of Regulations, title 17, sections 70300 through 70306, and Appendices 1 through 3, thereof. There are four possible designation categories: attainment, nonattainment, nonattainment-transitional, and unclassified. Nonattainment areas are geographic areas which have not met National Ambient Air Quality Standards for Carbon Monoxide air pollution. In addition, CO nonattainment areas have been assigned a classification, commensurate with the severity of their air quality problem, under Health and Safety Code section 40921.5. The State area designations are reviewed annually and approved by the State Air Resources Board. Projection: Teale Albers, NAD83This shapefile can be used to identify state carbon monoxide pollution area designations from the prior three-year period (2008-2011) in accordance with the California State Ambient Air Quality Standard.