This polygon shapefile shows area designations in California as required under Health and Safety Code section 39608 for ozone, nitrogen dioxide, sulfur dioxide, lead, and visibility reducing particles. Visibility-reducing particles consist of suspended particulate matter, which is a complex mixture of tiny particles that consists of dry solid fragments, solid cores with liquid coatings, and small droplets of liquid. These particles vary greatly in shape, size and chemical composition, and can be made up of many different materials such as metals, soot, soil, dust, and salt. 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 three possible designation categories for lead (attainment, nonattainment, and unclassified), and there are four possible designation categories for ozone, nitrogen dioxide, sulfur dioxide, and visibility reducing particles (attainment, nonattainment, nonattainment-transitional, and unclassified). In addition, ozone 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 visibility reducing particle area designations from the prior three-year period (2008-2011) in accordance with the California State Ambient Air Quality Standard.
