The purpose of this Visibilty Monitoring Guidance Document is to provide a written reference for organizations conducting monitoring of visibility and particulate matter for regulatory, planning, or research purposes. Possible users include the government sector (Federal, State, regional, local, and Tribal air quality agencies), industry, consulting firms, academia, or nonprofit organizations. The information in this document includes: background on the visibility protection requirements of the Clean Air Act and related regulations; a summary of visibility monitoring goals and objectives set forth in the Clean Air Act and related EPA regulations; considerations and recommendations for developing effective visibility monitoring sites, and networks, particularly for implementation of the monitoring requirements for the PM-2.5 and regional haze regulatory programs. These considerations and recommendations address visibility definitions and theory, monitoring goals and objectives, data quality objectives, monitoring methods, data archive and data applications, and network design; and descriptions of current visibility measurement methods and monitoring protocols, particularly those used under the Interagency Monitoring of Protected Visual Environments (IMPROVE) program.

Performing organization: Science Applications International Corp. Shipping list no.: 99-0855-M. "June 1999." Includes bibliographical references (pages 25-27). "EPA-454/R-99-003." "Contrato no. de U.S.E.P.A.: 68D30030, tarea de trabajo II-89." Microfiche.