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    • Clean Air Status and Trends Network (CASTNET): Visibility

    Metadata Updated: February 10, 2026

    Nephelometer data (conforms to IMPROVE network standards) from October 1993 to June 2002. This table is no longer updated.

    Access & Use Information

    Public: This dataset is intended for public access and use. License: See this page for license information.

    Downloads & Resources

    References

    https://edg.epa.gov/metadata/rest/document?id=%7B78745BEC-83F3-434E-849D-4D7BA4D4790C%7D
    https://edg.epa.gov/metadata/catalog/search/resource/details.page?uuid=%7B78745BEC-83F3-434E-849D-4D7BA4D4790C%7D

    Dates

    Metadata Created Date January 30, 2026
    Metadata Updated Date February 10, 2026
    Data Update Frequency irregular

    Metadata Source

    Harvested from EPA Non Geo Repository

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date January 30, 2026
    Metadata Updated Date February 10, 2026
    Publisher U.S. EPA Office of Air and Radiation (OAR) - Office of Atmospheric Programs (OAP)
    Maintainer
    Identifier 78745BEC-83F3-434E-849D-4D7BA4D4790C
    Data First Published 2014-01-01
    Data Last Modified 2014-01-01
    Public Access Level public
    Data Update Frequency irregular
    Bureau Code 020:00
    Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
    Metadata Catalog ID https://edg.epa.gov/data/nongeo_data.json
    Schema Version https://project-open-data.cio.gov/v1.1/schema
    Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
    Harvest Object Id 8fb7e67b-32c3-4182-9c01-01f33313084e
    Harvest Source Id 9c1c2b5b-7925-4ca2-a663-ca2131653db1
    Harvest Source Title EPA Non Geo Repository
    License https://edg.epa.gov/EPA_Data_License.htm
    Old Spatial -180.0,18.0,-66.0,72.0
    Program Code 020:072
    Related Documents https://edg.epa.gov/metadata/rest/document?id=%7B78745BEC-83F3-434E-849D-4D7BA4D4790C%7D, https://edg.epa.gov/metadata/catalog/search/resource/details.page?uuid=%7B78745BEC-83F3-434E-849D-4D7BA4D4790C%7D
    Source Datajson Identifier True
    Source Hash 9584a6e6ffc9dfa2fb3920bc6e5057624c6426607089f4d822165335ca886678
    Source Schema Version 1.1
    Spatial {"type": "Polygon", "coordinates": -180.0, 18.0, -180.0, 72.0, -66.0, 72.0, -66.0, 18.0, -180.0, 18.0}

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