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CGS Mineral Hazards: Indoor Radon Potential Zones

This digital layer contains polygons (vector format) of portions of California designated as having high, moderate, low, or unknown potential for homes to exceed the U.S. EPA recommended radon action level of 4.0 picocuries per liter in indoor air. Only a portion of California is covered by the studies included in this dataset.

Data files

Data title and descriptionAccess dataFile detailsLast updated

CSV

Download
CSV
12/24/25

Shapefile

DownloadZIP
12/24/25

GeoJSON

DownloadGEOJSON
12/24/25

KML

DownloadKML
12/24/25

Supporting files

Data title and descriptionAccess dataFile detailsLast updated

ArcGIS Hub Dataset

HTML
12/24/25

ArcGIS GeoService

ARCGIS GEOSERVICES REST API
12/24/25

API endpoint

Dataset Name

Use the query web API to retrieve data with a set of basic parameters. Copy the API endpoint you need to start.

Usage documentation