CALIFORNIA - EPA Map of Radon Zones
The purpose of this map is to assist National, State and local organizations to target their resources and to
implement radon-resistant building codes.
This map is not intended to determine if a home in a given zone should be tested for radon.
Homes with elevated levels of radon have been found in all three zones.
All homes should be tested, regardless of zone designation.
http://www.epa.gov/radon/zonemap.html
~ EL
NORTE
MENOOCIH
IMPORTANT: Consult the publication entitled "Preliminary Geologic Radon Potential
Assessment of California" (USGS Open-file Report 93-292-1) before using this map.
See http://energy.cr.usgs.gov/radon/grpinfo.html This document contains
information on radon potential variations within counties. EPA also recommends that
this map be supplemented with any available local data in order to further
understand and predict the radon potential of a specific area.
SAN FRANCISCO
Zone 1
Zone 2
Zone 3
SISKIYOU
MODOC
TRIN
ITY { SHASTA
LASSEN
TEHAMA
PLUMAS
GLENN
BUTTE
COLU
SONOMA
NAPA YOLO
DORADO
LANO
ALPINE
CONTRA COSTA
CALA-
JOAQUI
SAN MATEO
SANTA \ STANISLAUS
CLARA
POSA
SANTA CRUZ
MADERA
SAN BENITO
FRESNO
MONTEREY
TULARE
KINGS
INYO
KERN
SANTA
BARBARA
SAN
BERNARDINO
VENTURA
LOS
ANGELES
ORANGE
R VERS DE
SAN LUIS
OBISPO
SAN

DIEGO
IMPERIAL |

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