WASHINGTON - 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
SAN JUAN
4)
WHATCOM
ISLAND
SKAGT
CLALLAM
OKANOGAN
JEFFERSON
SNOHOM SH
FERRY
PEND
OREILLE
KIT-
STEVENS
CHELAN
SAP
MASON
GRAYS
HARBOR
KING
DOUGLAS
PIERCE
THURSTON
PIERCE
PAC F C
LINCOLN
KTTTAS
SPOKANE
GRANT
LEWS
ADAMS
COWLTZ
YAKIMA
WH TMAN
SKAMANA
FRANKLIN
CLARK
BENTON
GARFIELD
KL CK TAT
WALLA WALLA
COLUMBI
ASOTIN
WAHKIAKUM
Zone 1
Zone 2
Zone 3
IMPORTANT: Consult the publication entitled "Preliminary Geologic Radon Potential
Assessment of Washington" (USGS Open-file Report 93-292-J) before using this map.
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.

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