Washington Cities Ranked by Indoor Radon Levels

Measured averages from Airthings devices across Washington, USA. Action level: 4 pCi/L — the threshold at which remediation is recommended.

Trentwood has the highest measured indoor radon in Washington at 11.3 pCi/L, based on Airthings measurements across 158 cities.

Updated August 30, 2026

Highest city

11.3pCi/L

Trentwood

Washington city average

1.5pCi/L

across 158 cities

Above action level

13/ 158

cities

Washington Cities Ranked by Indoor Radon Levels
#	Location	Avg level	vs action level
1	Trentwood	11.3 pCi/L	2.8× over
2	Granite Falls	11.0 pCi/L	2.7× over
3	Veradale	9.3 pCi/L	2.3× over
4	Otis Orchards-East Farms	8.2 pCi/L	2.0× over
5	Chewelah	8.1 pCi/L	2.0× over
6	Millwood	7.6 pCi/L	1.9× over
7	Airway Heights	7.4 pCi/L	1.8× over
8	Cheney	5.2 pCi/L	1.3× over
9	Spokane Valley	5.0 pCi/L	1.2× over
10	Davenport	4.7 pCi/L	1.2× over
11	Spokane	4.6 pCi/L	1.2× over
12	Oroville	4.4 pCi/L	1.1× over
13	Brewster	4.2 pCi/L	1.1× over
✓ Below EPA action level (4 pCi/L)
14	Town and Country	3.9 pCi/L	1.0× under
15	Dishman	3.8 pCi/L	0.9× under
16	Liberty Lake	3.6 pCi/L	0.9× under
17	Deer Park	3.3 pCi/L	0.8× under
18	Lakewood	3.3 pCi/L	0.8× under
19	Mill Plain	3.2 pCi/L	0.8× under
20	Cle Elum	3.1 pCi/L	0.8× under
21	Mead	3.1 pCi/L	0.8× under
22	Opportunity	3.1 pCi/L	0.8× under
23	Walnut Grove	3.1 pCi/L	0.8× under
24	Riverbend	2.9 pCi/L	0.7× under
25	Fern Prairie	2.8 pCi/L	0.7× under
26	Ephrata	2.8 pCi/L	0.7× under
27	Graham	2.5 pCi/L	0.6× under
28	Pullman	2.5 pCi/L	0.6× under
29	Washougal	2.3 pCi/L	0.6× under
30	Fairwood	2.2 pCi/L	0.6× under
31	Vancouver	2.2 pCi/L	0.5× under
32	Richland	2.2 pCi/L	0.5× under
33	Newport	2.1 pCi/L	0.5× under
34	Ellensburg	1.9 pCi/L	0.5× under
35	Ridgefield	1.8 pCi/L	0.4× under
36	White Salmon	1.7 pCi/L	0.4× under
37	Orchards	1.7 pCi/L	0.4× under
38	Lake Shore	1.7 pCi/L	0.4× under
39	Brush Prairie	1.6 pCi/L	0.4× under
40	Three Lakes	1.6 pCi/L	0.4× under
41	Tanner	1.6 pCi/L	0.4× under
42	Felida	1.5 pCi/L	0.4× under
43	Leavenworth	1.5 pCi/L	0.4× under
44	Peaceful Valley	1.5 pCi/L	0.4× under
45	Sudden Valley	1.4 pCi/L	0.4× under
46	Rochester	1.4 pCi/L	0.4× under
47	La Center	1.3 pCi/L	0.3× under
48	Minnehaha	1.3 pCi/L	0.3× under
49	Covington	1.2 pCi/L	0.3× under
50	Bremerton	1.2 pCi/L	0.3× under
51	Eastgate	1.2 pCi/L	0.3× under
52	Alderton	1.2 pCi/L	0.3× under
53	West Richland	1.2 pCi/L	0.3× under
54	Frederickson	1.2 pCi/L	0.3× under
55	Meadow Glade	1.1 pCi/L	0.3× under
56	Mirrormont	1.1 pCi/L	0.3× under
57	Battle Ground	1.1 pCi/L	0.3× under
58	Union Hill-Novelty Hill	1.1 pCi/L	0.3× under
59	Mount Vista	1.0 pCi/L	0.3× under
60	Maple Valley	1.0 pCi/L	0.3× under
61	Fall City	1.0 pCi/L	0.2× under
62	Olympia	1.0 pCi/L	0.2× under
63	Medina	0.9 pCi/L	0.2× under
64	East Wenatchee Bench	0.9 pCi/L	0.2× under
65	Bonney Lake	0.9 pCi/L	0.2× under
66	Bellingham	0.9 pCi/L	0.2× under
67	Geneva	0.9 pCi/L	0.2× under
68	Maple Heights-Lake Desire	0.9 pCi/L	0.2× under
69	Camas	0.8 pCi/L	0.2× under
70	Boulevard Park	0.8 pCi/L	0.2× under
71	Kennewick	0.8 pCi/L	0.2× under
72	Blaine	0.8 pCi/L	0.2× under
73	Elk Plain	0.8 pCi/L	0.2× under
74	West Lake Sammamish	0.8 pCi/L	0.2× under
75	Salmon Creek	0.7 pCi/L	0.2× under
76	Burien	0.7 pCi/L	0.2× under
77	Issaquah	0.7 pCi/L	0.2× under
78	Point Roberts	0.7 pCi/L	0.2× under
79	Bryn Mawr-Skyway	0.7 pCi/L	0.2× under
80	Cottage Lake	0.6 pCi/L	0.2× under
81	East Renton Highlands	0.6 pCi/L	0.2× under
82	Enetai	0.6 pCi/L	0.2× under
83	Kingsgate	0.6 pCi/L	0.2× under
84	Mercer Island	0.6 pCi/L	0.2× under
85	Seattle	0.6 pCi/L	0.2× under
86	Bellevue	0.6 pCi/L	0.2× under
87	Gig Harbor	0.6 pCi/L	0.2× under
88	Tacoma	0.6 pCi/L	0.2× under
89	Tanglewilde-Thompson Place	0.6 pCi/L	0.2× under
90	Lake Morton-Berrydale	0.6 pCi/L	0.2× under
91	Shoreline	0.6 pCi/L	0.2× under
92	White Center	0.6 pCi/L	0.2× under
93	West Lake Stevens	0.6 pCi/L	0.1× under
94	Duvall	0.6 pCi/L	0.1× under
95	Kenmore	0.6 pCi/L	0.1× under
96	Bothell	0.6 pCi/L	0.1× under
97	Lynden	0.6 pCi/L	0.1× under
98	Normandy Park	0.5 pCi/L	0.1× under
99	Carnation	0.5 pCi/L	0.1× under
100	Monroe	0.5 pCi/L	0.1× under
101	Kirkland	0.5 pCi/L	0.1× under
102	Five Corners	0.5 pCi/L	0.1× under
103	Renton	0.5 pCi/L	0.1× under
104	South Wenatchee	0.5 pCi/L	0.1× under
105	Yelm	0.5 pCi/L	0.1× under
106	Sequim	0.5 pCi/L	0.1× under
107	Chehalis	0.5 pCi/L	0.1× under
108	Clyde Hill	0.5 pCi/L	0.1× under
109	Langley	0.5 pCi/L	0.1× under
110	Newcastle	0.5 pCi/L	0.1× under
111	Cathcart	0.5 pCi/L	0.1× under
112	Federal Way	0.5 pCi/L	0.1× under
113	Bainbridge Island	0.5 pCi/L	0.1× under
114	Des Moines	0.5 pCi/L	0.1× under
115	Redmond	0.5 pCi/L	0.1× under
116	Ames Lake	0.4 pCi/L	0.1× under
117	Lake Forest Park	0.4 pCi/L	0.1× under
118	Puyallup	0.4 pCi/L	0.1× under
119	Inglewood-Finn Hill	0.4 pCi/L	0.1× under
120	Sammamish	0.4 pCi/L	0.1× under
121	Fircrest	0.4 pCi/L	0.1× under
122	Maltby	0.4 pCi/L	0.1× under
123	City of Sammamish	0.4 pCi/L	0.1× under
124	Yarrow Point	0.4 pCi/L	0.1× under
125	Lake Marcel-Stillwater	0.4 pCi/L	0.1× under
126	Mukilteo	0.4 pCi/L	0.1× under
127	Vashon	0.4 pCi/L	0.1× under
128	East Hill-Meridian	0.4 pCi/L	0.1× under
129	Everett	0.4 pCi/L	0.1× under
130	Meadowdale	0.4 pCi/L	0.1× under
131	Tumwater	0.4 pCi/L	0.1× under
132	Kingston	0.4 pCi/L	0.1× under
133	Rosedale	0.4 pCi/L	0.1× under
134	Suquamish	0.4 pCi/L	0.1× under
135	University Place	0.4 pCi/L	0.1× under
136	Woodinville	0.4 pCi/L	0.1× under
137	Martha Lake	0.4 pCi/L	0.1× under
138	Mountlake Terrace	0.4 pCi/L	0.1× under
139	Brier	0.3 pCi/L	0.1× under
140	Lynnwood	0.3 pCi/L	0.1× under
141	Mill Creek	0.3 pCi/L	0.1× under
142	Silver Firs	0.3 pCi/L	0.1× under
143	Alderwood Manor	0.3 pCi/L	0.1× under
144	North Bend	0.3 pCi/L	0.1× under
145	Lacey	0.3 pCi/L	0.1× under
146	Snohomish	0.3 pCi/L	0.1× under
147	Lofall	0.3 pCi/L	0.1× under
148	Camano	0.3 pCi/L	0.1× under
149	North Creek	0.3 pCi/L	0.1× under
150	Arlington	0.3 pCi/L	0.1× under
151	Fife Heights	0.3 pCi/L	0.1× under
152	Marysville	0.3 pCi/L	0.1× under
153	Burlington	0.3 pCi/L	0.1× under
154	Orting	0.3 pCi/L	0.1× under
155	Port Orchard	0.2 pCi/L	0.1× under
156	Stanwood	0.2 pCi/L	0.0× under
157	Anacortes	0.2 pCi/L	0.0× under
158	Kent	0.2 pCi/L	0.0× under

See USA cities ranked by radon level See all States ranked by radon level