Introduction
Radon is a natural, odorless, colorless, tasteless, radioactive gas. Radon is most commonly found in uranium coated materials in the ground, therefore accumulating in subterranean areas such as basements and is emitted from the decay of uranium. It can also occur in some groundwater and hot springs. Climate change may cause previously trapped Radon underground to be released as permafrost thaws, especially in areas like Alaska, Canada, the Arctic, Greenland, and Russia.
Epidemiological studies have found that Radon can cause cancer (it is the second-most cause of lung cancer, after smoking). Radon poisoning can lay dormant, showing no symptoms, for years. The United States Environmental Protection Agency (EPA) estimates one third of homes have radon levels greater than the recommended level (4.0 picocurie per liter).
See for yourself how radon levels change by state by surveying the data in the charts.
| # | State | Radon Level | Average Daily UV Irradiance |
|---|---|---|---|
| 1 | Alaska | 10.7 pCi/L | |
| 2 | South Dakota | 9.6 pCi/L | 2,268 J/m² |
| 3 | Pennsylvania | 8.6 pCi/L | 2,249 J/m² |
| 4 | Ohio | 7.8 pCi/L | 2,351 J/m² |
| 5 | Washington | 7.5 pCi/L | 2,088 J/m² |
| 6 | Kentucky | 7.4 pCi/L | 2,711 J/m² |
| 7 | Montana | 7.4 pCi/L | 2,174 J/m² |
| 8 | Idaho | 7.3 pCi/L | 2,551 J/m² |
| 9 | Colorado | 6.8 pCi/L | 3,535 J/m² |
| 10 | Iowa | 6.1 pCi/L | 2,375 J/m² |
| 11 | West Virginia | 6.1 pCi/L | 2,527 J/m² |
| 12 | North Dakota | 6 pCi/L | 1,987 J/m² |
| 13 | Maine | 5.9 pCi/L | 1,944 J/m² |
| 14 | Wisconsin | 5.7 pCi/L | 2,098 J/m² |
| 15 | New Hampshire | 5.6 pCi/L | 2,107 J/m² |
| 16 | Maryland | 5.4 pCi/L | 2,499 J/m² |
| 17 | Illinois | 5.3 pCi/L | 2,506 J/m² |
| 18 | Nebraska | 5.2 pCi/L | 2,576 J/m² |
| 19 | Wyoming | 5 pCi/L | 2,794 J/m² |
| 20 | Kansas | 4.9 pCi/L | 2,892 J/m² |
| 21 | Tennessee | 4.8 pCi/L | 2,910 J/m² |
| 22 | Indiana | 4.7 pCi/L | 2,427 J/m² |
| 23 | Minnesota | 4.6 pCi/L | 2,076 J/m² |
| 24 | New Jersey | 4.4 pCi/L | 2,372 J/m² |
| 25 | Utah | 4.4 pCi/L | 3,191 J/m² |
| 26 | Missouri | 4.3 pCi/L | 2,658 J/m² |
| 27 | Rhode Island | 4.3 pCi/L | 2,210 J/m² |
| 28 | New York | 4.2 pCi/L | 2,140 J/m² |
| 29 | North Carolina | 4 pCi/L | 2,968 J/m² |
| 30 | Alabama | 3.9 pCi/L | 3,225 J/m² |
| 31 | Massachusetts | 3.9 pCi/L | 2,220 J/m² |
| 32 | New Mexico | 3.9 pCi/L | 3,723 J/m² |
| 33 | Vermont | 3.7 pCi/L | 2,004 J/m² |
| 34 | Virginia | 3.6 pCi/L | 2,710 J/m² |
| 35 | Michigan | 3.5 pCi/L | 2,045 J/m² |
| 36 | Connecticut | 3.4 pCi/L | 2,262 J/m² |
| 37 | Nevada | 3.4 pCi/L | 3,197 J/m² |
| 38 | Oregon | 3.1 pCi/L | 2,399 J/m² |
| 39 | Arkansas | 2.5 pCi/L | 3,031 J/m² |
| 40 | Oklahoma | 2.5 pCi/L | 3,099 J/m² |
| 41 | Delaware | 2.4 pCi/L | 2,505 J/m² |
| 42 | South Carolina | 2.4 pCi/L | 3,179 J/m² |
| 43 | California | 2.3 pCi/L | 3,216 J/m² |
| 44 | Georgia | 2.3 pCi/L | 3,277 J/m² |
| 45 | Texas | 2.1 pCi/L | 3,538 J/m² |
| 46 | Arizona | 1.9 pCi/L | 3,728 J/m² |
| 47 | Florida | 1.8 pCi/L | 3,636 J/m² |
| 48 | Mississippi | 1.2 pCi/L | 3,221 J/m² |
| 49 | Louisiana | 1.1 pCi/L | 3,346 J/m² |
| 50 | Hawaii | 0 pCi/L |
Radon Level by State
Alabama
Radon Level
3.9 pCi/L
Ranked in the US
#30
Average Daily UV Irradiance
3,225 J/m²
Ranked in the US
#8
Alaska
Radon Level
10.7 pCi/L
Ranked in the US
#1
Arizona
Radon Level
1.9 pCi/L
Ranked in the US
#46
Average Daily UV Irradiance
3,728 J/m²
Ranked in the US
#1
Arkansas
Radon Level
2.5 pCi/L
Ranked in the US
#39
Average Daily UV Irradiance
3,031 J/m²
Ranked in the US
#15
California
Radon Level
2.3 pCi/L
Ranked in the US
#43
Average Daily UV Irradiance
3,216 J/m²
Ranked in the US
#10
Colorado
Radon Level
6.8 pCi/L
Ranked in the US
#9
Average Daily UV Irradiance
3,535 J/m²
Ranked in the US
#5
Connecticut
Radon Level
3.4 pCi/L
Ranked in the US
#36
Average Daily UV Irradiance
2,262 J/m²
Ranked in the US
#36
Delaware
Radon Level
2.4 pCi/L
Ranked in the US
#41
Average Daily UV Irradiance
2,505 J/m²
Ranked in the US
#27
Florida
Radon Level
1.8 pCi/L
Ranked in the US
#47
Average Daily UV Irradiance
3,636 J/m²
Ranked in the US
#3
Georgia
Radon Level
2.3 pCi/L
Ranked in the US
#44
Average Daily UV Irradiance
3,277 J/m²
Ranked in the US
#7
Hawaii
Radon Level
0 pCi/L
Ranked in the US
#50
Idaho
Radon Level
7.3 pCi/L
Ranked in the US
#8
Average Daily UV Irradiance
2,551 J/m²
Ranked in the US
#24
Illinois
Radon Level
5.3 pCi/L
Ranked in the US
#17
Average Daily UV Irradiance
2,506 J/m²
Ranked in the US
#26
Indiana
Radon Level
4.7 pCi/L
Ranked in the US
#22
Average Daily UV Irradiance
2,427 J/m²
Ranked in the US
#30
Iowa
Radon Level
6.1 pCi/L
Ranked in the US
#10
Average Daily UV Irradiance
2,375 J/m²
Ranked in the US
#32
Kansas
Radon Level
4.9 pCi/L
Ranked in the US
#20
Average Daily UV Irradiance
2,892 J/m²
Ranked in the US
#18
Kentucky
Radon Level
7.4 pCi/L
Ranked in the US
#6
Average Daily UV Irradiance
2,711 J/m²
Ranked in the US
#20
Louisiana
Radon Level
1.1 pCi/L
Ranked in the US
#49
Average Daily UV Irradiance
3,346 J/m²
Ranked in the US
#6
Maine
Radon Level
5.9 pCi/L
Ranked in the US
#13
Average Daily UV Irradiance
1,944 J/m²
Ranked in the US
#49
Maryland
Radon Level
5.4 pCi/L
Ranked in the US
#16
Average Daily UV Irradiance
2,499 J/m²
Ranked in the US
#28
Massachusetts
Radon Level
3.9 pCi/L
Ranked in the US
#31
Average Daily UV Irradiance
2,220 J/m²
Ranked in the US
#38
Michigan
Radon Level
3.5 pCi/L
Ranked in the US
#35
Average Daily UV Irradiance
2,045 J/m²
Ranked in the US
#46
Minnesota
Radon Level
4.6 pCi/L
Ranked in the US
#23
Average Daily UV Irradiance
2,076 J/m²
Ranked in the US
#45
Mississippi
Radon Level
1.2 pCi/L
Ranked in the US
#48
Average Daily UV Irradiance
3,221 J/m²
Ranked in the US
#9
Missouri
Radon Level
4.3 pCi/L
Ranked in the US
#26
Average Daily UV Irradiance
2,658 J/m²
Ranked in the US
#22
Montana
Radon Level
7.4 pCi/L
Ranked in the US
#7
Average Daily UV Irradiance
2,174 J/m²
Ranked in the US
#40
Nebraska
Radon Level
5.2 pCi/L
Ranked in the US
#18
Average Daily UV Irradiance
2,576 J/m²
Ranked in the US
#23
Nevada
Radon Level
3.4 pCi/L
Ranked in the US
#37
Average Daily UV Irradiance
3,197 J/m²
Ranked in the US
#11
New Hampshire
Radon Level
5.6 pCi/L
Ranked in the US
#15
Average Daily UV Irradiance
2,107 J/m²
Ranked in the US
#42
New Jersey
Radon Level
4.4 pCi/L
Ranked in the US
#24
Average Daily UV Irradiance
2,372 J/m²
Ranked in the US
#33
New Mexico
Radon Level
3.9 pCi/L
Ranked in the US
#32
Average Daily UV Irradiance
3,723 J/m²
Ranked in the US
#2
New York
Radon Level
4.2 pCi/L
Ranked in the US
#28
Average Daily UV Irradiance
2,140 J/m²
Ranked in the US
#41
North Carolina
Radon Level
4 pCi/L
Ranked in the US
#29
Average Daily UV Irradiance
2,968 J/m²
Ranked in the US
#16
North Dakota
Radon Level
6 pCi/L
Ranked in the US
#12
Average Daily UV Irradiance
1,987 J/m²
Ranked in the US
#48
Ohio
Radon Level
7.8 pCi/L
Ranked in the US
#4
Average Daily UV Irradiance
2,351 J/m²
Ranked in the US
#34
Oklahoma
Radon Level
2.5 pCi/L
Ranked in the US
#40
Average Daily UV Irradiance
3,099 J/m²
Ranked in the US
#14
Oregon
Radon Level
3.1 pCi/L
Ranked in the US
#38
Average Daily UV Irradiance
2,399 J/m²
Ranked in the US
#31
Pennsylvania
Radon Level
8.6 pCi/L
Ranked in the US
#3
Average Daily UV Irradiance
2,249 J/m²
Ranked in the US
#37
Rhode Island
Radon Level
4.3 pCi/L
Ranked in the US
#27
Average Daily UV Irradiance
2,210 J/m²
Ranked in the US
#39
South Carolina
Radon Level
2.4 pCi/L
Ranked in the US
#42
Average Daily UV Irradiance
3,179 J/m²
Ranked in the US
#13
South Dakota
Radon Level
9.6 pCi/L
Ranked in the US
#2
Average Daily UV Irradiance
2,268 J/m²
Ranked in the US
#35
Tennessee
Radon Level
4.8 pCi/L
Ranked in the US
#21
Average Daily UV Irradiance
2,910 J/m²
Ranked in the US
#17
Texas
Radon Level
2.1 pCi/L
Ranked in the US
#45
Average Daily UV Irradiance
3,538 J/m²
Ranked in the US
#4
Utah
Radon Level
4.4 pCi/L
Ranked in the US
#25
Average Daily UV Irradiance
3,191 J/m²
Ranked in the US
#12
Vermont
Radon Level
3.7 pCi/L
Ranked in the US
#33
Average Daily UV Irradiance
2,004 J/m²
Ranked in the US
#47
Virginia
Radon Level
3.6 pCi/L
Ranked in the US
#34
Average Daily UV Irradiance
2,710 J/m²
Ranked in the US
#21
Washington
Radon Level
7.5 pCi/L
Ranked in the US
#5
Average Daily UV Irradiance
2,088 J/m²
Ranked in the US
#44
West Virginia
Radon Level
6.1 pCi/L
Ranked in the US
#11
Average Daily UV Irradiance
2,527 J/m²
Ranked in the US
#25
Wisconsin
Radon Level
5.7 pCi/L
Ranked in the US
#14
Average Daily UV Irradiance
2,098 J/m²
Ranked in the US
#43
Wyoming
Radon Level
5 pCi/L
Ranked in the US
#19
Average Daily UV Irradiance
2,794 J/m²
Ranked in the US
#19