Short-term kit
RA100 short-term liquid scintillation radon test kit
- Lab fee extra
Method: Liquid scintillation
In home: 48 to 96 hours
Locations and reports
Radon Levels in Petersburg Borough, Alaska
EPA has no radon zone on file for Petersburg Borough, only 1 radon test from it is on file with CDC (2022), and the only way to know your home's level is to test it.
Data checked By Radon411Methodology
Nearest county
3.1%
Anchorage Municipality, 637 miles
- Anchorage Municipality
- 3.1%
- Alaska
- 11.5%
Share at 4+ pCi/L, 130 tests, 2022
Ground above low
93.5%
14.3 pts above Alaska
- Petersburg Borough
- 93.5%
- Alaska
- 79.2%
Share of land USGS rates moderate or high potential
Tests reported
1
Too few for a share
- Petersburg Borough
- 1
- Needed
- 30
2022
Read a result for Petersburg Borough
Starts at EPA's action level
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 4.0 pCi/L
At or above 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is at or above 4 pCi/L. EPA recommends fixing a home when the radon level is 4 pCi/L or higher.
The data
Petersburg Borough, At a glance
Petersburg Borough at a glance
Predicted: EPA radon zone
No EPA zone on file
Radon411 has no EPA radon zone on file for Petersburg Borough, Alaska, and it does not guess one.
A prediction for the whole county, not a measurement of any address: elevated homes occur in all three zones.
USGS geologic potential: Moderate across 94% of the county's area
Predicted: no EPA zone on file yet
Measured: tests reported to CDC
Radon tests reported for Petersburg Borough, 2022
CDC holds 1 reported test for Petersburg Borough in 2022, a result of 0.2 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Petersburg Borough beside the counties around it is how this page reads it.
What these figures count
Only 1 test was reported to CDC for Petersburg Borough over 2022, and tests are often run on homes being sold or already suspected of a problem: so few describe neither the borough or census area nor this house.
Measured: CDC tracking data. Measured data period: 2022.
Petersburg Borough, Compared
Petersburg Borough radon figures, compared
Calculated by Radon411CDC's largest figure for Petersburg Borough rests on 1 test in 2022, 0 of them at or above 4 pCi/L, so each test moves its share by 100.0 points and no rank or comparison is drawn from it. Results reached as high as 0.2 pCi/L, with a middle value of 0.2 pCi/L.
The nearest counties with a figure are Anchorage Municipality (637 miles away) at 3.1%, Matanuska-Susitna Borough (681 miles away) at 14.3% and Fairbanks North Star Borough (700 miles away) at 19.4%. Pooled across 19 Alaska counties, 11.5% of reported tests reached that level; across every county in the country with a figure, 23.9%.
Statewide for the same period, Fairbanks North Star Borough reported the highest share (19.4%) and Anchorage Municipality the lowest (3.1%). USGS geology rates 94% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Petersburg Borough, Geology
The ground under Petersburg Borough
PredictedUSGS's geologic map puts all of Petersburg Borough's mapped land in one class: moderate radon potential. The map puts 85.8% of Petersburg Borough in the area it calls Coast Mountains and 7.7% in Coastal Trough. USGS gives both a radon index of 9, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Coast Mountains | Ultramafic through felsic intrusives, Mesozoic mafic volcanic rocks, Mesozoic and Paleozoic sedimentary rocks, schist, gneiss, marble, amphibolite, pelite. | Moderate | 9 | 85.8% |
| Coastal Trough | marine and continental sedimentary rocks; Tertiary volcanic rocks | Moderate | 9 | 7.7% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Petersburg Borough beside the ground around it
Petersburg Borough has more moderate-potential ground than Alaska as a whole: 93.5% of its land against 79.2%. Of the 3 boroughs and census areas that border it, none has as large a share of moderate-potential ground; Wrangell City and Borough comes nearest at 93.1%.
The map rates the ground, not the air in any home.
Local help
Petersburg Borough, Local resources
Radon testing and mitigation in Petersburg Borough
- Alaska's radon programAlaska Division of Geological & Geophysical SurveysAlaska's radon program answers questions about testing, mitigation and the rules in Alaska.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsAsk the program whether it has free or discounted kits, or compare kits you can buy.
- Compare kits
- See the Alaska directoryNo professionals are listed in Alaska yet. The state program can point you to registered testers and mitigators.
What Alaska's program says
- Phone
- 907-269-6401
- paul.goodfellow@alaska.gov
What it means
Petersburg Borough, Questions
Questions about radon in Petersburg Borough
Are radon levels high in Petersburg Borough?
In 2022, 0.0% of the radon tests reported to CDC for Petersburg Borough, Alaska were at or above 4 pCi/L, and the median reported pre-mitigation result was 0.2 pCi/L. Of the 3 nearest counties with a figure, within 700 miles, the share of tests at or above 4 pCi/L runs from 3.1% to 19.4%.
Which counties border Petersburg Borough?
Petersburg Borough borders 3 boroughs and census areas: Prince of Wales-Hyder Census Area, Wrangell City and Borough and Hoonah-Angoon Census Area.
Products
Petersburg Borough, Products
Testing a home in Petersburg Borough
No CDC figure names Petersburg Borough; the nearest county with one, Anchorage Municipality (637 miles away), reported 3.1% of its tests at or above 4 pCi/L in 2022, the only reading nearby until a test of this home. A short-term kit (2 to 90 days) is the quick first check for a home in Petersburg Borough; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
MonitorAEGTEST
HOUND-3699 radon monitor with a 2.1-inch touchscreen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
First reading: Within 1 hour
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Petersburg Borough, Bordering boroughs and census areas
Boroughs and census areas bordering Petersburg Borough
Calculated by Radon4110.0%at or above 4 pCi/L
Median 0.4 pCi/L · 1 test
0.0%at or above 4 pCi/L
Median 0.6 pCi/L · 4 tests
0.0%at or above 4 pCi/L
Median 0.4 pCi/L · 1 test
Petersburg Borough, Cities and towns
Cities and towns in Petersburg Borough
Petersburg Borough's population has barely moved since 2020: 3,394 residents on July 1, 2025 against 3,397 then, by the Census Bureau's estimates. Spread over its land, that is 1.2 people to the square mile. Kupreanof, its one incorporated place, has 18 residents, 0.5% of the total. CDC's 1 reported test for 2022 work out to 0.3 per 1,000 residents (2025 estimate), close to Alaska's 0.4.
Kupreanof is the one incorporated place here; CDC publishes no figure by town, so it reads Petersburg Borough's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Kupreanof | 18 | −5.3% | 0.5% |
One incorporated place, as listed in the U.S. Census Bureau’s 2020 place reference files. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025).
Petersburg Borough, Homes
Homes in Petersburg Borough
Of Petersburg Borough's 1,871 homes, 72% are detached houses, against 63% across Alaska; 10% are in buildings of five or more homes. Half of its homes were built before 1980, close to Alaska's 1985: 28% date from before 1960 and 13% from 2000 or later. 71% of occupied homes are lived in by their owner (Alaska: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Petersburg Borough | Alaska |
|---|---|---|
| Housing units | 1,871 | 327,610 |
| Detached houses | 72% | 63% |
| In buildings of 5 or more | 10% | 12% |
| Mobile homes | 9% | 4% |
| Built before 1960 | 28% | 8% |
| Built since 2000 | 13% | 25% |
| Middle year built | 1980 | 1985 |
| Owner-occupied | 71% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.