Short-term kit
Radon Short Term Test Kit short-term charcoal radon test kit, lab fee included
- Lab fee included
Method: Charcoal
In home: 2 to 7 days
Locations and reports
Radon Levels in Terrebonne Parish, Louisiana
EPA puts Terrebonne Parish in Zone 3, its lowest radon zone, and most reported tests there come back low, though 0.0% of 60 (2020) reached 4 pCi/L. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
0.0%
0.8 pts below LA
- Terrebonne Parish
- 0.0%
- Louisiana
- 0.8%
60 tests, 2020
Median result
0.3pCi/L
Below action level
- Terrebonne Parish
- 0.3 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2020
Tests reported
60
11th of 13 by tests
- Terrebonne Parish
- 60
- Jefferson Parish
- 339
Reported to CDC before any fix, 2020
EPA radon zone
Zone 3
Lower potential
- 1
- 2
- Zone 3
1 highest, 3 lowest
EPA predicts under 2 pCi/L indoors
Rank in Louisiana
3 of 13
Top quarter
- Terrebonne Parish
- 0.0%
- Lafayette Parish
- 19.0%
By share, of 13 with 30+ tests
Read a result for Terrebonne Parish
Starts at Terrebonne Parish's median, 0.3 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 0.3 pCi/L
Below 2 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is below 2 pCi/L, the level at which EPA says a fix should be considered. Terrebonne Parish's median reported result, 2020.
The data
Terrebonne Parish, At a glance
Terrebonne Parish at a glance
Predicted: EPA radon zone
EPA Zone 3: lower predicted potential
USGS geologic potential: Low across 83% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Terrebonne Parish, 2020
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2015 | 0.0% |
| 2016 | 0.0% |
| 2018 | 0.0% |
| 2020 | 0.0% |
2020: 0.0%. Across these years the share ran from 0.0% to 0.0%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 60 tests reported to CDC for Terrebonne Parish over 2020, many from homes being sold or already suspected of a problem: they describe the parish's reported tests, not this house.
Measured: CDC tracking data. Figure above: 2020. Measured data period: 2005 to 2020 (every CDC figure on file).
Terrebonne Parish, Compared
Terrebonne Parish radon figures, compared
Calculated by Radon411Only 0 of 60 radon tests reported for Terrebonne Parish in 2020 reached 4 pCi/L (0.0%). The median result, 0.3 pCi/L, sits below 2, well under EPA's 4 pCi/L action level, and the top reported result was 1.2 pCi/L.
Across 18 Louisiana counties pooled together, 0.8% of tests reached that level, so Terrebonne Parish runs 0.8 points below its state. Against the national pool of 25.5%, the gap is 25.5 points lower. Its place in the state: 3rd of 13 Louisiana counties with 30 or more tests for the same period.
Zone 3 on EPA's map (predicted average under 2 pCi/L) and a 0.0% share point the same way here.
Below the action level, 60 tests (100.0%) came in under 2 pCi/L, against 94.9% statewide, and 0 tests (0.0%) fell between 2 and 4, against 4.2% statewide. USGS geology rates 83% of the county's land low radon potential.
The busiest year on file was 2020, with 60 tests reported; the quietest, 2018, had 3.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Terrebonne Parish, Geology
The ground under Terrebonne Parish
PredictedUSGS's geologic map puts all of Terrebonne Parish's mapped land in one class: low radon potential. 82.9% of it lies in the area the map calls Delta, to which USGS gives a radon index of 6, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Delta | Alluvium and marsh. | Low | 6 | 82.9% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Terrebonne Parish beside the ground around it
Neither Terrebonne Parish nor Louisiana as a whole has any land USGS rates above low potential. None of the 3 parishes that border it has any moderate-potential ground either.
The map rates the ground, not the air in any home.
Local help
Terrebonne Parish, Local resources
Radon testing and mitigation in Terrebonne Parish
- Louisiana's radon programLouisiana Department of Environmental QualityLouisiana's radon program answers questions about testing, mitigation and the rules in Louisiana.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 Louisiana directoryNo professionals are listed in Louisiana yet. The state program can point you to registered testers and mitigators.
What it means
Terrebonne Parish, Questions
Questions about radon in Terrebonne Parish
Are radon levels high in Terrebonne Parish?
In 2020, 0.0% of the radon tests reported to CDC for Terrebonne Parish, Louisiana were at or above 4 pCi/L, and the median reported pre-mitigation result was 0.3 pCi/L. Of 13 Louisiana counties with 30 or more tests for the same period, 2 reported a higher share; pooled, the state comes to 0.8%.
Which counties border Terrebonne Parish?
Terrebonne Parish borders 3 parishes: Lafourche Parish, Assumption Parish and St. Mary Parish.
Products
Terrebonne Parish, Products
Testing a home in Terrebonne Parish
In Terrebonne Parish, 0.0% of 60 tests reported to CDC in 2020 reached 4 pCi/L, against 0.8% pooled across Louisiana. Zone 3 is the lowest label, yet homes at or above 4 pCi/L occur in every zone: a short-term kit (2 to 90 days) is the quick first check in Terrebonne Parish.
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
Monitor
Corentium Home battery digital radon detector
- C-NRPP 2024/25: Approved
- Battery
- Screen
Method: Alpha spectrometry
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Terrebonne Parish, Bordering parishes
Parishes bordering Terrebonne Parish
Calculated by Radon411- Radon levels in Lafourche ParishEPA zone 3
0.0%at or above 4 pCi/L
Median 0.8 pCi/L · 3 tests · 0.0 points above Terrebonne Parish
- Radon levels in Assumption ParishEPA zone 3
No CDC figure for 2020; its page reads it against its own neighbours.
- Radon levels in St. Mary ParishEPA zone 3
No CDC figure for 2020; its page reads it against its own neighbours.
Terrebonne Parish, Cities and towns
Cities and towns in Terrebonne Parish
About 104,163 people live in Terrebonne Parish by the Census Bureau's estimate for July 1, 2025, 5,252 fewer than in 2020 (−4.8%). That works out to 85 people per square mile of land. Houma, its one incorporated place, has 31,735 residents, 30.5% of the total. CDC's 60 reported tests for 2020 work out to 0.6 per 1,000 residents (2025 estimate), close to Louisiana's 0.4.
Houma is the one incorporated place here; CDC publishes no figure by town, so it reads Terrebonne Parish's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Houma | 31,735 | −4.8% | 30.5% |
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).
Terrebonne Parish, Homes
Homes in Terrebonne Parish
Of Terrebonne Parish's 47,236 homes, 71% are detached houses, against 65% across Louisiana; 15% are mobile homes. Half of its homes were built before 1982, close to Louisiana's 1982: 17% date from before 1960 and 27% from 2000 or later. 74% of occupied homes are lived in by their owner (Louisiana: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Terrebonne Parish | Louisiana |
|---|---|---|
| Housing units | 47,236 | 2,094,002 |
| Detached houses | 71% | 65% |
| In buildings of 5 or more | 9% | 11% |
| Mobile homes | 15% | 13% |
| Built before 1960 | 17% | 19% |
| Built since 2000 | 27% | 27% |
| Middle year built | 1982 | 1982 |
| Owner-occupied | 74% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.