Short-term kitFirst Alert
RD1 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 2 to 4 days
Locations and reports
Radon Levels in St. Martin Parish, Louisiana
EPA puts St. Martin Parish in Zone 3, its lowest radon zone, and only 3 radon tests from it are on file with CDC (2017). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Nearest county
0.0%
East Baton Rouge Parish, 42 miles
- East Baton Rouge Parish
- 0.0%
- Louisiana
- 2.8%
Share at 4+ pCi/L, 48 tests, 2006 to 2015
Ground above low
None
Level with Louisiana
- St. Martin Parish
- 0.0%
- Louisiana
- 0.0%
Share of land USGS rates moderate or high potential
Tests reported
6
Too few for a share
- St. Martin Parish
- 6
- Needed
- 30
2016
EPA radon zone
Zone 3
Lower potential
- 1
- 2
- Zone 3
1 highest, 3 lowest
EPA predicts under 2 pCi/L indoors
Read a result for St. Martin Parish
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
St. Martin Parish, At a glance
St. Martin Parish at a glance
Predicted: EPA radon zone
EPA Zone 3: lower predicted potential
USGS geologic potential: Low across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for St. Martin Parish, 2017
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2016 | 0.0% |
| 2017 | 0.0% |
2017: 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
Only 3 tests were reported to CDC for St. Martin Parish over 2017, and tests are often run on homes being sold or already suspected of a problem: so few describe neither the parish nor this house.
Measured: CDC tracking data. Figure above: 2017. Measured data period: 2006 to 2017 (every CDC figure on file).
St. Martin Parish, Compared
St. Martin Parish radon figures, compared
Calculated by Radon411CDC's largest figure for St. Martin Parish rests on 6 tests in 2016, 0 of them at or above 4 pCi/L, so each test moves its share by 16.7 points and no rank or comparison is drawn from it. Results reached as high as 0.8 pCi/L, with a middle value of 0.8 pCi/L.
The nearest counties with a figure are East Baton Rouge Parish (42 miles away) at 0.0%, Tangipahoa Parish (80 miles away) at 0.0% and Jefferson Parish (92 miles away) at 1.5%. Pooled across 37 Louisiana counties, 2.8% of reported tests reached that level; across every county in the country with a figure, 36.3%.
Statewide for the same period, Jefferson Parish reported the highest share (1.5%) and Tangipahoa Parish the lowest (0.0%). EPA's 1993 map puts St. Martin Parish in Zone 3, its lowest label: a predicted county average under 2 pCi/L. USGS geology rates 100% of the county's land low radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
St. Martin Parish, Geology
The ground under St. Martin Parish
PredictedUSGS's geologic map puts all of St. Martin Parish's mapped land in one class: low radon potential. The map puts 65.5% of St. Martin Parish in the area it calls Floodplain and 22.3% in Delta, with one smaller area beside them. USGS gives the first a radon index of 7 and the second 6, both in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Floodplain | Alluvium, marsh, silt, and clay. | Low | 7 | 65.5% |
| Delta | Alluvium and marsh. | Low | 6 | 22.3% |
| Terraces and Prairies | Clay, sandy clay, silt, sand, and some gravel. | Low | 8 | 12.1% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
St. Martin Parish beside the ground around it
Neither St. Martin Parish nor Louisiana as a whole has any land USGS rates above low potential. None of the 7 parishes that border it has any moderate-potential ground either.
The map rates the ground, not the air in any home.
Local help
St. Martin Parish, Local resources
Radon testing and mitigation in St. Martin 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
St. Martin Parish, Questions
Questions about radon in St. Martin Parish
Are radon levels high in St. Martin Parish?
In 2017, 0.0% of the radon tests reported to CDC for St. Martin Parish, Louisiana were at or above 4 pCi/L, and the median reported pre-mitigation result was 0.6 pCi/L. Of the 4 nearest counties with a figure, within 105 miles, the share of tests at or above 4 pCi/L runs from 0.0% to 1.5%.
Which counties border St. Martin Parish?
St. Martin Parish borders 7 parishes: Lafayette Parish, St. Landry Parish, Iberia Parish, Iberville Parish, Pointe Coupee Parish, St. Mary Parish and Assumption Parish.
Products
St. Martin Parish, Products
Testing a home in St. Martin Parish
No CDC figure names St. Martin Parish; the nearest county with one, East Baton Rouge Parish (42 miles away), reported 0.0% of its tests at or above 4 pCi/L over the 2006 to 2015 laboratory totals, the only reading nearby until a test of this home. 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 St. Martin 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
View Plus radon and air quality monitor
- C-NRPP 2024/25: Approved
- Battery
- Wi-Fi, Bluetooth
- Screen, app
Method: Alpha spectrometry
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
St. Martin Parish, Bordering parishes
Parishes bordering St. Martin Parish
Calculated by Radon411- Radon levels in St. Landry ParishEPA zone 3
25.0%at or above 4 pCi/L
Median 0.8 pCi/L · 4 tests
- Radon levels in Lafayette ParishEPA zone 3
4.8%at or above 4 pCi/L
Median 0.7 pCi/L · 21 tests
- Radon levels in Iberia ParishEPA zone 3
0.0%at or above 4 pCi/L
Median 2.0 pCi/L · 4 tests
- Radon levels in Iberville ParishEPA zone 3
0.0%at or above 4 pCi/L
Median 0.6 pCi/L · 1 test
- Radon levels in Pointe Coupee ParishEPA zone 3
No CDC figure for 2006 to 2015; its page reads it against its own neighbours.
- Radon levels in St. Mary ParishEPA zone 3
No CDC figure for 2006 to 2015; its page reads it against its own neighbours.
- Radon levels in Assumption ParishEPA zone 3
No CDC figure for 2006 to 2015; its page reads it against its own neighbours.
St. Martin Parish, Cities and towns
Cities and towns in St. Martin Parish
About 51,106 people live in St. Martin Parish by the Census Bureau's estimate for July 1, 2025, 510 fewer than in 2020 (−1.0%). That works out to 69 people per square mile of land. Broussard, the largest place on its list (15,799 residents in all), extends beyond St. Martin Parish, so no share of the total is worked out for it. Reported testing is thin here: 6 tests over 2016, or 0.1 for every 1,000 residents (2025 estimate), where Louisiana as a whole comes to 0.3.
From Broussard to Parks, CDC publishes no figure by town: each reads St. Martin Parish's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Broussardextends beyond St. Martin Parish | 15,799 | +16.8% | Counted whole |
| Morgan Cityextends beyond St. Martin Parish | 10,757 | −5.7% | Counted whole |
| Breaux Bridge | 7,652 | +2.3% | 15.0% |
| St. Martinville | 5,229 | −3.0% | 10.2% |
| Henderson | 1,594 | −0.8% | 3.1% |
| Arnaudvilleextends beyond St. Martin Parish | 991 | −0.9% | Counted whole |
| Parks | 671 | −2.3% | 1.3% |
7 incorporated places, 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). A place that extends beyond St. Martin Parish is counted whole, so it has no share.
St. Martin Parish, Homes
Homes in St. Martin Parish
Of St. Martin Parish's 23,704 homes, 69% are detached houses, against 65% across Louisiana; 26% are mobile homes. Half of its homes were built before 1987, close to Louisiana's 1982: 16% date from before 1960 and 31% from 2000 or later. Owners live in 79% of the occupied homes (Louisiana: 67%), so for most households a test and a fix are their own to order.
| Homes | St. Martin Parish | Louisiana |
|---|---|---|
| Housing units | 23,704 | 2,094,002 |
| Detached houses | 69% | 65% |
| In buildings of 5 or more | 1% | 11% |
| Mobile homes | 26% | 13% |
| Built before 1960 | 16% | 19% |
| Built since 2000 | 31% | 27% |
| Middle year built | 1987 | 1982 |
| Owner-occupied | 79% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.