Radon in St. Mary Parish, Louisiana
St. Mary Parish, Louisiana, is in EPA radon Zone 3: predicted average indoor radon screening level less than 2 pCi/L (low potential). No laboratory test results are on file for this county (no tests reported, or too few to publish).
Radon test results in St. Mary Parish
No radon test results are on file for St. Mary Parish. Its EPA zone is Zone 3.
Test results describe buildings whose owners chose to test and whose results reached the lab or agency, not a random sample; small counts swing widely. State and US shares are computed from county counts and percents. The laboratory data comes from national radon testing laboratories and supplements EPA's zone map.
Radon in nearby counties
| County | EPA zone | Lab tests | 4 pCi/L or more |
|---|---|---|---|
| Iberia Parish, LA | Zone 3 | 1 | 0% |
| Assumption Parish, LA | Zone 3 | n/a | n/a |
| St. Martin Parish, LA | Zone 3 | 1 | 0% |
| Terrebonne Parish, LA | Zone 3 | 5 | 0% |
| Iberville Parish, LA | Zone 3 | 1 | 0% |
| St. James Parish, LA | Zone 3 | n/a | n/a |
The six counties with the nearest centers.
What to do about radon in St. Mary Parish
Test the building. EPA recommends fixing a home at 4 pCi/L or more and considering a fix between 2 and 4 pCi/L, and says there is no known safe level of exposure. Louisiana's state radon program can point you to testers and test kits.
Buying here? The Environmental Records Report lists this county's radon zone and test results with the flood zone, mapped faults, power lines and federal contamination records near the address.
Radon in St. Mary Parish: questions
What is the radon level in St. Mary Parish?
No laboratory results are on file for St. Mary Parish. The county's EPA zone is Zone 3. Only a test of the building gives its level.
Is St. Mary Parish in radon Zone 1?
No. EPA's 1993 map puts St. Mary Parish in Zone 3 (predicted average indoor radon screening level less than 2 pCi/L (low potential)). EPA says homes in every zone can have high radon and should be tested.
Should I test for radon in St. Mary Parish?
Yes. EPA recommends testing every home whatever its zone: "This map should not be used to determine if individual homes need to be tested." Fix the home at 4 pCi/L or more and consider a fix between 2 and 4 pCi/L; EPA says there is no known safe level of radon exposure.
More for St. Mary Parish
- St. Mary Parish loan limitsThis year's FHFA conforming, FHA and VA county loan limits for 1 to 4 unit homes, from FHFA's and HUD's official files.
- St. Mary Parish fair market rentHUD Fair Market Rents for studios to 4 bedrooms, the voucher payment standard range and the change from last year.
- St. Mary Parish property tax rateEffective property tax rate from Census survey data: median taxes paid against median home value, ranked in the state.
- Environmental records reportSuperfund, hazardous waste, leaking tank and brownfield sites near any St. Mary Parish address, with distances and a site map. A records search, not a Phase I.
- Superfund sites in LouisianaEvery EPA Superfund site in Louisiana with its status, county and a map, refreshed nightly from federal records.
- USDA eligibility map: LouisianaHow much of each Louisiana county is in a USDA-eligible rural area, the towns mapped ineligible, and a free address check.
- Opportunity zones in LouisianaEvery designated Opportunity Zone tract in Louisiana by county, from the IRS list, and the tracts eligible for the 2027 round.
- Census tract lookupThe census tract of any St. Mary Parish address with its FFIEC income level and HUD Qualified Census Tract and DDA status.
Other free hazard lookups
- Fault lines near an addressUSGS-mapped earthquake faults within 5 miles, their age and slip rate, and the USGS seismic hazard value.
- Power lines near an addressHigh-voltage transmission lines within 1 mile from federal maps, with voltage and distance.
- Flood zone lookupThe FEMA flood zone mapped at any US address. Not an official flood zone determination.
- Superfund sites near an addressThe nearest EPA Superfund (NPL) sites and their status.
All of these, plus wetlands, FEMA hazard ratings and the federal contamination lists, are in the Environmental Records Report for any US address ($29).
Radon in every Louisiana county · Radon map of every state
Data compiled 2026-10-20. County FIPS 22101. County-level screening information, not a radon measurement of any building.