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Louisiana Radon Map and Levels by Parish

EPA puts all of Louisiana's classified parishes in Zone 3. Homes with elevated levels occur in all three zones, so only a test measures yours.

Data checked By Radon411Methodology

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  • Share at 4+ pCi/L

    3.9%

    20.5 pts below U.S.

    Louisiana
    3.9%
    U.S.
    24.4%

    3,327 tests across 21 parishes, 2021

  • Rank among states

    16 of 16

    Ten lowest states

    Louisiana
    3.9%
    Colorado
    47.3%

    By share, every state pooled the same way, 2021

  • Counties in EPA Zone 1

    0 of 64

    None at highest potential

    Zone 1
    0
    Zone 2
    0

    Most parishes sit in Zone 3; Zone 1 is the highest potential

  • Highest parish

    20.1%

    Caddo Parish

    Caddo Parish
    20.1%
    Tangipahoa Parish
    0.0%

    Parishes with 30+ tests, 2021

Read a result for Louisiana

Starts at EPA's action level

4.0pCi/L

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

  1. Under 20 to 1.9 pCi/L
  2. 2 to 4consider a fix
  3. 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. 3.9% of Louisiana's reported tests reached 4 pCi/L, 2021.

Interpret this readingWhat a fix costs

The data

Louisiana, At a glance

Louisiana at a glance

Predicted: EPA radon zone

64 of 64 parishes classified

EPA classifies counties, not states. Of the 64 parishes in Louisiana with a zone, 64 are in Zone 3.

  • Zone 3: Lower predicted potentialless than 2 pCi/L64 of 64 parishes · 100.0%

An EPA radon zone predicts a whole county. It is not intended to determine whether any individual home should be tested: homes with elevated levels occur in all three zones, and EPA recommends testing every home regardless of zone.

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

CDC test figures, parish by parish

CDC publishes Louisiana's radon test figures by parish: 54 of its 64 parishes have one. Each one's share is in the parish list.

How to read these figures

Louisiana, Compared

Louisiana radon figures, compared

Calculated by Radon411
Louisiana, 2021
3.9%
of 3,327 tests at or above 4 pCi/L, pooled
Against the U.S.
−20.5points
24.4% pooled
Rank among the states
16 of 16
1 is the highest share
Parishes with 30 or more tests
14
Highest
20.1%
Caddo Parish
Lowest
0.0%
Tangipahoa Parish

Fewer reported tests reach 4 pCi/L in Louisiana than in most states: 3.9% of 3,327 in 2021, from 21 parishes. Nationally the pooled share is 24.4%: 20.5 points higher than here. Among 16 states pooled the same way it ranks 16th, with New Jersey (10.3%) above it.

Caddo Parish reports the highest share (20.1% of 477 tests) and Tangipahoa Parish the lowest (0.0%); the most tests came from Ascension Parish, 522 of them at 0.0%. EPA's 1993 map puts 0 of its 64 classified parishes in Zone 1; the tests reported since bear that out at 3.9%.

By band, 1 parish at 15% to 30%, 1 parish at 5% to 15%, 12 parishes at under 5%. Year by year (9 years pooled), the share went from 10.5% (2014) to 0.4% (2022), down 10.0 points, with 2014 the highest at 10.5%.

Louisiana ranked among 16 states by pooled share of tests at or above 4 pCi/L, 2021
StateRankParishesTestsAt or above 4 pCi/L
Minnesota6 of 168729,29133.1%
Missouri7 of 16821,65831.8%
Kansas8 of 169669,90931.8%
Vermont9 of 16142,14419.2%
New York10 of 164957018.9%
Alaska11 of 161329818.8%
Oregon12 of 16334,46316.3%
Florida13 of 165516,06615.4%
North Carolina14 of 16826,60314.9%
New Jersey15 of 1621125,53710.3%
Louisiana16 of 16213,3273.9%
Louisiana's highest parishes with 30 or more tests, by share at or above 4 pCi/L, 2021
ParisheRankTestsAt or above 4 pCi/L
Caddo Parish1 of 1447720.1%
Lafayette Parish2 of 1423114.3%
Ascension Parish3 of 145220.0%
West Baton Rouge Parish4 of 144530.0%
East Baton Rouge Parish5 of 144200.0%
Avoyelles Parish6 of 142160.0%
Calcasieu Parish7 of 142160.0%
Rapides Parish8 of 141920.0%
Natchitoches Parish9 of 141680.0%
Ouachita Parish10 of 141590.0%
Louisiana's parishes with 30 or more tests, by their own share at or above 4 pCi/L, 2021
ShareParishesTheir testsFor example
50% or more00None
30% to 50%00None
15% to 30%1477Caddo Parish
5% to 15%1231Lafayette Parish
Under 5%122,589Ascension Parish, West Baton Rouge Parish, East Baton Rouge Parish
Louisiana pooled by year, against the United States
YearParishesTestsAt or above 4 pCi/LUnited StatesChange from the row before
2022122,0220.4%23.9%−3.4 points
2021213,3273.9%24.4%+3.0 points
2020181,7760.8%25.5%−1.2 points
2019232,3612.0%29.0%+1.5 points
2018282,3430.5%29.1%−2.1 points
2017231,6142.6%31.7%+0.6 points
2016211,3472.0%31.2%−5.2 points
2015203757.2%35.5%−3.3 points
20141837210.5%34.9%First on file

Pooled shares: Radon411's sum of CDC's county counts for one period. CDC publishes no state or national figure.

Louisiana, Parishes

Louisiana parishes by EPA zone

Predicted

Louisiana's radon map, then all 64 parishes by EPA's zone, the highest reported share of tests at or above 4 pCi/L first; each has its own report.

Louisiana radon map by parish: EPA radon zones. Map of Louisiana's 64 counties shaded by EPA radon zone: Zone 3 in pale sand. 0 in Zone 1, 0 in Zone 2, 64 in Zone 3.
Louisiana radon map by parishEPA radon zones for Louisiana's counties: 0 counties in Zone 1, 0 counties in Zone 2, 64 counties in Zone 3.A prediction for each county, not a reading of any home; elevated homes occur in all three zones.

The 12 highest in Louisiana, 2021

Zone 3: lower predicted potential64

Local help

Louisiana, Local resources

Local resources in Louisiana

Who to ask in Louisiana: its radon program, test kits and professionals.

What it means

Louisiana, Questions

Questions about radon in Louisiana

Is radon a problem in Louisiana?

EPA's Map of Radon Zones places 0 of the 64 Louisiana parishes it classifies in Zone 1, the highest predicted potential, 0 in Zone 2 and 64 in Zone 3. Pooled from 21 parishes, 3.9% of the 3,327 radon tests reported to CDC in 2021 were at or above 4 pCi/L, 16th of 16 states.

Which Louisiana counties have the highest radon?

Caddo Parish 20.1% (477 tests) leads Louisiana by the share of reported tests at or above 4 pCi/L, 2021, then Lafayette Parish 14.3% (231 tests), Ascension Parish 0.0% (522 tests), West Baton Rouge Parish 0.0% (453 tests), East Baton Rouge Parish 0.0% (420 tests).

Which EPA region is Louisiana in?

Louisiana is in EPA Region 6: South Central.

Products

Louisiana, Products

Testing a home in Louisiana

3.9% of the 3,327 tests reported to CDC for Louisiana in 2021 reached 4 pCi/L: a short-term kit (2 to 90 days) gives a first answer in days, a long-term test the year-round average. A short-term kit (2 to 90 days) is the quick first check for a home in Louisiana; a long-term test tells the year-round average.

Test kits and monitors3

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Best radon monitors for Louisiana homes, compared

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