Long-term kit
RL416 long-term radon test kit, lab fee included
- Lab fee included
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in Rio Arriba County, New Mexico
EPA puts Rio Arriba County in Zone 1, its highest radon zone, and only 14 radon tests from it are on file with CDC (2008 to 2017, laboratory totals). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Highest bordering
71.9%
Taos County
- Taos
- 71.9%
- Sandoval
- 24.7%
6 of 8 neighbours have 30+ tests, 2006 to 2015
Nearest county
38.3%
Los Alamos County, 49 miles
- Los Alamos
- 38.3%
- New Mexico
- 30.3%
Share at 4+ pCi/L, 94 tests, 2006 to 2015
Ground above low
100.0%
7.4 pts above New Mexico
- Rio Arriba
- 100.0%
- New Mexico
- 92.6%
Share of land USGS rates moderate or high potential
Tests reported
23
Too few for a share
- Rio Arriba
- 23
- Needed
- 30
2005 to 2014, laboratory
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Read a result for Rio Arriba County
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
Rio Arriba County, At a glance
Rio Arriba County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Rio Arriba County in
USGS geologic potential: Moderate across 62% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Rio Arriba County, 2008 to 2017, laboratory
CDC holds 14 reported tests for Rio Arriba County over the 2008 to 2017 laboratory totals, with a median of 3.5 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Rio Arriba County beside the counties around it is how this page reads it.
What these figures count
Only 14 tests were reported to CDC for Rio Arriba County over 2008 to 2017 (laboratory totals), and tests are often run on homes being sold or already suspected of a problem: so few describe neither the county nor this house.
Measured: CDC tracking data. Figure above: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).
Rio Arriba County, Compared
Rio Arriba County radon figures, compared
Calculated by Radon411CDC's largest figure for Rio Arriba County rests on 23 tests over the 2005 to 2014 laboratory totals, 10 of them at or above 4 pCi/L, so each test moves its share by 4.3 points and no rank or comparison is drawn from it. Results reached as high as 13.9 pCi/L, with a middle value of 2.2 pCi/L.
Of the counties bordering it, 6 have a figure over the 2006 to 2015 laboratory totals: Taos County reported the largest share at or above 4 pCi/L, 71.9%, and Sandoval County the smallest, 24.7%, with Los Alamos County at 38.3%, Archuleta County, CO at 34.3% and Santa Fe County at 32.5% between. Farther out, Bernalillo County (101 miles away) at 25.2%, McKinley County (109 miles away) at 41.9% and San Miguel County (127 miles away) at 44.4% have figures too. Pooled across 30 New Mexico counties, 30.3% of reported tests reached that level; across every county in the country with a figure, 36.3%.
Statewide for the same period, Taos County reported the highest share (71.9%) and Otero County the lowest (10.7%). EPA's 1993 map puts Rio Arriba County in Zone 1, the map's highest label: a predicted county average above 4 pCi/L. USGS geology rates 62% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Rio Arriba County, Geology
The ground under Rio Arriba County
PredictedUSGS's geologic map splits Rio Arriba County: 62.1% of its land is moderate radon potential and 37.9% high. The map puts 57.4% of Rio Arriba County in the area it calls San Juan Basin and 37.2% in Jemez Mountains, with 2 smaller areas beside them. USGS gives the first a radon index of 10, in the moderate band (9 to 11), and the second 12, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| San Juan Basin | Mesozoic marine and non-marine sedimentary rocks including sandstone, siltstone, shale, minor limestone. | Moderate | 10 | 57.4% |
| Jemez Mountains | Tertiary volcanic basalt, andesite, dacite, rhyolite, and rhyolitic tuff. | High | 12 | 37.2% |
| San Juan Volcanic field | Volcanic rocks, rhyolite, tuff, basalt | Moderate | 11 | 4.6% |
| Rocky Mountains (southern extension) | Sandstone, siltstone, shale, volcanic sediments, and valley-fill alluvium. | High | 12 | 0.8% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Rio Arriba County beside the ground around it
Rio Arriba County has more high-potential ground than New Mexico as a whole: 37.9% of its land against 19.2%. Of the 8 counties that border it, 4 have more high-potential ground, Los Alamos County the most at 100%.
The map rates the ground, not the air in any home.
Local help
Rio Arriba County, Local resources
Radon testing and mitigation in Rio Arriba County
- New Mexico Indoor Radon Outreach ProgramNew Mexico Indoor Radon Outreach Program, run by New Mexico Environment Department, does not license radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in New Mexico.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
The New Mexico Environment Department seasonally distributes free radon testing kits to the public on a first-come, first-served basis.
- Compare kits
- See the New Mexico directoryNo professionals are listed in New Mexico yet. The state program can point you to registered testers and mitigators.
What New Mexico's program says
- Phone
- (505) 476-8600
- radon.questions@env.nm.gov
- Licensing of radon professionals
There is not currently a certification program within the state.
What it means
Rio Arriba County, Questions
Questions about radon in Rio Arriba County
Are radon levels high in Rio Arriba County?
Over the 2008 to 2017 laboratory totals, 50.0% of the radon tests reported to CDC for Rio Arriba County, New Mexico were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.5 pCi/L. Of the counties bordering it, 6 have a figure over the 2006 to 2015 laboratory totals: Taos County reported the largest share at or above 4 pCi/L, 71.9%, and Sandoval County the smallest, 24.7%, with Los Alamos County at 38.3%, Archuleta County, CO at 34.3% and Santa Fe County at 32.5% between.
Which counties border Rio Arriba County?
Rio Arriba County borders 8 counties: Los Alamos County, NM, Archuleta County, CO, Conejos County, CO, Taos County, NM, Sandoval County, NM, Santa Fe County, NM, San Juan County, NM and Mora County, NM.
Products
Rio Arriba County, Products
Testing a home in Rio Arriba County
No CDC figure names Rio Arriba County; the nearest county with one, Los Alamos County (49 miles away), reported 38.3% 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. In Zone 1 the year-round level in Rio Arriba County is the one to know: a long-term test (more than 90 days) or a monitor, with a short-term kit for a first answer.
Test kits and monitors3
See every kit and monitor
MonitorAEGTEST
HOUND-1085 palm-sized rechargeable radon detector
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 6 hours
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
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Rio Arriba County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Rio Arriba County
Explore
Rio Arriba County, Bordering counties
Counties bordering Rio Arriba County
Calculated by Radon411- Radon levels in Taos County, NMEPA zone 1
71.9%at or above 4 pCi/L
Median 7.7 pCi/L · 96 tests
- Radon levels in Mora County, NMEPA zone 1
42.9%at or above 4 pCi/L
Median 3.4 pCi/L · 7 tests
- Radon levels in Los Alamos County, NMEPA zone 2
38.3%at or above 4 pCi/L
Median 3.0 pCi/L · 94 tests
- Radon levels in Archuleta County, COEPA zone 2
34.3%at or above 4 pCi/L
Median 2.5 pCi/L · 437 tests
- Radon levels in Santa Fe County, NMEPA zone 1
32.5%at or above 4 pCi/L
Median 2.8 pCi/L · 2,019 tests
- Radon levels in San Juan County, NMEPA zone 2
30.0%at or above 4 pCi/L
Median 2.2 pCi/L · 60 tests
- Radon levels in Sandoval County, NMEPA zone 2
24.7%at or above 4 pCi/L
Median 2.0 pCi/L · 150 tests
- Radon levels in Conejos County, COEPA zone 2
20.0%at or above 4 pCi/L
Median 1.4 pCi/L · 10 tests
Rio Arriba County, Cities and towns
Cities and towns in Rio Arriba County
About 39,832 people live in Rio Arriba County by the Census Bureau's estimate for July 1, 2025, 421 fewer than in 2020 (−1.0%). Spread over its land, that is 6.8 people to the square mile. Española, the largest place on its list (10,458 residents in all), extends beyond Rio Arriba County, so no share of the total is worked out for it. Reported testing is thin here: 23 tests over 2005 to 2014, or 0.6 for every 1,000 residents (2025 estimate), where New Mexico as a whole comes to 2.2.
From Española to Chama, CDC publishes no figure by town: each reads Rio Arriba County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Españolaextends beyond Rio Arriba County | 10,458 | −0.5% | Counted whole |
| Chama | 913 | −0.5% | 2.3% |
2 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 Rio Arriba County is counted whole, so it has no share.
Rio Arriba County, Homes
Homes in Rio Arriba County
Of Rio Arriba County's 19,703 homes, 57% are detached houses, against 65% across New Mexico; 38% are mobile homes. Half of its homes were built before 1983, close to New Mexico's 1984: 16% date from before 1960 and 17% from 2000 or later. Owners live in 78% of the occupied homes (New Mexico: 69%), so for most households a test and a fix are their own to order.
| Homes | Rio Arriba County | New Mexico |
|---|---|---|
| Housing units | 19,703 | 949,524 |
| Detached houses | 57% | 65% |
| In buildings of 5 or more | 1% | 10% |
| Mobile homes | 38% | 16% |
| Built before 1960 | 16% | 17% |
| Built since 2000 | 17% | 24% |
| Middle year built | 1983 | 1984 |
| Owner-occupied | 78% | 69% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.