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 Adams County, Pennsylvania
EPA puts Adams County in Zone 1, its highest radon zone, and 39.7% of its 852 reported radon tests (2020) were at or above 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
39.7%
9.4 pts above PA
- Adams
- 39.7%
- PA
- 30.3%
852 tests, 2020
Median result
2.8pCi/L
Below action level
- Adams
- 2.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2020
Tests reported
852
24th of 63 by tests
- Adams
- 852
- Montgomery
- 10,508
Reported to CDC before any fix, 2020
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in PA
32 of 63
Middle half
- Adams
- 39.7%
- Perry
- 57.7%
By share, of 63 with 30+ tests
Read a result for Adams County
Starts at Adams County's median, 2.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 2.8 pCi/L
Between 2 and 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is between 2 and 4 pCi/L. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. Adams County's median reported result, 2020.
The data
Adams County, At a glance
Adams County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Adams County in
USGS geologic potential: High across 72% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Adams County, 2020
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 38.7% |
| 2015 | 35.2% |
| 2016 | 41.6% |
| 2017 | 44.9% |
| 2018 | 36.6% |
| 2019 | 40.5% |
| 2020 | 39.7% |
2020: 39.7%. Across these years the share ran from 35.2% to 44.9%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 852 tests reported to CDC for Adams County over 2020, many from homes being sold or already suspected of a problem: they describe the county's reported tests, not this house.
Measured: CDC tracking data. Figure above: 2020. Measured data period: 2005 to 2020 (every CDC figure on file).
Adams County, Compared
Adams County radon figures, compared
Calculated by Radon411In Adams County, about 4 in 10 reported tests in 2020 (338 of 852) were at or above EPA's action level. Against the national pool of 25.5%, the gap is 14.2 points higher. Across 67 Pennsylvania counties pooled together, 30.3% of tests reached that level, so Adams County runs 9.4 points above its state.
Of 3 neighbours with a figure, all 3 reported a larger share at or above 4 pCi/L; the spread is 42.6% (Franklin County) to 46.8% (York County). By share, Adams County is 32nd of 63 Pennsylvania counties with 30 or more tests for the same period.
Year by year, 2014 opened at 38.7% and 2020 closed at 39.7% (about level), with 2017 the high at 44.9%. Half the tests came in under 2.8 pCi/L and half over it; the single highest reached 119.0 pCi/L. Below the action level, 317 tests (37.2%) came in under 2 pCi/L, against 44.3% statewide, and 197 tests (23.1%) fell between 2 and 4, against 25.4% statewide.
Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 39.7% share point the same way here. USGS geology rates 72% of the county's land high radon potential.
The busiest year on file was 2015, with 1,026 tests reported; the quietest, 2014, had 713.
Adams CountyPennsylvania, pooled
39.7% % of tests30.3% % of tests
| Year | Tests | Adams County, at or above 4 pCi/L | Pennsylvania, pooled |
|---|---|---|---|
| 2014 | 713 | 38.7% | 36.1% |
| 2015 | 1,026 | 35.2% | 37.8% |
| 2016 | 936 | 41.6% | 34.4% |
| 2017 | 847 | 44.9% | 35.1% |
| 2018 | 868 | 36.6% | 30.5% |
| 2019 | 989 | 40.5% | 31.4% |
| 2020 | 852 | 39.7% | 30.3% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Adams County, State data
Pennsylvania's own radon test data
MeasuredWhat Pennsylvania's own agencies publish about radon tests in Adams County, with their period. These are not CDC's figures and are never added to them.
MeasuredState figures, not CDC's
What Pennsylvania DEP reports for the ZIP codes in Adams County
Pennsylvania DEP publishes its figures by ZIP code, not by county. These are the 18 ZIP codes that lie wholly or partly in Adams County, each with the state's own figures for it. Period: Period not stated by DEP.
| ZIP code | What the state reports |
|---|---|
| 17019 | Basement: average 7.6 pCi/L, 3,744 tests; First floor: average 3.7 pCi/L, 481 tests |
| 17222 | Basement: average 7.7 pCi/L, 1,614 tests; First floor: average 4.6 pCi/L, 227 tests |
| 17301 | Basement: average 4.5 pCi/L, 326 tests; First floor: figures not shown |
| 17303 | Basement: average 4.9 pCi/L, 40 tests; First floor: figures not shown |
| 17304 | Basement: average 13.9 pCi/L, 151 tests; First floor: figures not shown |
| 17306 | Basement: average 9.6 pCi/L, 33 tests; First floor: figures not shown |
| 17307 | Basement: average 8.5 pCi/L, 382 tests; First floor: average 4.8 pCi/L, 68 tests |
| 17316 | Basement: average 5.3 pCi/L, 910 tests; First floor: average 2.6 pCi/L, 106 tests |
| 17320 | Basement: average 8.6 pCi/L, 947 tests; First floor: average 5.1 pCi/L, 111 tests |
| 17324 | Basement: average 17.9 pCi/L, 391 tests; First floor: average 6.5 pCi/L, 86 tests |
| 17325 | Basement: average 5.0 pCi/L, 2,978 tests; First floor: average 2.0 pCi/L, 899 tests |
| 17331 | Basement: average 11.0 pCi/L, 7,900 tests; First floor: average 5.7 pCi/L, 770 tests |
| 17340 | Basement: average 9.4 pCi/L, 1,299 tests; First floor: average 3.6 pCi/L, 103 tests |
| 17343 | Basement: figures not shown |
| 17344 | Basement: average 5.9 pCi/L, 101 tests; First floor: figures not shown |
| 17350 | Basement: average 5.1 pCi/L, 727 tests; First floor: average 2.1 pCi/L, 133 tests |
| 17353 | Basement: average 12.8 pCi/L, 321 tests; First floor: average 7.6 pCi/L, 53 tests |
| 17372 | Basement: average 9.1 pCi/L, 297 tests; First floor: average 2.8 pCi/L, 40 tests |
- DEP's report gives the number of tests, the highest result and the average result for each floor tested; it states no period.
- DEP says the smartest thing to do is to test your home for radon, no matter where you live.
- A ZIP code that crosses the county line is listed whole; its figures cover all of it.
Measured: Pennsylvania DEP data, Period not stated by DEP.
Adams County, Geology
The ground under Adams County
PredictedUSGS's geologic map splits Adams County: 72.3% of its land is high radon potential and 27.7% low. The map puts 64.7% of Adams County in the area it calls Newark Basin and 27.7% in Blue Ridge Gettysburg Basin, with one smaller area beside them. USGS gives the first a radon index of 12, in the high band (12 to 17), and the second 8, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Newark Basin | Gray shale and fluvial sandstone. | High | 12 | 64.7% |
| Blue Ridge Gettysburg Basin | Metasedimentary and metavolcanic rocks. | Low | 8 | 27.7% |
| Piedmiont Upland | Granitic gneiss, graphitic gneiss, quartz monzonite, quartz monzonite gneiss, granodiorite, and granodiorite gneiss. | High | 14 | 7.6% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Adams County beside the ground around it
On high-potential ground Adams County is close to Pennsylvania as a whole: 72.3% of its land against 70.4%. Of the 5 counties that border it, 4 have more high-potential ground, York County the most at 99.2%.
The map rates the ground, not the air in any home.
Local help
Adams County, Local resources
Radon testing and mitigation in Adams County
Listed radon businesses with an address in Adams County:
- Radon DivisionRadon Division, run by Department of Environmental Protection, licenses or certifies radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Pennsylvania.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
Through an EPA-funded program, hospitals give parents of newborn children a packet of information which includes a coupon for a free radon test kit from the DEP.
- Compare kits
- Professionals in Pennsylvania151 professionals are listed in Pennsylvania.
Listed radon professionals by town: Gettysburg, East Berlin
What Pennsylvania's program says
- Phone
- 800-237-2366
- Licensing of radon professionals
The Radon Certification Act requires DEP to establish by regulation, a certification program for persons conducting radon gas and radon progeny testing, laboratory analysis and mitigation of radon contamination in buildings.
What it means
Adams County, Questions
Questions about radon in Adams County
Are radon levels high in Adams County?
In 2020, 39.7% of the radon tests reported to CDC for Adams County, Pennsylvania were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.8 pCi/L. Of 63 Pennsylvania counties with 30 or more tests for the same period, 31 reported a higher share; pooled, the state comes to 30.3%.
Which counties border Adams County?
Adams County borders 5 counties: Cumberland County, PA, York County, PA, Franklin County, PA, Carroll County, MD and Frederick County, MD.
Products
Adams County, Products
Testing a home in Adams County
In Adams County, 39.7% of 852 tests reported to CDC in 2020 reached 4 pCi/L, against 30.3% pooled across Pennsylvania. In Zone 1 the year-round level in Adams 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
MonitorX-Sense
XR0A-SR battery digital radon detector with a screen
- C-NRPP 2024/25: Not included
- Battery
- Screen
Method: Alpha spectrometry
First reading: Within 24 hours
Short-term kit
RA100 short-term liquid scintillation radon test kit
- Lab fee extra
Method: Liquid scintillation
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Adams County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Adams County
Explore
Adams County, Bordering counties
Counties bordering Adams County
Calculated by Radon411- Radon levels in York County, PAEPA zone 1
46.8%at or above 4 pCi/L
Median 3.6 pCi/L · 3,679 tests · 7.1 points above Adams County
- Radon levels in Cumberland County, PAEPA zone 1
43.6%at or above 4 pCi/L
Median 3.1 pCi/L · 2,950 tests · 3.9 points above Adams County
- Radon levels in Franklin County, PAEPA zone 1
42.6%at or above 4 pCi/L
Median 3.1 pCi/L · 1,059 tests · 2.9 points above Adams County
- Radon levels in Carroll County, MDEPA zone 1
No CDC figure for 2020; its page reads it against its own neighbours.
- Radon levels in Frederick County, MDEPA zone 1
No CDC figure for 2020; its page reads it against its own neighbours.
Adams County, Cities and towns
Cities and towns in Adams County
The Census Bureau estimates 107,594 residents in Adams County for July 1, 2025, 3,780 more than in 2020 (+3.6%). That works out to 207 people per square mile of land. No town dominates: Gettysburg, the largest, has 8,365 residents, 7.8% of the total. Together its 13 incorporated places hold 28.7% of those residents; the other 71.3% live outside any of them. CDC's 852 reported tests for 2020 work out to 7.9 per 1,000 residents (2025 estimate), close to Pennsylvania's 7.2.
From Gettysburg to Fairfield, CDC publishes no figure by town: each reads Adams County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Gettysburg | 8,365 | +17.7% | 7.8% |
| Littlestown | 4,895 | +2.5% | 4.5% |
| Carroll Valley | 4,051 | +2.7% | 3.8% |
| McSherrystown | 3,150 | +2.4% | 2.9% |
| New Oxford | 1,912 | +2.6% | 1.8% |
| Bonneauville | 1,802 | +2.5% | 1.7% |
| East Berlin | 1,582 | +2.4% | 1.5% |
| Biglerville | 1,240 | +2.2% | 1.2% |
| Abbottstown | 1,048 | +2.6% | 1.0% |
| Arendtsville | 890 | +2.7% | 0.8% |
| Bendersville | 757 | +2.6% | 0.7% |
| York Springs | 699 | +2.9% | 0.6% |
- Fairfield
13 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).
Adams County, Homes
Homes in Adams County
Of Adams County's 43,377 homes, 75% are detached houses, against 57% across Pennsylvania; 6% are mobile homes. Much of Adams County is recent building: 22% of its homes have gone up since 2000 and the middle year built is 1980, against 1965 for Pennsylvania. Owners live in 79% of the occupied homes (Pennsylvania: 69%), so for most households a test and a fix are their own to order.
| Homes | Adams County | Pennsylvania |
|---|---|---|
| Housing units | 43,377 | 5,779,663 |
| Detached houses | 75% | 57% |
| In buildings of 5 or more | 4% | 13% |
| Mobile homes | 6% | 4% |
| Built before 1960 | 30% | 45% |
| Built since 2000 | 22% | 14% |
| Middle year built | 1980 | 1965 |
| Owner-occupied | 79% | 69% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.