Category: The Distillery

Massachusetts has meaningful radon risk, with approximately 25-30% of Massachusetts homes estimated to have levels above the EPA action level of 4.0 pCi/L. The state’s geology — including granitic bedrock in western Massachusetts (Berkshires), the Nashoba Zone metamorphic rocks in the MetroWest region, and glacial till overlying uranium-bearing geology across much of the state — creates radon potential across significant portions of the state. The Department of Public Health Radiation Control Program administers radon program resources for Massachusetts residents.

EPA Radon Zone Designation

Zone 1 in western Massachusetts and portions of the MetroWest region, Zone 2 in the greater Boston area and eastern Massachusetts.

Highest-Radon Areas in Massachusetts

Western Massachusetts counties (Hampden, Hampshire, Franklin, Berkshire) overlying Berkshire granitic and metamorphic geology are Zone 1. Worcester County and Middlesex County (MetroWest) are Zone 1 to Zone 2. The greater Boston area (Suffolk, Norfolk, eastern Middlesex) is generally Zone 2.

Radon Contractor Requirements in Massachusetts

NRPP or NRSB national certification. Massachusetts has no separate state radon licensing statute beyond national certification. The Department of Public Health Radiation Control Program maintains radon program resources. Verify contractor credentials at nrpp.info or nrsb.org before engaging any radon professional for measurement or mitigation work.

Radon Disclosure in Massachusetts

Massachusetts’s real estate disclosure law includes the Massachusetts Mandatory Disclosure Law and associated seller’s disclosure form. Known elevated radon conditions are material information that sellers should disclose. Radon testing is standard in Massachusetts real estate transactions.

Testing Resources for Massachusetts Residents

Contact the Department of Public Health Radiation Control Program for the most current list of certified radon professionals, any available test kit programs, and jurisdiction-specific requirements that may have been updated since this page was last reviewed. The national NRPP contractor directory (nrpp.info) is searchable by zip code and provides real-time certification verification.

Frequently Asked Questions

What parts of Massachusetts have the highest radon?

Western Massachusetts (Berkshires, Pioneer Valley) and the MetroWest region of central Massachusetts have the highest radon potential. Greater Boston generally has lower but still meaningful levels. All Massachusetts homes should be tested.

Does Massachusetts require radon contractor certification?

NRPP or NRSB national certification is the operative requirement. No separate Massachusetts licensing statute. Verify credentials at nrpp.info or nrsb.org.

Is radon a concern in Boston or Worcester?

Worcester County is Zone 1 to Zone 2 with significant radon risk. Boston (Suffolk County) is generally Zone 2 with lower but still meaningful potential. Radon testing is recommended throughout Massachusetts.

Boston Metro Radon Context

Greater Boston — Suffolk, Norfolk, and eastern Middlesex counties — is generally Zone 2. This does not mean radon-free: Zone 2 designation reflects lower average concentrations relative to Zone 1, but individual homes throughout the Boston metro can and do test above 4.0 pCi/L. Older Boston-area housing stock (triple-deckers, condo conversions of older homes with concrete block foundations) can have elevated radon even in Zone 2 areas. Cambridge (Middlesex County) and Somerville are Zone 2 with meaningful risk. Waltham and Newton are at the Zone 1/2 boundary.

Worcester and MetroWest Radon

Worcester County is the highest-radon county in Massachusetts — a Zone 1 area driven by Nashoba Zone metamorphic rocks and granitic formations that extend through central Massachusetts. The Worcester metro (Worcester, Shrewsbury, Westborough, Marlborough) shows elevated average radon. The MetroWest region — Framingham, Natick, Milford, Millis — also shows Zone 1 characteristics. Berkshire County (Pittsfield, Lenox) in western Massachusetts overlies Berkshire crystalline geology and is Zone 1 with some of the state’s highest average readings.

Massachusetts Testing Resources

The Massachusetts Department of Public Health (MDPH) Radiation Control Program administers the state radon program. MDPH provides certified contractor information, county-level radon survey data, and educational materials. Massachusetts participates in EPA’s SIRG program. Contact MDPH for the current certified contractor list. The Massachusetts Association of REALTORS provides radon guidance to its members, and radon testing is standard practice in Massachusetts real estate transactions across all county types.

New Hampshire has meaningful radon risk, with approximately 40% of New Hampshire homes estimated to have levels above the EPA action level of 4.0 pCi/L. The state’s geology — including extensive granitic bedrock — the White Mountains and Merrimack Valley granite formations create some of the highest radon potential in New England. New Hampshire’s bedrock is among the most uranium-rich in the eastern United States — creates radon potential across significant portions of the state. The Department of Health and Human Services Radiological Health Section administers radon program resources for New Hampshire residents.

EPA Radon Zone Designation

Zone 1 across most of the state due to extensive granitic geology — New Hampshire sits on the White Mountain Magma Series and Merrimack Valley granite formations.

Highest-Radon Areas in New Hampshire

Hillsborough County (Manchester, Nashua), Merrimack County (Concord), Rockingham County (Portsmouth), and Grafton County (Plymouth, Hanover) all show elevated radon levels. White Mountain counties including Carroll and Grafton have high granitic bedrock radon potential.

Radon Contractor Requirements in New Hampshire

NRPP or NRSB national certification. New Hampshire has no separate state licensing statute. The Department of Health and Human Services Radiological Health Section maintains radon program resources. Verify contractor credentials at nrpp.info or nrsb.org before engaging any radon professional for measurement or mitigation work.

Radon Disclosure in New Hampshire

New Hampshire’s real estate disclosure form requires disclosure of known material defects. Known elevated radon conditions should be disclosed. Radon testing is standard practice in New Hampshire real estate.

Testing Resources for New Hampshire Residents

Contact the Department of Health and Human Services Radiological Health Section for the most current list of certified radon professionals, any available test kit programs, and jurisdiction-specific requirements that may have been updated since this page was last reviewed. The national NRPP contractor directory (nrpp.info) is searchable by zip code and provides real-time certification verification.

Frequently Asked Questions

Is New Hampshire a high-radon state?

Yes. Approximately 40% of NH homes exceed 4.0 pCi/L — one of the highest rates in New England. NH’s granite-rich bedrock is among the most uranium-rich in the eastern U.S. Testing is essential for all NH homes.

Does New Hampshire require radon contractor licensing?

No separate NH licensing statute. NRPP or NRSB national certification is the operative credential. Search nrpp.info for certified New Hampshire contractors.

Is radon a concern in Manchester or Concord?

Yes. Hillsborough County (Manchester) and Merrimack County (Concord) are Zone 1 areas with significant radon potential. Testing is strongly recommended for all southern New Hampshire homes.

Manchester and Nashua Area Radon

Hillsborough County — New Hampshire’s most populous county, containing Manchester and Nashua — is Zone 1 with elevated radon risk throughout the county. Manchester, Nashua, Bedford, and Merrimack sit on Merrimack Valley granite formations with high uranium content. The greater Manchester-Nashua metropolitan area has among the highest residential radon testing rates in the Northeast because real estate agents and buyers in the area have long recognized radon as a standard inspection item. Rockingham County (Portsmouth area, including Salem and Derry) also shows significant Zone 1 radon levels.

White Mountains and Lakes Region Radon

Carroll County (Conway, North Conway, Wolfeboro) in the White Mountains and Lakes Region overlies the Ossipee Ring Dike — a geological formation of particular interest for radon, as ring dikes are associated with alkaline igneous rock that can have elevated uranium content. Grafton County (Plymouth, Hanover — home of Dartmouth College) is Zone 1. The White Mountains granitic formations create consistently high radon potential across the recreational and resort communities of northern New Hampshire. Second homes and vacation properties in these areas should be tested, as seasonal occupancy without testing represents an unacknowledged exposure risk.

New Hampshire Testing Resources

The New Hampshire Department of Health and Human Services (NHDHHS) Radiological Health Section administers the state radon program. NHDHHS provides certified contractor information, county-level radon survey data, and educational resources. New Hampshire participates in EPA’s SIRG program. Contact NHDHHS for the current certified contractor list. New Hampshire has historically had robust radon testing participation rates, and NHDHHS’s survey data provides detailed county-level risk information.

Alaska has meaningful radon risk, with approximately 35% of Alaska homes estimated to have levels above the EPA action level of 4.0 pCi/L. The state’s geology — including granitic basement rock in southeastern Alaska and the Alaska Range, uranium-bearing formations in interior Alaska, and the unique radon dynamics created by permafrost-modified soil gas pathways — creates radon potential across significant portions of the state. The Alaska Division of Environmental Health administers radon program resources for Alaska residents.

EPA Radon Zone Designation

Zone 1 across much of the state due to granitic bedrock, permafrost dynamics, and uranium-bearing geological formations throughout interior and southeastern Alaska.

Highest-Radon Areas in Alaska

Fairbanks (Interior), Anchorage (Southcentral), and Juneau (Southeast) metropolitan areas all have meaningful radon risk. Interior Alaska counties show some of the state’s highest readings due to granitic and uranium-bearing geology.

Radon Contractor Requirements in Alaska

NRPP or NRSB national certification. Alaska has no separate state licensing statute. The Alaska Division of Environmental Health maintains radon program resources. Verify contractor credentials at nrpp.info or nrsb.org before engaging any radon professional for measurement or mitigation work.

Radon Disclosure in Alaska

Alaska has no radon-specific disclosure statute. General material defect disclosure obligations apply to known elevated radon conditions.

Testing Resources for Alaska Residents

Contact the Alaska Division of Environmental Health for the most current list of certified radon professionals, any available test kit programs, and jurisdiction-specific requirements that may have been updated since this page was last reviewed. The national NRPP contractor directory (nrpp.info) is searchable by zip code and provides real-time certification verification.

Frequently Asked Questions

Does Alaska have a radon problem?

Yes. Approximately 35% of Alaska homes exceed 4.0 pCi/L. Interior Alaska (Fairbanks area) has the highest radon potential due to granitic and uranium-bearing geology. All Alaska homeowners should test.

Does Alaska require radon contractor licensing?

No separate Alaska licensing statute. NRPP or NRSB national certification is the operative credential. Search nrpp.info for certified Alaska contractors.

Is radon a concern in Fairbanks or Anchorage?

Yes. The Fairbanks North Star Borough (interior Alaska) has elevated radon potential. Anchorage has moderate to elevated risk. Testing is recommended throughout Alaska regardless of location.

Interior Alaska Radon Risk

Interior Alaska — particularly the Fairbanks North Star Borough — has the state’s highest average radon concentrations. Fairbanks sits on geological formations including granite, schist, and mineralized zones associated with historic gold mining. The Fairbanks area’s extreme temperature differential (interior Alaska winters can reach -50°F) creates an unusually powerful stack effect — homes are tightly sealed for energy efficiency, and the massive indoor-outdoor temperature gap drives strong radon draw from the sub-slab zone. The combination of uranium-bearing geology and extreme building pressure dynamics makes Fairbanks one of the higher-risk communities in the country on a per-home basis.

Anchorage and Southeast Alaska

Anchorage (Municipality of Anchorage) sits on glacial till and lake deposits that generally create lower radon conditions than interior Alaska’s bedrock geology, but meaningful radon risk still exists. Hillside communities in Anchorage that are closer to the Chugach Range bedrock show higher average levels than lower-elevation areas. Southeast Alaska communities — Juneau, Sitka, Ketchikan — overlie the Coast Mountains granite that extends from British Columbia, creating moderate to elevated radon potential in some areas. Eagle River and the Mat-Su Borough (Wasilla, Palmer) show elevated levels due to proximity to range geology.

Alaska Testing Resources

The Alaska Division of Environmental Health administers radon program resources. Alaska’s radon program provides educational materials and can direct homeowners to certified testing services. Due to Alaska’s geographic remoteness and small population in many areas, finding locally certified radon professionals can be more challenging than in the contiguous 48 states — the NRPP directory (nrpp.info) is the primary tool for identifying certified Alaska contractors. Mail-in laboratory radon test kits are the most practical testing option for many Alaskan communities.

Missouri has significant radon risk across much of the state, with an estimated 35–40% of Missouri homes testing above the EPA action level of 4.0 pCi/L. Missouri’s geology — including limestone and dolomite formations in the Ozark plateau, granite in the St. Francois Mountains, and glacial till in northern Missouri — creates varied but often elevated radon potential. The Missouri Department of Health and Senior Services administers the state radon program.

EPA Radon Zone Designation

Missouri counties range from Zone 1 in portions of northern and central Missouri to Zone 2 in the Ozark plateau and Zone 2-3 in the Mississippi lowlands of southeastern Missouri (“Bootheel”). The highest-radon areas include northern Missouri glaciated counties (Adair, Linn, Macon, Shelby, Knox, Lewis, Marion, Ralls, Pike, and Monroe counties), the St. Francois Mountains counties (St. Francois, Iron, Reynolds, Shannon), and the St. Louis metropolitan area (St. Louis County, St. Charles County).

Radon Contractor Requirements in Missouri

Missouri requires radon contractors to hold NRPP or NRSB national certification. Missouri’s radon program is administered through the Missouri Department of Health and Senior Services. Missouri does not have a separate state radon contractor licensing statute beyond national certification requirements. Verify contractor credentials at nrpp.info or nrsb.org before hiring.

Radon Disclosure in Missouri

Missouri’s Seller’s Disclosure Statement requires sellers to disclose known material defects. Missouri does not have a radon-specific disclosure statute, but known elevated radon conditions are material information that sellers should disclose under the general duty. Radon testing is recommended during the inspection period for all Missouri real estate transactions, particularly in northern and central Missouri and the St. Louis metro area.

Frequently Asked Questions

Is the St. Louis area high in radon?

St. Louis County and St. Charles County are in Zone 1 or Zone 2 with meaningful radon risk. Radon testing is recommended for all St. Louis metro homes. Older homes in the area with block foundations or basements should be prioritized.

Does Missouri require radon contractor certification?

NRPP or NRSB national certification is required. No separate Missouri licensing statute. Verify credentials at nrpp.info or nrsb.org before hiring.

What parts of Missouri have the highest radon?

Northern Missouri glaciated counties and the St. Francois Mountain counties of southeastern Missouri have the highest potential. The Kansas City and St. Louis metropolitan areas have significant radon risk. The Bootheel counties of extreme southeastern Missouri have generally lower levels.

Kansas City Metro Radon Risk

The Kansas City metropolitan area — which spans both Missouri and Kansas — has significant radon risk on the Missouri side. Jackson County (Kansas City proper) and the surrounding Missouri suburbs including Clay, Platte, Cass, and Ray counties show Zone 1 to Zone 2 radon levels. The Missouri side of the metro has glaciated geology in the north (Clay, Platte, Ray) transitioning to limestone and shale geology southward. Kansas City’s extensive older housing stock — particularly the bungalow and ranch-style homes with basements built throughout the post-WWII era — represents a significant untested population.

St. Louis Metro Radon

St. Louis County and St. Charles County on the Missouri side of the St. Louis metropolitan area are Zone 1 to Zone 2. The St. Francis Mountains geology (St. Francois County) — ancient Precambrian granite exposed at the surface — creates particularly high radon potential in Missouri’s Lead Belt region southeast of St. Louis. Jefferson County (south St. Louis suburbs) shows elevated readings. The city of St. Louis (independent city, Zone 2) has lower average levels than suburban St. Louis County but still warrants testing in older housing.

Missouri Testing Resources

The Missouri Department of Health and Senior Services (MDHSS) Radon Program provides certified contractor lists, county-level radon data from the Missouri Residential Radon Survey, and educational resources. Missouri participates in EPA’s SIRG program. The Missouri Geological Survey has published radon potential maps that provide more granular geological risk assessment than EPA’s county-level zone designations. Contact MDHSS for the current certified contractor list and test kit availability.

Connecticut has significant radon risk, particularly in its northern and western counties where the Reading Prong geological formation extends from Pennsylvania and New York into Connecticut. The Connecticut Department of Energy and Environmental Protection (DEEP) estimates that approximately 30% of Connecticut homes have radon levels above 4.0 pCi/L. Connecticut has enacted radon contractor certification requirements and maintains an active state radon program.

EPA Radon Zone Designation

Connecticut’s northern and western counties — Litchfield, Tolland, Windham, and Hartford counties — are Zone 1, reflecting the Reading Prong and Berkshire granitic geology extending from New York. New Haven and Middlesex counties are generally Zone 2. Fairfield County (southwestern Connecticut, bordering New York) shows elevated levels in its northern portions. New London County is Zone 2 to Zone 3.

Radon Contractor Requirements in Connecticut

Connecticut requires radon contractors to hold current NRPP or NRSB national certification. Connecticut’s radon program is administered through CT DEEP. Connecticut does not have a separate state radon licensing statute — national certification is the operative credential. Verify contractor credentials at nrpp.info or nrsb.org before hiring. CT DEEP maintains radon program information and resources on its website.

Radon Disclosure in Connecticut

Connecticut’s real estate disclosure law requires sellers to disclose known material defects through the Connecticut Residential Property Disclosure Report. The CT disclosure form includes environmental conditions — sellers with knowledge of elevated radon test results should disclose them. Connecticut real estate transactions routinely include radon testing contingencies, particularly in northern and western counties.

Frequently Asked Questions

What parts of Connecticut have the highest radon?

Northern and western Connecticut counties overlying Reading Prong and Berkshire granitic geology — Litchfield, Tolland, Windham, and northern Hartford counties — have the highest radon potential. The Hartford metro area shows moderate to high levels. Fairfield County (Stamford, Greenwich) is generally lower but northern Fairfield towns show elevated readings.

Does Connecticut require radon contractor certification?

NRPP or NRSB national certification is the operative requirement in Connecticut. No separate state licensing statute. Verify credentials at nrpp.info or nrsb.org before hiring.

Is radon testing important in Hartford or New Haven?

Yes. Hartford County is Zone 1 with significant radon risk. New Haven County is Zone 2. Radon testing is recommended throughout Connecticut and should be standard in real estate transactions in northern and western Connecticut especially.

Hartford Area Radon Specifics

Hartford County — Connecticut’s most populous county — is Zone 1 with significant radon risk across the greater Hartford area including West Hartford, Glastonbury, Simsbury, Avon, and Canton. The county’s Triassic basin sediments in the Connecticut River valley and the surrounding Proterozoic crystalline bedrock create a complex radon geology. Older Hartford-area homes with block or stone foundations are particularly vulnerable. The University of Connecticut campus in Storrs (Tolland County, Zone 1) is another Zone 1 community where student and faculty housing should be tested.

Reading Prong Extension into Connecticut

The Reading Prong geological formation extends into northwestern Connecticut through Litchfield County — the same uranium-rich granite that creates high radon in Montgomery County, Pennsylvania and Morris County, New Jersey reaches into Connecticut’s northwestern corner. Litchfield County communities including Torrington, Litchfield, and Winsted overlie this geology. Fairfield County’s northern towns — Ridgefield, New Canaan, Darien, and Greenwich (which borders New York’s Westchester County) — transition from lower Zone 2 coastline geology to higher-radon interior geology.

Connecticut Testing Resources

The Connecticut Department of Energy and Environmental Protection (CT DEEP) provides radon testing resources, certified contractor information, and county-level radon data. Connecticut participates in EPA’s SIRG program. CT DEEP’s radon program publishes indoor radon survey data from Connecticut residential testing. Contact CT DEEP for the current certified contractor list and test kit guidance. The NRPP directory (nrpp.info) provides real-time certification verification for Connecticut contractors.

West Virginia has significant radon risk statewide due to its Appalachian geology. The West Virginia Department of Health and Human Resources estimates that approximately 40% of West Virginia homes have radon levels above 4.0 pCi/L. West Virginia’s coal-bearing Appalachian formations, black shale, and sedimentary geology create elevated radon potential across much of the state. Virtually all of West Virginia’s counties have meaningful radon risk.

EPA Radon Zone Designation

Most West Virginia counties are Zone 1 or Zone 2. The northern and eastern counties overlying black shale and coal formations — including Monongalia, Marion, Harrison, Lewis, Upshur, Barbour, Tucker, Randolph, Pendleton, Hardy, Hampshire, Morgan, and Berkeley counties — show the highest average readings. The Eastern Panhandle counties (Berkeley, Jefferson, Morgan) are in the high-radon corridor extending from the Reading Prong formation in Pennsylvania and Maryland.

Radon Contractor Requirements in West Virginia

West Virginia requires radon contractors to hold NRPP or NRSB national certification. The West Virginia Department of Health and Human Resources administers radon program resources. West Virginia does not have a separate state radon licensing statute beyond national certification. Verify contractor credentials at nrpp.info or nrsb.org before hiring any radon professional.

Radon Disclosure in West Virginia

West Virginia’s Residential Property Disclosure Act requires sellers to disclose known material defects. West Virginia does not have a radon-specific disclosure statute, but known elevated radon conditions are material information that sellers should disclose under the general duty. The West Virginia Real Estate Commission provides guidance on radon disclosure.

Frequently Asked Questions

Is West Virginia a high-radon state?

Yes. Approximately 40% of West Virginia homes exceed 4.0 pCi/L. West Virginia’s Appalachian geology creates significant radon risk statewide, with the northern and eastern counties showing the highest average levels.

Is the Charleston or Morgantown area high in radon?

Monongalia County (Morgantown) is a Zone 1 county with elevated radon risk. Kanawha County (Charleston) is Zone 2. Both areas warrant radon testing, and testing is particularly important in Morgantown and northern West Virginia.

Does West Virginia require radon contractor certification?

NRPP or NRSB national certification is required. No separate West Virginia licensing statute. Verify credentials at nrpp.info or nrsb.org before hiring.

Eastern Panhandle High-Radon Corridor

West Virginia’s Eastern Panhandle counties — Berkeley, Jefferson, and Morgan — sit in the extension of the high-radon corridor that runs from Reading Prong Pennsylvania through Maryland into northern West Virginia. Berkeley County (Martinsburg area) and Jefferson County (Charles Town, Harpers Ferry) show elevated radon consistent with the Shenandoah Valley and Blue Ridge geology of this corridor. The rapid residential growth in the Eastern Panhandle — which serves as a bedroom community for the Washington D.C. metropolitan area — means many newer homes in this Zone 1 area should have been built with RRNC features, though this is not mandated statewide.

Morgantown and University Town Radon

Monongalia County (Morgantown, home of West Virginia University) is Zone 1 with elevated radon potential. The county’s Devonian and Mississippian shale formations underlie the mountainous terrain around Morgantown. Student rental housing, which often occupies older basement-heavy structures, can have radon levels that create significant cumulative exposure for student residents who spend multiple years in the area. WVU’s environmental health programs have been involved in radon awareness efforts for the Morgantown community.

West Virginia Testing Resources

The West Virginia Department of Health and Human Resources (WVDHHR) Radon Program provides testing resources, certified contractor information, and educational materials. WV participates in EPA’s SIRG program. Contact WVDHHR for the current certified contractor list and information on any available test kit assistance programs. The NRPP directory (nrpp.info) searchable by zip code provides real-time certification verification for all WV counties.

Kentucky has significant radon risk, particularly in its eastern Appalachian counties. The Kentucky Radon Program estimates that approximately 30% of Kentucky homes have radon levels above 4.0 pCi/L, with considerably higher percentages in Eastern Kentucky where Appalachian geology creates elevated radon potential. Kentucky’s limestone karst geology in the central Bluegrass region also creates radon pathways in some areas.

EPA Radon Zone Designation

Eastern Kentucky Appalachian counties are Zone 1 or Zone 2: Bell, Boyd, Breathitt, Carter, Clay, Elliott, Floyd, Greenup, Harlan, Jackson, Johnson, Knott, Knox, Lawrence, Lee, Leslie, Letcher, Lewis, Magoffin, Martin, McCreary, Menifee, Morgan, Owsley, Perry, Pike, Powell, Rowan, Wayne, and Whitley counties. The Bluegrass region and western Kentucky counties are generally Zone 2 to Zone 3.

Radon Contractor Requirements in Kentucky

Kentucky requires radon contractors to hold NRPP or NRSB national certification. Kentucky’s radon program is administered through the Kentucky Cabinet for Health and Family Services. Kentucky does not have a separate state radon licensing statute beyond national certification requirements. Verify contractor credentials at nrpp.info or nrsb.org before hiring.

Radon Disclosure in Kentucky

Kentucky’s real estate disclosure law requires sellers to disclose known material defects through the Kentucky Seller’s Disclosure of Property Condition. Known elevated radon results should be disclosed. Radon testing is particularly important in Eastern Kentucky transactions where the Appalachian geology creates high radon potential.

Frequently Asked Questions

What parts of Kentucky have the highest radon?

Eastern Kentucky’s Appalachian counties have the highest radon potential — particularly the coal-bearing counties of Pike, Floyd, Harlan, Letcher, Bell, and surrounding areas. The Lexington Bluegrass region shows moderate levels; Western Kentucky generally has lower but still meaningful radon risk.

Does Kentucky require radon contractor certification?

NRPP or NRSB national certification is required. No separate Kentucky licensing statute exists. Verify credentials at nrpp.info or nrsb.org before hiring.

Should I test for radon in Louisville or Lexington?

Yes. Jefferson County (Louisville) is Zone 2 with meaningful radon risk. Fayette County (Lexington) is in the Bluegrass Zone 2 area. Testing is recommended for all Kentucky homes, and should be standard in real estate transactions statewide.

Eastern Kentucky Coal Country Radon

Eastern Kentucky’s coal-bearing counties — Pike, Floyd, Harlan, Letcher, Perry, Knott, Leslie, and surrounding Appalachian counties — show some of the state’s highest average radon concentrations. The Pennsylvanian-age coal measures of the Cumberland Plateau and Pine Mountain region contain organic shale formations associated with elevated uranium concentrations. Homes in the mountain hollows of Eastern Kentucky, many with block or stone foundations built into hillsides, can have significant radon entry pathways from multiple directions.

Central Kentucky Bluegrass Radon

The Lexington Bluegrass region — Fayette County and surrounding counties including Madison, Clark, Bourbon, Scott, Woodford, and Jessamine — overlies Ordovician limestone and carbonate formations. These formations create karst topography (caves, sinkholes, and solution channels) that can serve as radon migration pathways. Fayette County shows Zone 2 radon levels with meaningful risk for Lexington homeowners. The Lexington area’s horse farm country, with older stone and block construction on larger rural properties, can have elevated radon particularly in older structures.

Kentucky Testing Resources

The Kentucky Cabinet for Health and Family Services (CHFS) Radon Program provides testing resources, certified contractor information, and county-level radon data. Kentucky participates in EPA’s SIRG program. The Kentucky Radon Program can provide guidance on test kit sources, certified contractor lists, and post-mitigation verification protocol. Contact CHFS directly or search nrpp.info for certified Kentucky radon contractors.

Utah has significant radon risk, with an estimated 40–45% of Utah homes testing above the EPA action level of 4.0 pCi/L. Utah’s geology — including uranium-bearing sandstone formations (Colorado Plateau), volcanic rock, granitic mountain ranges, and the Wasatch Front urban corridor geology — creates high radon potential across much of the state. Utah’s history as a major uranium mining state contributes to widespread radon-productive geological formations.

EPA Radon Zone Designation

Most Utah counties are Zone 1 or Zone 2. The Wasatch Front counties — Salt Lake, Utah, Davis, and Weber counties — show elevated radon levels and contain the vast majority of Utah’s population. Cache County (Logan area) and Summit County are also Zone 1. The Colorado Plateau counties of southeastern Utah — San Juan, Carbon, Emery, and Grand counties — overlie uranium-bearing sandstone and show high radon potential.

Radon Contractor Requirements in Utah

Utah does not have a state radon contractor licensing statute. Utah relies on NRPP and NRSB national certification as the operative credential for radon professionals. The Utah Department of Environmental Quality administers radon program resources. Search nrpp.info or nrsb.org for certified Utah radon professionals by location.

Radon in Utah’s Wasatch Front

The Wasatch Front urban corridor — where approximately 80% of Utah’s population lives — has significant radon risk. Salt Lake County homes, particularly older homes on the east bench with proximity to the Wasatch Range granitic geology, show elevated radon levels. The rapid pace of new residential construction along the Wasatch Front makes RRNC inclusion a significant public health opportunity. Utah DEQ strongly recommends testing for all Wasatch Front homes.

Frequently Asked Questions

Is the Salt Lake City area high in radon?

Yes. Salt Lake County and surrounding Wasatch Front counties — Utah, Davis, Weber — are Zone 1 or Zone 2 with elevated radon potential. Radon testing is recommended for all Wasatch Front homes, particularly those on the east bench near the mountain geology.

Does Utah require radon contractor licensing?

No. Utah has no state licensing statute. NRPP or NRSB national certification is the operative credential. Search nrpp.info for certified Utah contractors.

Why does Utah have high radon levels?

Utah sits on extensive uranium-bearing geological formations — the same Colorado Plateau sandstones that made Utah a major uranium mining state. Granitic mountain geology along the Wasatch Front also contributes. Combined with common slab-on-grade and basement construction in the Wasatch Front corridor, these create significant radon entry pathways.

Salt Lake and Utah County Radon Data

Salt Lake County and Utah County (Provo/Orem area) are the two most populous counties in Utah and show Zone 1 to Zone 2 radon levels. The east bench communities of Salt Lake City — Holladay, Millcreek, Cottonwood Heights — that sit closer to the Wasatch Range granite geology tend to show higher radon than lower valley communities. Utah County’s Provo-Orem corridor has similar patterns. Summit County (Park City) is Zone 1 with elevated radon from mountain granitic geology — a significant consideration given the area’s active real estate market and high-value homes.

Colorado Plateau Radon in Southeastern Utah

Southeastern Utah counties — San Juan, Carbon, Emery, Grand, and Garfield — sit on the Colorado Plateau’s uranium-bearing Chinle and Morrison Formation sandstones. The same geological formations that once supported extensive uranium mining in the Moab area (Grand County) produce ongoing radon in residential buildings. Carbon County (Price) and Emery County have historically elevated radon readings. Even in smaller southeastern Utah communities, radon testing is warranted.

Utah Testing Resources

The Utah Department of Environmental Quality (UDEQ) Division of Radiation Control administers the state radon program. UDEQ provides county-level radon data, certified contractor information, and educational materials. Utah participates in EPA’s SIRG program. The UDEQ radon program can provide specific guidance on testing methodology and interpretation for Utah’s unique geological context. Contact UDEQ or search nrpp.info by zip code for certified Utah radon professionals.

Idaho has significant radon risk, with an estimated 45% of Idaho homes testing above the EPA action level of 4.0 pCi/L. Idaho’s geology — including the Idaho Batholith (one of the largest granite formations in the U.S.), uranium-bearing rock in central and southern Idaho, and volcanic basalt on the Snake River Plain — creates varied but often high radon potential. The Idaho Department of Health and Welfare administers the state radon program.

EPA Radon Zone Designation

Most Idaho counties are Zone 1 or Zone 2. The highest-radon areas include northern Idaho counties overlying the Idaho Batholith granitic formations (Clearwater, Idaho, Latah, Lewis, and Nez Perce counties), central Idaho mining district counties (Custer, Lemhi, Blaine, and Camas counties), and southwestern Idaho counties including Ada (Boise metro) and Canyon counties. The Snake River Plain counties (Jefferson, Bingham, Bonneville) are generally Zone 2.

Radon Contractor Requirements in Idaho

Idaho does not have a state radon contractor licensing statute. Idaho relies on NRPP and NRSB national certification as the operative credentials for radon professionals. The Idaho Department of Health and Welfare maintains radon program resources but does not operate a separate state licensing program. Search the NRPP directory at nrpp.info or nrsb.org for certified Idaho radon professionals.

Radon Disclosure Requirements in Idaho

Idaho’s Seller Property Disclosure Act requires sellers to disclose known material defects. Idaho does not have a radon-specific disclosure statute, but known elevated radon conditions are material information that sellers should disclose under the general duty. The Idaho Real Estate Commission provides guidance on radon as a potential disclosure item.

Frequently Asked Questions

Why is Idaho a high-radon state?

Idaho sits on the Idaho Batholith — one of the nation’s largest granite formations — along with uranium-bearing rock in the central mining districts. These uranium-rich geological formations produce significant radon, particularly in northern and central Idaho.

Does Idaho require radon contractor licensing?

No. Idaho has no state radon contractor licensing statute. NRPP or NRSB national certification is the operative credential. Search nrpp.info for certified Idaho contractors.

Is the Boise area high in radon?

Ada County (Boise) and Canyon County are designated Zone 1 or Zone 2. Radon testing is recommended for all Treasure Valley homes. Northern Idaho counties overlying the Idaho Batholith generally have higher average levels than the Boise area.

Northern Idaho Mining Districts and Radon

Northern Idaho’s mining history — silver, lead, zinc, and gold mining in the Coeur d’Alene mining district — is associated with geology that also produces elevated radon. Shoshone County (the Silver Valley/Coeur d’Alene mining district) and Benewah, Kootenai, and Bonner counties in the Idaho Panhandle show significant radon potential. Clearwater County, Idaho County, and Lewis County in the north-central Idaho Clearwater region overlie the Idaho Batholith with high uranium content.

Boise Metro Radon Specifics

The Treasure Valley (Ada and Canyon counties) has Zone 1 to Zone 2 radon designation. The Boise Front — the foothills rising from the valley floor toward the Boise Mountains — shows higher average radon levels than the lower valley floor. Homes built on or near the foothills, or in older established Boise neighborhoods closer to the mountain geology, tend to test higher. Canyon County (Nampa, Caldwell) shows similar patterns to Ada County. Eagle, Meridian, and Star — rapidly growing Treasure Valley communities — warrant testing regardless of new construction date.

Idaho Testing Resources

The Idaho Department of Health and Welfare (IDHW) Bureau of Community and Environmental Health administers radon program resources. IDHW participates in EPA’s SIRG program. Idaho does not have a comprehensive state testing database as large as some states, but IDHW provides county-level risk information and certified contractor referrals. The NRPP directory (nrpp.info) searchable by zip code is the most reliable way to find certified Idaho radon professionals.

Tennessee has significant radon risk, particularly in its eastern Appalachian counties. The Tennessee Department of Environment and Conservation estimates that approximately 30% of Tennessee homes have radon levels above 4.0 pCi/L statewide, with considerably higher percentages in Eastern Tennessee where the Appalachian geology creates elevated radon potential. Tennessee has enacted radon contractor licensing requirements.

EPA Radon Zone Designation

Eastern Tennessee counties overlying the Appalachian ridge and valley geology are Zone 1: Anderson, Blount, Bradley, Campbell, Claiborne, Cumberland, Grainger, Greene, Hamilton, Hawkins, Jefferson, Knox, Loudon, McMinn, Meigs, Monroe, Morgan, Polk, Rhea, Roane, Scott, Sevier, Sullivan, Union, and Washington counties. Middle and West Tennessee counties are generally Zone 2 to Zone 3.

Radon Contractor Licensing in Tennessee

Tennessee requires radon contractors to hold current NRPP or NRSB national certification, and Tennessee has additional state registration requirements for radon professionals. The Tennessee Department of Environment and Conservation administers radon program resources. Tennessee maintains a registry of radon measurement and mitigation service providers. Verify contractor credentials through TDEC and through the national NRPP/NRSB directories before hiring.

Radon Disclosure Requirements in Tennessee

Tennessee’s Residential Property Condition Disclosure Act requires sellers to disclose known material defects. The Tennessee disclosure form includes environmental conditions — sellers with knowledge of elevated radon test results should disclose them. Tennessee does not have a radon-specific disclosure statute, but the general material defect obligation applies. Radon testing is particularly important in Eastern Tennessee transactions.

Frequently Asked Questions

What parts of Tennessee have the highest radon?

Eastern Tennessee’s Appalachian counties — including Knox (Knoxville), Hamilton (Chattanooga), Bradley, Anderson, and surrounding ridge-and-valley counties — have the state’s highest radon potential. Middle and West Tennessee counties generally have lower levels.

Does Tennessee require radon contractor certification?

Tennessee requires NRPP or NRSB national certification and has additional state registration requirements. Verify credentials through TDEC and nrpp.info before hiring.

Should I test for radon in Knoxville or Chattanooga?

Yes. Both Knoxville (Knox County) and Chattanooga (Hamilton County) are in Zone 1 Appalachian counties. Radon testing is strongly recommended for all homes in Eastern Tennessee, and should be standard in real estate transactions in these areas.

Knoxville and Chattanooga Area Radon

Knox County (Knoxville) and Hamilton County (Chattanooga) are Zone 1 Appalachian counties where radon is a significant public health concern. The Knoxville metropolitan area — which includes Knox, Anderson, Blount, Loudon, Sevier, Union, and Grainger counties — sits within the Appalachian Valley and Ridge province where limestone, dolostone, and shale formations create both radon-producing geology and preferential pathways for radon migration into homes. The Tennessee Department of Environment and Conservation (TDEC) has documented elevated radon testing results throughout the Knoxville metro.

Tennessee Testing Resources

The Tennessee Department of Environment and Conservation Radon Program provides resources including information on certified contractors, radon testing guidance, and educational materials for homeowners. TDEC participates in EPA’s SIRG program. Tennessee also participates in the Appalachian Regional Radon Outreach Initiative, which coordinates radon awareness across Appalachian states. Contact TDEC directly for the current certified contractor list and any test kit assistance programs.

Radon in Nashville and Memphis

Davidson County (Nashville) is Zone 2 with moderate radon potential. The Nashville Basin’s limestone geology creates some radon risk, though lower than the Appalachian counties to the east. Shelby County (Memphis) is Zone 2 to Zone 3. Middle and West Tennessee homeowners should still test — the 30% statewide prevalence rate means elevated radon is found throughout Tennessee, not just in the eastern Appalachian counties.