Radon is an invisible, odorless radioactive gas that can enter buildings from the soil beneath them. Because you cannot see, smell or taste radon, testing is the only way to know whether elevated levels are present.
The U.S. Environmental Protection Agency recommends that homes be fixed when radon levels are 4 picocuries per liter (pCi/L) or higher and that home- owners consider taking action at levels between 2 and 4 pCi/L. EPA also states that there is no known safe level of radon exposure.
Yet there is currently no federal law— and no state law — that requires every privately owned home in America to be periodically tested and mitigated when elevated radon is found.
The Building Blocks Already Exist
Such a policy would not be entirely new. Across the United States, states and local governments have already enacted pieces of what could eventually become a comprehensive residential radon- prevention model.
Maine provides one of the strongest examples. State law requires radon
testing in many residential rental properties. Landlords must disclose results to tenants, and when radon is found at 4 pCi/L or higher, covered properties must be mitigated within the timeframe established by state law.
Rhode Island took another major step in 2026. Legislation enacted June 18, 2026, establishes new radon requirements
for covered residential real - estate transactions beginning June 1, 2027. Generally, a qualifying property must
have a radon test performed no earlier than one year before closing.
When unsafe radon levels are found, mitigation is required, subject to statutory provisions and exceptions.
If mitigation cannot be completed
before closing, funds for the estimated mitigation cost may be placed in escrow.
Colorado has also strengthened residential protections. The state requires specified radon disclosures in residential sales and rental transactions. Colorado law also provides remedies for tenants when elevated radon is identified and a landlord fails to make a reasonable effort to mitigate within the period established by law.
Continued on next page ...
Schools and Child-Care Facilities Provide Additional Models
States have also demonstrated that mandatory testing can protect children where they spend significant amounts of time.
Iowa's Gail Orcutt School Radon Safety Act requires public-school districts to establish radon testing plans, test school attendance centers by July 1, 2027, and retest at least every five years. When testing identifies levels above 4 pCi/L, districts must involve a credentialed mitigation specialist in developing a mitigation plan. New school construction must incorporate radon-resistant construction techniques.
Illinois requires licensed early-care and education centers, homes and group homes to undergo radon testing at least once every three years.
Florida requires radon testing in certain schools, day-care centers and specified 24-hour care facilities in designated areas of the state. Florida's requirements illustrate an important distinction, however: mandatory testing does not automatically mean that the radon testing law itself mandates mitigation. Corrective requirements can depend upon the type of facility and the agency regulating it.
A 2021 Environmental Law Institute review identified 10 states with laws requiring radon testing and/or mitigation in certain licensed child-care settings: Colorado, Connecticut, Delaware, Florida, Illinois, Iowa, Michigan, New Jersey, New York and Rhode Island. Because radon laws continue to evolve, that number should not be treated as a definitive count for 2026.
Some Local Governments Have Gone Even Further
Local governments provide additional examples of residential radon policy.
Iowa City has adopted requirements addressing radon testing and mitigation in single-family and duplex rental properties. Montgomery County, Maryland, has also required landlords of certain rental properties to test for radon, disclose results and mitigate when levels reach or exceed 4 pCi/L.
These policies demonstrate an important point:
Mandatory radon testing and mitigation are not merely theoretical ideas. Pieces of this public-health model are already operating in American communities.
The larger question is what would happen if those pieces were brought together.
What If We Expanded These Protections to Every Home?
Imagine a comprehensive state law requiring every residential property to have a documented radon test at specified intervals and at important trigger points, such as the sale or rental of a home, major renovation, new construction or transfer of ownership.
When testing confirms radon at or above 4 pCi/L, mitigation would be required within a reasonable period.
The potential impact could be enormous.
Millions more homes would be tested. Elevated homes that might otherwise remain unidentified for decades could be discovered. Families could learn about dangerous radon exposure before someone in the household develops lung cancer.
States could also collect anonymized testing and mitigation data, helping public-health agencies identify communities with high concentrations of elevated homes and direct education, testing resources and mitigation assistance where they are needed most.
A Mandate Must Include Financial Assistance
Mandatory mitigation, however, cannot be separated from affordability.
A law requiring a family to spend money it does not have to correct an environmental health hazard could create another form of health inequity.
A comprehensive Radon-Safe Homes Act should therefore pair mandatory testing and mitigation with financial assistance for qualifying low- and moderate-income households.
Federal and state grants, tax credits, housing programs, community-development funds, health-system investments and nonprofit partnerships could help pay for testing and mitigation.
No family should be forced to choose between continuing to live with a known carcinogen and paying a mitigation bill it cannot afford.
Make Radon-Resistant Homes the Standard
Universal radon legislation could also address the homes America has not yet built.
Building codes could require radon-resistant new construction in areas where appropriate, making radon prevention part of the home from the beginning rather than waiting until elevated levels are discovered years later.
Over time, radon protection could become as routine as other residential health and safety measures.
From Radon Awareness to Radon Prevention
For decades, America's radon strategy has depended heavily upon educating homeowners and encouraging voluntary testing. Education remains essential, but voluntary action alone cannot ensure that every family lives in a radon-safe environment.
Existing laws in Maine, Rhode Island, Colorado, Iowa, Illinois, Florida and local jurisdictions demonstrate that government can establish stronger radon protections.
The United States does not have to invent the concept from scratch.
The pieces already exist.
The next step would be bringing those pieces together into a comprehensive policy that protects people wherever they live.
If every state required residential radon testing, required elevated homes to be fixed and provided financial assistance to families who could not afford mitigation, America could fundamentally change its approach to radon-induced lung cancer.
Instead of discovering the exposure after a cancer diagnosis, we could identify and reduce the exposure years earlier.
Test every home. Identify every elevated home. Help families fix it. Prevent the exposure before it becomes cancer.
Imagine if every
state passed legislation requiring homes to be tested for radon gas—and requiring elevated levels to be reduced. Instead of waiting for people to develop lung cancer before asking about environmental exposures, America could begin preventing one of those exposures at
its source.
What If Every Home in America Had to Be Radon-Safe?
Oped August 2026
Imagine if every state passed legislation requiring homes to be tested for radon gas—and requiring elevated levels to be reduced. Instead of waiting for people to develop lung cancer before asking about environmental exposures, America could begin preventing one of those exposures at its source.
Radon is an invisible, odorless radioactive gas that can enter buildings from the soil beneath them. Because you cannot see, smell or taste radon, testing is the only way to know whether elevated levels
are present.
The U.S. Environmental Protection Agency recommends that homes be fixed when radon levels are 4 picocuries per liter (pCi/L) or higher and that homeowners consider taking action at levels between
2 and 4 pCi/L. EPA also states that there is no known safe level of radon exposure.
Yet there is currently no federal law—and no state law—that requires every privately owned home in America to be periodically tested and mitigated when elevated radon is found.
The Building Blocks Already Exist
Such a policy would not be entirely new. Across the United States, states and local governments have already enacted pieces of what could eventually become a comprehensive residential radon- prevention model.
Maine provides one of the strongest examples. State law requires radon
testing in many residential rental properties. Landlords must disclose results to tenants, and when radon is found at 4 pCi/L or higher, covered properties must be mitigated within the timeframe established by state law.
Rhode Island took another major step in 2026. Legislation enacted June 18, 2026, establishes new radon requirements
for covered residential real - estate transactions beginning June 1, 2027. Generally, a qualifying property must
have a radon test performed no earlier than one year before closing. When
unsafe radon levels are found, mitigation is required, subject to statutory provisions and exceptions. If mitigation cannot be completed before closing, funds for the estimated mitigation cost may be placed in escrow.
Colorado has also strengthened residential protections. The state requires specified radon disclosures in residential sales and rental transactions. Colorado law also provides remedies for tenants when elevated radon is identified and a landlord fails to make a reasonable effort to mitigate within the period established by law.
Schools and Child-Care Facilities Provide Additional Models
States have also demonstrated that mandatory testing can protect children where they spend significant amounts of time.
Iowa's Gail Orcutt School Radon Safety Act requires public-school districts to establish radon testing plans, test school attendance centers by July 1, 2027, and retest at least every five years. When testing identifies levels above 4 pCi/L, districts must involve a credentialed mitigation specialist in developing a mitigation plan. New school construction must incorporate radon-resistant construction techniques.
Illinois requires licensed early-care and education centers, homes and group homes to undergo radon testing at least once every three years.
Florida requires radon testing in certain schools, day-care centers and specified 24-hour care facilities in designated areas of the state. Florida's requirements illustrate an important distinction, however: mandatory testing does not automatically mean that the radon testing law itself mandates mitigation. Corrective requirements can depend upon the type of facility and the agency regulating it.
A 2021 Environmental Law Institute review identified 10 states with laws requiring radon testing and/or mitigation in certain licensed child-care settings: Colorado, Connecticut, Delaware, Florida, Illinois, Iowa, Michigan, New Jersey, New York and Rhode Island. Because radon laws continue to evolve, that number should not be treated as a definitive count for 2026.
Some Local Governments Have Gone Even Further
Local governments provide additional examples of residential radon policy.
Iowa City has adopted requirements addressing radon testing and mitigation in single-family and duplex rental properties. Montgomery County, Maryland, has also required landlords of certain rental properties to test for radon, disclose results and mitigate when levels reach or exceed 4 pCi/L.
These policies demonstrate an important point:
Mandatory radon testing and mitigation are not merely theoretical ideas. Pieces of this public-health model are already operating in American communities.
The larger question is what would happen if those pieces were brought together.
What If We Expanded These Protections to Every Home?
Imagine a comprehensive state law requiring every residential property to have a documented radon test at specified intervals and at important trigger points, such as the sale or rental of a home, major renovation, new construction or transfer of ownership.
When testing confirms radon at or above 4 pCi/L, mitigation would be required within a reasonable period.
The potential impact could be enormous.
Millions more homes would be tested. Elevated homes that might otherwise remain unidentified for decades could be discovered. Families could learn about dangerous radon exposure before someone in the household develops lung cancer.
States could also collect anonymized testing and mitigation data, helping public-health agencies identify communities with high concentrations of elevated homes and direct education, testing resources and mitigation assistance where they are needed most.
A Mandate Must Include Financial Assistance
Mandatory mitigation, however, cannot be separated from affordability.
A law requiring a family to spend money it does not have to correct an environmental health hazard could create another form of health inequity.
A comprehensive Radon-Safe Homes Act should therefore pair mandatory testing and mitigation with financial assistance for qualifying low- and moderate-income households.
Federal and state grants, tax credits, housing programs, community-development funds, health-system investments and nonprofit partnerships could help pay for testing and mitigation.
No family should be forced to choose between continuing to live with a known carcinogen and paying a mitigation bill it cannot afford.
Make Radon-Resistant Homes the Standard
Universal radon legislation could also address the homes America has not yet built.
Building codes could require radon-resistant new construction in areas where appropriate, making radon prevention part of the home from the beginning rather than waiting until elevated levels are discovered years later.
Over time, radon protection could become as routine as other residential health and safety measures.
From Radon Awareness to Radon Prevention
For decades, America's radon strategy has depended heavily upon educating homeowners and encouraging voluntary testing. Education remains essential, but voluntary action alone cannot ensure that every family lives in a radon-safe environment.
Existing laws in Maine, Rhode Island, Colorado, Iowa, Illinois, Florida and local jurisdictions demonstrate that government can establish stronger radon protections.
The United States does not have to invent the concept from scratch.
The pieces already exist.
The next step would be bringing those pieces together into a comprehensive policy that protects people wherever they live.
If every state required residential radon testing, required elevated homes to be fixed and provided financial assistance to families who could not afford mitigation, America could fundamentally change its approach to radon-induced lung cancer.
Instead of discovering the exposure after a cancer diagnosis, we could identify and reduce the exposure years earlier.
Test every home. Identify every elevated home. Help families fix it. Prevent the exposure before it becomes cancer.
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