What is Radon: The Invisible Radioactive Gas in Your Home

Why radon is the problem:

• •Radon is the only gas in this decay chain
• •As a gas, it can move freely through soil and enter buildings
• •Once inhaled, radon decay products (especially polonium) damage lung tissue
• •The decay process releases alpha particles that cause cellular damage

Radon is everywhere:

• •Uranium exists naturally in all soil and rock formations
• •Every country has radon
• •Some areas have higher concentrations than others
• •But any home can have a radon problem regardless of location

High uranium soil:

• •Granite formations
• •Phosphate-rich soil
• •Certain shale and sedimentary rocks
• •Volcanic areas
• •Former mining regions

Soil permeability:

• •Sandy, gravelly soil allows easier radon movement
• •Clay soil restricts radon movement but doesn't eliminate it
• •Fractured bedrock provides pathways

Geographic variation:

• •Some regions have higher average levels
• •But specific home's level depends on many factors
• •Only testing tells you your home's level
• •Neighbor's results don't predict yours

Global distribution:

• •Europe: Significant areas with elevated radon
• •North America: Found throughout US and Canada
• •Asia: Present in Japan, China, India, and elsewhere
• •Every continent has radon

Why indoor pressure is lower:

• •Warm air rises and exits through upper levels
• •Creates negative pressure at lower levels
• •Soil pressure is typically higher
• •Pressure difference acts like a vacuum

Factors increasing the pressure difference:

• •Heating systems (especially in winter)
• •Exhaust fans (bathrooms, kitchens, dryers)
• •Fireplaces and wood stoves
• •HVAC systems
• •Temperature differences (warm inside, cold outside)
• •Wind conditions

Foundation openings:

• • - Concrete slabs develop cracks over time
• • - Even hairline cracks allow radon entry
• • - Normal settling causes cracks

2. Construction joints

• • - Where floor meets wall
• • - Where walls meet each other
• • - Intentional gaps in construction

3. Cracks in walls

• • - Foundation wall cracks
• • - Below-grade wall cracks
• • - Mortar joints in block walls

Penetrations:

• • - Plumbing penetrations
• • - Electrical conduits
• • - HVAC ducts
• • - Any pipe passing through foundation

5. Gaps in suspended floors

• • - Spaces between floor boards
• • - Openings around floor penetrations

6. Cavities inside walls

• • - Hollow block foundation walls
• • - Space between double walls
• • - Wall cavities act as radon channels

Other entry routes:

• • - Uncovered or poorly sealed sumps
• • - Direct path from soil to indoor air

8. Floor drains

• • - Dried-out drain traps
• • - Direct connection to soil

9. Crawlspace vents

• • - In homes with crawlspaces
• • - Radon accumulates in crawlspace, then enters home

Well water:

• •Radon dissolves in groundwater
• •Released when water is used for:

Contribution from water:

• •Typically accounts for 1-2% of total radon in air
• •Can be higher in homes with very high water radon levels
• •More significant with private wells than public water

When water radon is a concern:

• •Private well water (not treated)
• •Public water systems using groundwater
• •Surface water (rivers, lakes) rarely has radon
• •Testing both air and water recommended if concerned

Building materials (rare):

• •Certain granite countertops
• •Some concrete products
• •Specific types of brick

Why materials rarely cause problems:

• •Amount of uranium in materials usually very low
• •Radon from materials is minor compared to soil gas
• •Would need extensive use of radioactive materials
• •Not a significant source in most homes

1. You breathe radon gas

• • - Radon enters lungs with normal breathing
• • - No immediate symptoms or sensation

2. Radon decays in your lungs

• • - Half-life of 3.8 days means some radon decays while in lungs
• • - Decay products (especially polonium) are solid particles

3. Decay products get trapped

• • - Polonium particles attach to lung tissue
• • - Cannot be exhaled like the gas
• • - Remain in lungs for extended periods

4. Alpha particles damage cells

• • - Polonium continues to decay
• • - Releases alpha particles (high energy)
• • - Alpha particles damage DNA in lung cells

5. Damaged cells may become cancerous

• • - Over months and years, damage accumulates
• • - Cellular DNA repair may fail
• • - Cancer may develop

The invisible danger:

• •No immediate symptoms
• •No short-term health effects
• •Damage occurs gradually
• •Cancer may develop years or decades later
• •By the time symptoms appear, it's too late for prevention

Global impact:

• •Radon causes tens of thousands of lung cancer deaths annually worldwide
• •In United States alone: approximately 21,000 deaths per year
• •Second only to smoking as a cause of lung cancer
• •Responsible for about 10-15% of all lung cancer cases

For smokers:

• •Risk multiplies (synergistic effect)
• •Most radon-related lung cancers occur in smokers
• •Combination is especially deadly

For non-smokers:

• •Still significant risk
• •Leading cause of lung cancer in non-smokers
• •Risk increases with radon level and duration of exposure

Comparison to other risks:

• •For smokers: 250x the risk of drowning
• •For non-smokers: 35x the risk of drowning

The preventable tragedy:

• •Radon-related lung cancer is entirely preventable
• •Testing and mitigation eliminate most of the risk
• •Yet millions of homes remain untested

Highest risk groups:

• •People who smoke or have smoked
• •Long-term residents of high-radon homes
• •People who spend significant time in basements or ground-floor spaces
• •Young people (more years of exposure ahead)

Factors affecting individual risk:

• • - Higher levels = higher risk
• • - Risk approximately linear with dose

2. Time spent at home

• • - More time in high-radon environment = more exposure
• • - Work-from-home increases exposure

3. Smoking status

• • - Smokers face 10-25x higher risk from radon
• • - Former smokers still have elevated risk
• • - Never-smokers face significant but lower risk

4. Age

• • - Younger people have more years of potential exposure
• • - More time for cancer to develop
• • - But older people also benefit from risk reduction

Populations with potentially higher exposure:

• •Basement apartment residents
• •Home-based workers
• •Retired individuals (more time at home)
• •Night-shift workers (sleep during day at home)

Why homes are the primary concern:

• •Where people spend most time (50-70% of day)
• •Where exposure is longest-term
• •Where exposure is most controllable

All home types affected:

• •Single-family houses
• •Apartments and condominiums
• •Townhouses
• •Mobile homes (if on foundation)
• •All foundation types (basement, slab, crawlspace)

Testing responsibility:

• •Homeowners should test
• •Renters should request testing or test themselves
• •Each unit in multi-unit buildings needs individual testing

Special concern:

• •Children may be more vulnerable to radiation
• •Long hours spent in buildings
• •Large numbers of people exposed

Testing recommendations:

• •All schools should test
• •Daycare facilities should test
• •Ground-floor and basement classrooms priority
• •Regular retesting recommended

Who to contact:

• •School administration
• •Local education department
• •Regional radon program

Employee protection:

• •Workers spend 8+ hours per day in workplace
• •Exposure can equal or exceed home exposure
• •Employer responsibility to provide safe environment

High-priority workplaces:

• •Basement offices
• •Ground-floor spaces
• •Older buildings
• •Buildings in high-radon areas

Testing and mitigation:

• •Employers should test workplace
• •Workers can request testing
• •Occupational health regulations may apply