This is a radon information power point. Learn more about radon, testing methods, and mitigation. Radon testing should be an important part of any real estate transaction.
1. Inspections You Can Trust
Radon Environmental Issues
for Real Estate Professionals
2. • No. 1 cause of lung cancer
among nonsmokers
• Second leading cause of lung
cancer in the United States and
Canada (next to cigarette smoke)
• A smoker who is also exposed to
radon has a much higher risk of
developing lung cancer
• Claims 21,000 lives each year
What Is Radon?
3. • A radioactive gas
• Comes from the natural decay of
uranium found in nearly all soils
• Typically moves up through the
soil to the air of your home through
cracks and other holes in
the foundation
About Radon
4. • Any home may have a
radon problem
• Radon can be found in any
type of home, including new
homes, old homes, well-
sealed and drafty homes
• Radon can be found in
homes with basements,
crawlspaces or slabs
Where Radon Comes From
5. • Cracks in solid floors
• Construction joints
• Cracks in walls
• Gaps in suspended floors
• Gaps around service
pipes
• Cavities inside walls
• The water supply
Where Radon Comes From
6. • Test for radon during a real
estate transaction
• Fix the home if the radon level
is 4 picoCuries per liter (pCi/L)
or higher
• Radon levels less than 4 pCi/L
still pose a risk, and in many
cases may be reduced
Radon
Source: Zone and legend map provided by EPA Web site
7. • Even if built to be radon-resistant,
every new home should be tested
for radon as soon as possible
after occupancy.
• If you have a test result of 4 pCi/L
or more, a radon fan can easily be
added to a passive system to
make it an active system and
further reduce radon levels.
About Radon
8. Ensure that the test is approved
o EPA does not approve radon test devices
o The National Environmental Health Association
(NEHA) approves radon test devices
o The National Radon Safety Board (NRSB) approves
radon test devices
Radon Testing
9. • Passive Devices
o Charcoal canisters
o Alpha-track detectors
o Charcoal liquid scintillation
• Available in hardware stores (plumbing department)
• Generally requires at least 48 hours to complete
Testing Options: Passive Devices
10. • E-perm results can be
calculated immediately
upon retrieval of canister
following the test period
• E-perm uses electret
ion chamber (EIC)
technology
Radon Canisters
11. • Active devices are the following:
o Continuous radon monitors (CRMs)
o Continuous working-level monitors
• Require operation by trained testers
• Provide a continuous report of radon levels present
• Reveal unusual/abnormal swings in the levels during the
test period
• Designed to deter and detect test interference/tampering
• More costly than a passive device
• Ensure a more reliable result
Testing Options: Active Devices
12. • Instant results are
available at the push
of a button following
the test period
Continuous Monitors
13. A method using an active or inactive system to reduce
radon levels in a home
Radon Mitigation
14. • Gas-permeable layer (stone)
• Vapor barrier (prevents soil
gas entry)
• Sealed joints
• 3- or 4-inch PVC pipe
• Junction box for future fan
in attic
Passive Mitigation
15. Active systems use a fan to direct the radon out of
the home:
• Sub-slab suction
• Drain tile suction
• Sub-membrane suction
• Combination
Active Mitigation
16. • Sometimes there is a lack of
drain tile for sub-slab homes to
tap into.
• In most modern construction,
there is a drain tile under the
slab that, when tapped into, can
achieve good communication.
• The pipe is run up through the
attic and through the roof or
side wall (interior), or on the
exterior of the home.
Sub-slab Mitigation
18. • Installing a pipe through the slab to get to the drain tile
can create good communication under the slab
• Sump pits need to be sealed to prevent the home’s
conditioned air from being sucked out of the home
• Sump pits are also a good suction point to reach the
drain tile
Drain Tile Mitigation
21. • Homes with crawl spaces with high radon levels require
a 6-mm vapor barrier to be installed on the floor and
sealed to the perimeter wall
• All penetrations must be sealed through vapor barrier
• A pipe is installed under the membrane and is the
suction point
Sub-membrane Mitigation
22. • Suction points from basement and crawl spaces and/or
slabs can be joined together to run to the outside
Combination
23. • The pipe should terminate
above the roof edge and not
halfway up the side of the
home to prevent concentrated
radon levels from
re-entrainment/re-entry back
into the home
• SHOULD NOT use
gutter/downspout as
exhaust pipe
Pipe Termination
24. • SHOULD be above the eave of the roof
• SHOULD be 10 feet or more above ground level
• SHOULD be 10 feet or more from any window, door or
other opening into conditioned spaces of the structure
that are less than 2 feet below the exhaust point
• SHOULD be 10 feet or more from any opening into an
adjacent building
Pipe Termination
26. • SHOULD be located on the outside of the home
• SHOULD be located in an attic
• SHOULD NOT be located in a basement or crawlspace
• Electrical disconnect SHOULD be located where fan is
and not in another room
Fan Location
29. • Floor drains need sealing
o Using a check valve, these floor drains can still
be used
• Fire collars are needed when a penetration occurs on
the firewall, typically between the garage and the
basement or crawl space
Special Items
Radon in water is found in only certain areas of the country (more commonly on the East Coast).
PicoCuries are the measure of radiation in a fluid.
EIC technology is a passive integrating ionization monitor consisting of a stable electret mounted inside a small chamber made of electrically conducting plastic. Radon gas passively diffuses into the chamber through filtered inlets, and the alpha particles emitted by the decay process ionize air molecules. Ions produced inside the chamber are collected onto the electret, causing a reduction of its surface charge.
Gutter vent leaked, causing spauling to brick work. All bricks had to be repaired.
Red rings are fire collars that expand when heated to close off opening if pipe melts in fire. Other (rubber check valves).
