Homes - Indoor Air Quality
is Radon? Radon is a naturally occurring, invisible,
odorless gas that comes from deposits of uranium in soil,
rock, and water. It is harmlessly dispersed in outdoor air,
but when trapped in buildings, can be harmful, especially
at elevated levels. Radon is a radioactive decay product
of radium, which is itself a decay product of uranium. Uranium
and radium are both common elements in soil.
is Radon Found? The primary source of high levels of
radon in homes is the surrounding soil. Radon has been found
in elevated levels in homes in every state, and the U.S.
Environmental Protection Agency estimates that as many as
one in 15 homes across the U.S. have elevated radon levels.
Does Radon Get Into My House? Warm air rises. When this
happens in your home, it creates a vacuum in the lower areas
of the house. Nature hates a vacuum, so something must rush
in to fill it. In the case of your home, air seeps in from
the soil around and under the house, and some air is sucked
in through openings (cracks, doors, windows) on the lower
levels. Radon gas enters the same way air and other soil
gases enter the home; through cracks in the foundation floor
or walls, hollow-block walls, and openings around floor
drains, pipes and sump pumps.
are the Health Effects of Radon? Exposure to radon is
the second leading cause of lung cancer in the U.S. Radon
can be inhaled into the lungs, where it undergoes radioactive
decay. As it decays, radon releases tiny bursts of energy
called alpha particles, which can harm sensitive lung tissue
by damaging the DNA. This damaged DNA can lead to lung cancer.
is Radon Measured? Radon is measured in picocuries per
liter of air (pCi/L), a measurement of radioactivity. The
U.S. EPA and the Centers for Disease Control and Prevention
recommend that homes with radon levels 4 pCi/L, or greater,
do I Find Out if My House has Elevated Levels of Radon?
Radon test kits that meet EPA guidelines can be obtained
from a radon testing company or laboratory. Get a listing
from your state radon office or local health department.
They are available at local hardware stores and home improvement
stores. Many are priced under $25.00. Testing your home
for radon is as simple as opening a package, placing a radon
detector in a designated area, and, after the prescribed
number of days, sealing the detector back in the package
and mailing it to a lab. Information on testing your home
for radon and how to get a test kit is also available by
cost of making repairs to reduce radon depends on how your
home was built and other factors. Most homes can be fixed
for about the same cost as other common home repairs, like
painting or having a new hot water heater installed. The
average cost for a contractor to lower radon levels in a
home is about $1,200, although this can range from $500
to about $2,500.
Can I Fix My House if it has Elevated Levels of Radon?
A variety of methods can be used to reduce radon in homes.
Sealing cracks and other openings in the foundation is a
basic part of most approaches to radon reduction. EPA does
not recommend the use of sealing and caulking alone to reduce
radon because, by itself, sealing has not been shown to
lower radon levels significantly or consistently. In most
cases, systems with pipes and fans are used to reduce radon.
Such systems are called Asub-slab depressurization@. These
systems prevent radon gas from entering the home from below
the concrete floor and the foundation. Similar systems can
also be installed in homes with crawl spaces. Radon reduction
contractors may use other methods that may also work in
your home, depending on its design and other factors. Look
in the Yellow Pages or call your state radon office to locate
radon mitigators in your area.
Some Common Radon Myths
don't have a basement, so I probably don't have a radon
problem." Radon can seep in from soil anywhere
around or under a home, regardless of whether your home
has a basement, a crawl space, or is built slab-on-grade.
The U.S. Environmental Protection Agency and the Surgeon
General recommend radon testing for all types of homes.
In multi-level homes testing should be done on a level below
the third floor.
don't live in an area designated as a high radon zone, so
my home won't have a problem." The U.S. EPA and
the U.S. Geologic Survey conducted surveys of radon potential
across the United States. They broke the country down into
three zones according to their potential for high indoor
radon levels, with Zone 1 having the highest radon potential.
It is true that homes in Zones 1 and 2 have a statistically
higher chance of having elevated levels of radon. However,
the fact is that elevated levels of radon have been found
in homes in all fifty states. The radon level in your home
depends on the geology under and near your home. The only
way to know for sure, and to protect your family from radon,
is to test your home.
of my neighbors have tested their homes for radon and they
don't have high levels, so I probably don't either."
Radon levels can vary considerably from house to house,
even on the same street. It is nearly impossible to predict
the exact nature of geologic soil deposits and the extent
to which soil gasses will seep into and be retained by a
specific house. The only way to know whether radon exists
in elevated levels in your home, and to protect your family
from radon, is to test.
doesn't seem to be much proof that radon is a serious health
problem." The science on radon has been formidable
over the years, but never before have we had such overwhelming
scientific consensus that exposure to elevated levels of
radon causes lung cancer in humans. In February of 1998,
the National Academy of Sciences (NAS) presented the findings
of their Biological Effects of Ionizing Radiation (BEIR)
VI Report: "The Health Effects of Exposure to Indoor
Radon." This new report by the NAS is the most definitive
accumulation of scientific data on indoor radon. The report
confirms that radon is the second leading cause of lung
cancer in the U.S. and that it is a serious public health
problem. The study fully supports U.S. EPA estimates stating
that radon causes between 15,000 and 22,000 lung cancer
deaths per year.
don't have time to test for radon!" Testing is
as simple as opening a package, placing a radon detector
in your home in a designated area, and, after the prescribed
number of days (typically two days), sealing the detector
back in the package and mailing it to a lab. The whole process
only takes a few minutes of your time!
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