|
EPA Recommends:
- If you are buying a home or selling your home, have it tested
for radon.
- For a new home, ask if radon-resistant construction features
were used and if the home has been tested.
- 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.
- Take steps to prevent device interference when conducting a
radon test.
EPA estimates that radon causes thousands of cancer deaths in
the U.S. each year.
 |
* Radon is estimated to cause
about 21,000 lung cancer deaths per year, according to
EPA's
2003 Assessment of Risks from Radon in Homes (EPA 402-R-03-003).
The numbers of deaths from other causes are taken from the
Centers for Disease Control and Prevention's 1999-2001 National
Center for Injury Prevention and Control Report and 2002
National Safety Council Reports. |
This Guide answers important questions about radon and
lung cancer risk. It also answers questions about testing and
fixing for anyone buying or selling a home.
Radon Is a Cancer-Causing, Radioactive Gas
You cannot see, smell, or taste radon. But it still may be a
problem in your home. When you breathe air containing radon, you
increase your risk of getting lung cancer. In fact, the Surgeon
General of the United States has warned that radon is the second
leading cause of lung cancer in the United States today. If you
smoke and your home has high radon levels, your risk of lung cancer
is especially high.
|
EPA Risk Assessment for Radon in Indoor
Air
EPA has updated its estimate of the lung cancer risks from
exposure to radon in indoor air. The Agency's updated risk
assessment, "EPA
Assessment of Risks from Radon in Homes" [EPA
402-R-3-003]. EPA's assessment was based on the National
Academy of Sciences' (NAS) report on the "Health Effects of
Exposure to Radon" (BEIR
VI, 1999). The Agency now estimates that there are about
21,000 annual radon-related lung cancer deaths, an estimate
consistent with the NAS Report's findings.
|
You Should Test for Radon
Testing is the only way to find out your home's radon levels.
EPA and the Surgeon General recommend testing all homes below the
third floor for radon.
You Can Fix a Radon Problem
If you find that you have high radon levels, there are ways to
fix a radon problem. Even very high levels can be reduced to
acceptable levels.
If You Are Selling a Home...
EPA recommends that you test your home before putting it on the
market and, if necessary, lower your radon levels. Save the test
results and all information you have about steps that were taken
to fix any problems. This could be a positive selling point.
If You Are Buying a Home...
EPA recommends that you know what the indoor radon level is in
any home you consider buying. Ask the seller for their radon test
results. If the home has a radon-reduction system, ask the seller
for information they have about the system.
If the home has not yet been tested, you should have the housed
tested.
If you are having a new home built, there are features that can
be incorporated into your home during construction to reduce radon
levels.
The radon testing guidelines in this Guide have been
developed specifically to deal with the time-sensitive nature of
home purchases and sales, and the potential for radon device
interference. These guidelines are slightly different from the
guidelines in other EPA publications which provide radon testing
and reduction information for non-real estate situations.
This Guide recommends three short-term testing options
for real estate transactions. EPA also recommends testing a home
in the lowest level which is currently suitable for occupancy,
since a buyer may choose to live in a lower area of the home than
that used by the seller.
Top of page
a.
Radon
Has Been Found In Homes All Over the U.S.
Radon is a radioactive gas that has been found in homes all over
the United States. It comes from the natural breakdown of uranium in
soil, rock and water and gets into the air you breathe. Radon
typically moves up through the ground to the air above and into your
home through cracks and other holes in the foundation. Radon can
also enter your home through well water. Your home can trap radon
inside.
Any home can have a radon problem. This means new and old homes,
well-sealed and drafty homes, and homes with or without basements.
In fact, you and your family are most likely to get your greatest
radiation exposure at home. That is where you spend most of your
time.
Nearly 1 out of every 15 homes in the United States is estimated
to have an elevated radon level (4 pCi/L or more). Elevated levels
of radon gas have been found in homes in your state. Contact your
state radon
office for information about radon in your area.
b. EPA and the Surgeon General Recommend That
You Test Your Home
Testing is the only way to know if you and your family
are at risk from radon. EPA and the Surgeon General recommend
testing all homes below the third floor for radon.
You
cannot predict radon levels based on state, local, and neighborhood
radon measurements. Do not rely on radon test results taken in
other homes in the neighborhood to estimate the radon level in your
home. Homes which are next to each other can have different radon
levels. Testing is the only way to find out what your home's radon
level is.
In some areas, companies may offer different types of radon
service agreements. Some agreements let you pay a one-time fee that
covers both testing and radon mitigation, if needed. Contact your
state radon
office to find out if these are available in your state.
|
U.S. Surgeon General Health Advisory
"Indoor radon gas is the second-leading cause of lung cancer
in the United States and breathing it over prolonged periods can
present a significant health risk to families all over the
country. It's important to know that this threat is completely
preventable. Radon can be detected with a simple test and fixed
through well-established venting techniques." January 2005 |
Top of page
a.
If Your Home Has Already Been Tested for Radon...
If you are thinking of selling your home and you have already
tested your home for radon, review the Radon Testing Checklist
to make sure that the test was done correctly. If so, provide your
test results to the buyer.
No matter what kind of test you took, a potential buyer may ask
for a new test especially if:
- The Radon Testing Checklist items were not met;
- The last test is not recent, e.g., within two years;
- You have renovated or altered your home since you tested; or
- The buyer plans to live in a lower level of the house than was
tested, such as a basement suitable for occupancy but not
currently lived in.
A buyer may also ask for a new test if your state or local
government requires disclosure of radon information to buyers.
b. If Your Home Has Not Yet Been Tested
for Radon...
Have a test taken as soon as possible. If you can, test your home
before putting it on the market. You should test in the lowest
level of the home which is suitable for occupancy. This means
testing in the lowest level that you currently live in or a lower
level not currently used, but which a buyer could use for living
space without renovations.
The radon test result is important information about your home's
radon level. Some states require radon measurement testers to
follow a specific testing protocol. If you do the test yourself,
you should carefully follow the testing protocol for your area or
EPA's Radon Testing Checklist. If you hire a contractor to test
your residence, protect yourself by hiring a qualified
individual or company.
You can determine a service provider's qualifications to perform
radon measurements or to mitigate your home in several ways.
Check with your
state radon office. Many states require radon professionals
to be licensed, certified, or registered. Most states can provide
you with a list of knowledgeable radon service providers doing
business in the state. In states that don't regulate radon
services, ask the contractor if they hold a professional
proficiency or certification credential. Such programs usually
provide members with a photo-ID card, which indicates their
qualification and its expiration date. If in doubt, you should
check with their credentialing organization. Alternatively, ask
the contractor if they've successfully completed formal training
appropriate for testing or mitigation, e.g., a course in radon
measurement or radon mitigation.
| A note on what qualified may
mean: You should first call your
state radon
office for information on qualified radon service providers
and state-specific radon measurement or mitigation
requirements. See Section 9 for information
on which states have certification, licensing, or registration
programs. For up-to-date information on state radon program
offices, click this link. EPA's detailed and technical guidance
on radon measurement and mitigation is included in
Section 8; however, state requirements or guidance may be
more stringent. For more information on the private sector
radon credentialing programs, see
www.epa.gov/radon/radontest.html |
Top of page
a.
If the Home Has Already Been Tested for Radon...
If you are thinking of buying a home, you may decide to accept an
earlier test result from the seller, or ask the seller for a new
test to be conducted by a qualified radon tester. Before you accept
the seller's test, you should determine:
- The results of previous testing;
- Who conducted the previous test: the homeowner, a radon
professional, or some other person;
- Where in the home the previous test was taken, especially if
you may plan to live in a lower level of the home. For example,
the test may have been taken on the first floor. However, if you
want to use the basement as living space, test there; and
- What, if any, structural changes, alterations, or changes in
the heating, ventilation, and air conditioning (HVAC) system have
been made to the house since the test was done. Such changes may
affect radon levels.
If you accept the seller's test, make sure that the test followed
the Radon Testing Checklist.
If you decide that a new test is needed, discuss it with the
seller as soon as possible. If you decide to use a qualified radon
tester, check with your
state radon
office to see if they maintain a list of radon testing
companies. See also
www.epa.gov/radon/radontest.html
b. If the Home Has Not Yet Been Tested
for Radon...
Make sure that a radon test is done as soon as possible. Consider
including provisions in the contract specifying:
- Where the test will be located;
- Who should conduct the test;
- What type of test to do;
- When to do the test;
- How the seller and the buyer will share the test results and
test costs (if necessary); and
- When radon mitigation measures will be taken and who will pay
for them.
Make sure that the test is done in the lowest level of the
home suitable for occupancy. This means the lowest level that you
are going to use as living space which is finished or does not
require renovations prior to use. A state or local radon
official or qualified radon tester can help you make some of these
decisions.
If you decide to finish or renovate an unfinished area of the
home in the future, a radon test should be taken before starting the
project and after the project is finished. Generally, it is less
expensive to install a radon-reduction system before (or during)
renovations rather than afterwards.
Top of page
a. Why Should I Buy a Radon-Resistant Home?
Radon-resistant techniques work. When installed properly and
completely, these simple and inexpensive passive techniques can help
to reduce radon levels. In addition, installing them at the time of
construction makes it easier to reduce radon levels further if the
passive techniques don't reduce radon levels below 4 pCi/L.
Radon-resistant techniques may also help to lower moisture levels
and those of other soil-gases. Radon-resistant techniques:
 |
Making Upgrading Easy:
Even if built to be radon-resistant, every new home should be
tested for radon after occupancy. If you have a test result of
4 pCi/L or more, a vent fan can easily be added to the passive
system to make it an active system and further reduce radon
levels.
|
 |
Are Cost-Effective:
Building radon-resistant features into the house during
construction is easier and cheaper than fixing a radon problem
from scratch later. Let your builder know that radon-resistant
features are easy to install using common building materials.
|
 |
Save Money: When
installed properly and completely, radon-resistant techniques
can also make your home more energy efficient and help you save
on your energy costs. |
In a new home, the cost to install passive radon-resistant
features during construction is usually between $350 and $500. In
some areas, the cost may be as low as $100. A qualified mitigator
will charge about $300 to add a vent fan to a passive system, making
it an active system and further reducing radon levels. In an
existing home, it usually costs between $800 and $2,500 to
install a radon mitigation system.
b. What Are Radon-Resistant Features?
Radon-resistant techniques (features) may vary for different
foundations and site requirements. If you're having a house built,
you can learn about EPA's Model Standards (and architectural
drawings) and explain the techniques to your builder. If your new
house was built (or will be built) to be radon-resistant, it will
include these basic elements:
The techniques may vary for different foundations and site
requirements, but the basic elements are:
- Gas Permeable Layer
This layer is placed beneath the slab or flooring system to allow
the soil gas to move freely underneath the house. In many cases,
the material used is a 4-inch layer of clean gravel.
- Plastic Sheeting
Plastic sheeting is placed on top of the gas permeable layer and
under the slab to help prevent the soil gas from entering the
home. In crawlspaces, the sheeting is placed over the crawlspace
floor.
- Sealing and Caulking
All openings in the concrete foundation floor are sealed to reduce
soil gas entry into the home.
- Vent Pipe
A 3- or 4-inch gas-tight or PVC pipe (commonly used for plumbing)
runs from the gas permeable layer through the house to the roof to
safely vent radon and other soil gases above the house.
- Junction Box
An electrical junction box is installed in case an electric
venting fan is needed later.
Top of page
Radon testing is easy and the only way to find out if you have a
radon problem in your home.
a. Types of Radon Devices
Radon Test Device Placement
EPA recommends that testing device(s) be placed in the lowest
level of the home that could be used regularly, whether it is
finished or unfinished. Conduct the test in any space that could
be used by the buyer as a bedroom, play area, family room, den,
exercise room, or workshop. Based on their client's intended use
of the space, the qualified testing professional should identify
the appropriate test location and inform their client (buyer). Do
not test in a closet, stairway, hallway, crawl space or in an
enclosed area of high humidity or high air velocity. An enclosed
area may include a kitchen, bathroom, laundry room or furnace
room.
Since you cannot see or smell radon, special equipment is needed
to detect it. When you're ready to test your home, you can order a
radon test kit by mail from a qualified radon measurement services
provider or laboratory. You can also hire a qualified radon tester,
very often a home inspector, who will use a radon device(s) suitable
to your situation. The most common types of radon testing devices
are listed below. As new testing devices are developed, you may
want to check with your
state radon
office before you test to get the most up-to-date information.
Passive Devices
Passive radon testing devices do not need power to function.
These include charcoal canisters, alpha-track detectors,
charcoal liquid scintillation devices, and electret ion
chamber detectors which are available in hardware, drug, and
other stores; they can also be ordered by mail or phone. These
devices are exposed to the air in the home for a specified period
of time and then sent to a laboratory for analysis. Both
short-term and long-term passive devices are generally
inexpensive. Some of these devices may have features that offer
more resistance to test interference or disturbance than other
passive devices. Qualified radon testers may use any of these
devices to measure the home's radon level.
Active Devices
Active radon testing devices require power to function. These
include continuous radon monitors and continuous working level
monitors. They continuously measure and record the amount of
radon or its decay products in the air. Many of these devices
provide a report of this information which can reveal any unusual
or abnormal swings in the radon level during the test period. A
qualified tester can explain this report to you. In addition,
some of these devices are specifically designed to deter and
detect test interference. Some technically advanced active devices
offer anti-interference features. Although these tests may cost
more, they may ensure a more reliable result.
b. General Information for All Devices
A state or local radon official can explain the differences
between devices and recommend the ones which are most appropriate
for your needs and expected testing conditions.
Make sure to use a radon measurement device from a qualified
laboratory. Certain precautions should be followed to avoid
interference during the test period. See the Radon Testing
Checklist for more information on how to get a reliable test
result.
c. Preventing or Detecting Test Interference
There is a potential for test interference in real estate
transactions. There are several ways to prevent or detect test
interference:
 |
Use a test device that frequently
records radon or decay product levels to detect unusual swings; |
 |
Employ a motion detector to
determine whether the test device has been moved or testing
conditions have changed; |
 |
Use a proximity detector to reveal
the presence of people in the room which may correlate to
possible changes in radon levels during the test; |
 |
Record the barometric pressure to
identify weather conditions which may have affected the test; |
 |
Record the temperature record to
help assess whether doors and windows have been opened; |
 |
Apply tamper-proof seals to
windows to ensure closed house conditions; and |
 |
Have the seller/occupant sign a
non-interference agreement. |
Home buyers and sellers should consult a qualified radon test
provider about the use of these precautions.
d. Length of Time to Test
There Are Two General Ways To Test Your Home for Radon:
Because radon levels vary from day to day and season to season, a
short-term test is less likely than a long-term test to tell you
your year-round average radon level. However, if you need results
quickly, a short-term test may be used to decide whether to fix the
home.
Short-Term Testing
Whether you test for radon yourself or hire a state-certified
tester or a privately certified tester, all radon tests should be
taken for a minimum of 48 hours. A longer period of testing is
required for some devices.
The quickest way to test is with short-term tests. Short-term
tests remain in your home from two days to 90 days, depending on
the device. There are two groups of devices which are more
commonly used for short-term testing. The passive device group
includes alpha track detectors, charcoal canisters, charcoal
liquid scintillation detectors, and electret ion chambers.
The active device group consists of different types of
continuous monitors.
Long-Term Testing
Long-term tests remain in your home for more than 90 days.
Alpha track, and electret ion chamber detectors are
commonly used for this type of testing. A long-term test will give
you a reading that is more likely to tell you your home's
year-round average radon level than a short-term test. If time
permits (more than 90 days) long-term tests can be used to confirm
initial short-term results. When long-term test results are 4 pCi/L
or higher, EPA recommends fixing the home.
e. Doing a Short-Term Test...
When Choosing a Short-Term Testing Option...
There are trade-offs among the short-term testing options. Two
tests taken at the same time (simultaneous) would improve the
precision of this radon test. One test followed by another test
(sequential) would most likely give a better representation of the
seasonal average. Both active and passive devices may have
features which help to prevent test interference. Your state
radon office can help you decide which option is best.
If you are testing in a real estate transaction and you need
results quickly, any of the following three options for
short-term Tests are acceptable in determining whether the home
should be fixed. Any real estate test for radon should include
steps to prevent or detect device interference with the test
device.
|
Short-Term Testing Options |
What to do Next |
Passive:
Take two short-term tests at the same time in the same location
for at least 48 hours.
or
Take an initial short-term test for at least 48 hours.
Immediately upon completing the first test, do a second test
using an identical device in the same location as the first
test. |
Fix the home if the average of two tests is 4 pCi/L or more.
Fix the home if the average of the two tests is 4 pCi/L or
more. |
Active:
Test the home with a continuous monitor for at least 48 hours. |
Fix the home if the average radon level is 4 pCi/L or more. |
f. Using Testing Devices Properly for Reliable
Results
If You Do the Test Yourself
When you are taking a short-term test, close windows and doors
and keep them closed, except for normal entry and exit. If you are
taking a short-term test lasting less than four days, be sure to:
- Close your windows and outside doors at least 12 hours before
beginning the test;
- Do not conduct short-term tests lasting less than four days
during severe storms or periods of high winds;
- Follow the testing instructions and record the start time and
date;
- Place the test device at least 20 inches above the floor in a
location where it will not be disturbed and where it will be away
from drafts, high heat, high humidity, and exterior walls;
- Leave the test kit in place for as long as the test
instructions say; and
- Once you have finished the test, record the stop time and
date, reseal the package and return it immediately to the lab
specified on the package for analysis.
You should receive your test results within a few weeks. If you
need results quickly, you should find out how long results will take
and, if necessary, request expedited service.
If You Hire a Qualified Radon Tester
In many cases, home buyers and sellers may decide to have the
radon test done by a qualified radon tester who knows the proper
conditions, test devices, and guidelines for obtaining a reliable
radon test result. They can also:
- Evaluate the home and recommend a testing approach designed to
make sure you get reliable results;
- Explain how proper conditions can be maintained during the
radon test;
- Emphasize to occupants of a home that a reliable test result
depends on their cooperation. Interference with, or disturbance
of, the test or closed-house conditions will invalidate the test
result;
- Analyze the data and report measurement results; and
- Provide an independent test.
Your state
radon office may also have information about qualified radon
testers certification requirements. See also
www.epa.gov/radon/radontest.html
g. Interpreting Radon Test Results
Radon Test Results Reported in Two Ways
Your radon test results may be reported in either picoCuries
per liter of air (pCi/L) or working levels (WL). If your test
result is in pCi/L, EPA recommends you fix your home if your radon
level is 4 pCi/L or higher. If the test result is in WL, EPA
recommends you fix the home if the working level is 0.02 WL or
higher. Some states require WL results to be converted to pCi/L
to minimize confusion.
The average indoor radon level is estimated to be about 1.3 pCi/L;
roughly 0.4 pCi/L of radon is normally found in the outside air. The
U.S. Congress has set a long-term goal that indoor radon levels be
no more than outdoor levels. While this goal is not yet
technologically achievable for all homes, radon levels in many homes
can be reduced to 2 pCi/L or below.
Sometimes short-term tests are less definitive about whether the
home is at or above 4 pCi/L; particularly when the results are close
to 4 pCi/L. For example, if the average of two short-term tests is
4.1 pCi/L, there is about a 50% chance that the year-round average
is somewhat below 4 pCi/L.
However, EPA believes that any radon exposure carries some risk;
no level of radon is safe. Even radon levels below 4 pCi/L pose some
risk. You can reduce your risk of lung cancer by lowering your
radon level.
As with other environmental pollutants, there is some
uncertainty about the magnitude of radon health risks. However, we
know more about radon risks than risks from most other
cancer-causing substances. This is because estimates of radon risks
are based on data from human studies (underground miners).
Additional studies on more typical populations are under way.
Your radon measurement will give you an idea of your risk of
getting lung cancer from radon. Your chances of getting lung cancer
from radon depend mostly on:
- Your home's radon level;
- The amount of time you spend in your home; and
- Whether you are a smoker or have ever smoked.
Smoking combined with radon is an especially serious health risk.
If you smoke or are a former smoker, the presence of radon greatly
increases your risk of lung cancer. If you stop smoking now and
lower the radon level in your house, you will reduce your lung
cancer risk.
Based on information contained in the National Academy of
Sciences 1998 report, The Health Effects of Exposure to Indoor
Radon, your radon risk may be somewhat higher than shown;
especially if you have never smoked. It's never too late to
reduce your risk to lung cancer. Don't wait to test and fix a radon
problem. If you are a smoker, stop smoking.
Top of page
Radon Risk Comparison Charts
Your chances of getting lung cancer from radon depend
mostly on:
- How much radon is in your home
- The amount of time you spend in your home
- Whether you are a smoker or have ever smoked
Radon Risk If You Smoke
| Radon Level |
If 1,000 people who
smoked were exposed to this level over a lifetime*... |
The risk of cancer from
radon exposure compares to**... |
WHAT TO DO:
Stop smoking and... |
| 20 pCi/L |
About 260 people could get lung cancer |
250 times the risk of drowning |
Fix your home |
| 10 pCi/L |
About 150 people could get lung cancer |
200 times the risk of dying in a home fire |
Fix your home |
| 8 pCi/L |
About 120 people could get lung cancer |
30 times the risk of dying in a fall |
Fix your home |
| 4 pCi/L |
About 62 people could get lung cancer |
5 times the risk of dying in a car crash |
Fix your home |
| 2 pCi/L |
About 32 people could get lung cancer |
6 times the risk of dying from poison |
Consider fixing between 2 and 4 pCi/L |
| 1.3 pCi/L |
About 20 people could get lung cancer |
(Average indoor radon level) |
(Reducing radon
levels below 2 pCi/L is difficult.) |
| 0.4 pCi/L |
About 3 people could get lung cancer |
(Average outdoor radon level) |
Note: If you are a former smoker, your risk may
be lower.
* Lifetime risk of lung cancer deaths from EPA Assessment of
Risks from Radon in Homes (EPA 402-R-03-003).
** Comparison data calculated using the Centers for Disease
Control and Prevention's 1999-2001 National Center for Injury
Prevention and Control Reports. |
Radon Risk If You've Never Smoked
| Radon Level |
If 1,000 people who
never smoked were exposed to this level over a lifetime*... |
The risk of cancer from
radon exposure compares to**... |
WHAT TO DO: |
| 20 pCi/L |
About 36 people could get lung cancer |
35 times the risk of drowning |
Fix your home |
| 10 pCi/L |
About 18 people could get lung cancer |
20 times the risk of dying in a home fire |
Fix your home |
| 8 pCi/L |
About 15 people could get lung cancer |
4 times the risk of dying in a fall |
Fix your home |
| 4 pCi/L |
About 7 people could get lung cancer |
The risk of dying in a car crash |
Fix your home |
| 2 pCi/L |
About 4 person could get lung cancer |
The risk of dying from poison |
Consider fixing between 2 and 4 pCi/L |
| 1.3 pCi/L |
About 2 people could get lung cancer |
(Average indoor radon level) |
(Reducing radon levels below
2 pCi/L is difficult.) |
| 0.4 pCi/L |
|
(Average outdoor radon level) |
Note: If you are a former smoker, your risk may
be higher.
* Lifetime risk of lung cancer deaths from EPA Assessment of
Risks from Radon in Homes (EPA 402-R-03-003).
** Comparison data calculated using the Centers for Disease
Control and Prevention's 1999-2001 National Center for Injury
Prevention and Control Reports. |
It's never too late to reduce your risk of
lung cancer. Don't wait to test and fix a radon problem. If you
are a smoker, stop smoking.
Top of page
Radon
Testing Checklist
For reliable test results, follow this Radon Testing Checklist
carefully. Testing for radon is not complicated. Improper testing
may yield inaccurate results and require another test. Disturbing
or interfering with the test device, or with closed-house
conditions, may invalidate the test results and is illegal in some
states. If the seller or qualified tester cannot confirm that all
items have been completed, take another test.
Before Conducting a Radon Test:
- Notify the occupants of the importance of proper testing
conditions. Give the occupants written instructions or a copy of
this Guide and explain the directions carefully.
- Conduct the radon test for a minimum of 48 hours; some test
devices have a minimum exposure time greater than 48 hours.
- When doing a short-term test ranging from 2-4 days, it is
important to maintain closed-house conditions for at least 12
hours before the beginning of the test and during the entire test
period.
- When doing a short-term test ranging from 4-7 days, EPA
recommends that closed-house conditions be maintained.
- If you conduct the test yourself, use a qualified radon
measurement device and follow the laboratory's instructions. Your
state may be able to provide you with a list of do-it-yourself
test devices available from qualified laboratories.
- If you hire someone to do the test, hire only a qualified
individual. Some states issue photo identification (ID) cards;
ask to see it. The tester's ID number, if available, should be
included or noted in the test report.
- The test should include method(s) to prevent or detect
interference with testing conditions or with the testing device
itself.
- If the house has an active radon-reduction system, make sure
the vent fan is operating properly. If the fan is not operating
properly, have it (or ask to have it) repaired and then test.
During a Radon Test:
Closed-house conditions means keeping all windows closed, keeping
doors closed except for normal entry and exit, and not operating
fans or other machines which bring in air from outside. Fans that
are part of a radon-reduction system or small exhaust fans
operating for only short periods of time may run during the test.
- Maintain closed-house conditions during he entire time of a
short term test, especially for tests shorter than one week in
length.
- Operate the home's heating and cooling systems normally during
the test. For tests lasting less than one week, operate only
air-conditioning units which recirculate interior air.
- Do not disturb the test device at any time during the test.
- If a radon-reduction system is in place, make sure the system
is working properly and will be in operation during the entire
radon test.
After a Radon Test:
- If you conduct the test yourself, be sure to promptly return
the test device to the laboratory. Be sure to complete the
required information, including start and stop times, test
location, etc.
- If an elevated level is found, fix the home. Contact a
qualified radon-reduction contractor about lowering the radon
level. EPA recommends that you fix the home when the radon level
is 4 pCi/L or more.
- Be sure that you or the radon tester can demonstrate or
provide information to ensure that the testing conditions were not
violated during the testing period.
Top of page
a. High Radon Levels Can be Reduced
EPA recommends that you take action to reduce your home's indoor
radon levels if your radon test result is 4 pCi/L or higher. It is
better to correct a radon problem before placing your home on the
market because then you have more time to address a radon problem.
If elevated levels are found during the real estate transaction,
the buyer and seller should discuss the timing and costs of the
radon reduction. The cost of making repairs to reduce radon levels
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 can range from
$800 to about $2,500.
b.
How To Lower The Radon Level In Your Home
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 alone to limit radon entry. Sealing alone
has not been shown to lower radon levels significantly or
consistently.
In most cases, a system with a vent pipe(s) and fan(s) is used
to reduce radon. These "sub-slab depressurization" systems do not
require major changes to your home. Similar systems can also be
installed in homes with crawl space. These systems prevent radon
gas from entering the home from below the concrete floor and from
outside the foundation. Radon mitigation contractors may use other
methods that may also work in your home. The right system depends on
the design of your home and other factors.
Techniques for reducing radon are discussed in EPA's
"Consumer's
Guide to Radon Reduction." As with any other household
appliance, there are costs associated with the operation of the
radon-reduction system.
|
Radon and home renovations
If you are planning any major renovations, such as converting
an unfinished basement area into living space, it is especially
important to test the area for radon before you begin.
If your test results indicate an elevated radon level,
radon-resistant techniques can be inexpensively included as part
of the renovation. Major renovations can change the level of
radon in any home. Test again after the work is completed. |
You should also test your home again after it is fixed to be sure
that radon levels have been reduced. If your living patterns change
and you begin occupying a lower level of your home (such as a
basement) you should retest your home on that level. In addition, it
is a good idea to retest your home sometime in the future to be sure
radon levels remain low.
c. Selecting a Radon-Reduction (Mitigation)
Contractor
Select a qualified radon-reduction contractor to reduce the radon
levels in your home. Any mitigation measures taken or system
installed in your home must conform to your state's regulations. In
states without regulations covering mitigation, the system should
conform to EPA's
Radon
Mitigation Standards.
EPA recommends that the mitigation contractor review the radon
measurement results before beginning and radon-reduction work. Test
again after the radon mitigation work has been completed to confirm
that previous elevated levels have been reduced. EPA recommends
that the test be conducted by an independent qualified radon
tester. See
www.epa.gov/radon/radontest.html for more information.
d. What Can a Qualified Radon-Reduction
Contractor Do for You?
A qualified radon-reduction (mitigation) contractor should be
able to:
- Review testing guidelines and measurement results, and
determine if additional measurements are needed;
- Evaluate the radon problem and provide you with a detailed,
written proposal on how radon levels will be lowered;
- Design a radon-reduction system;
- Install the system according to EPA standards, or state or
local codes; and
- Make sure the finished system effectively reduces radon levels
to acceptable levels.
Choose a radon mitigation contractor to fix your radon problem
just as you would for any other home repair. You may want to get
more than one estimate, ask for and check their references. Make
sure the person you hire is qualified to install a mitigation
system. Some states regulate or certify radon mitigation services
providers.
Be aware that a potential conflict of interest exists if the same
person or firm performs the testing and installs the mitigation
system. Some states may require the homeowner to sign a waiver in
such cases. If the same person or firm does the testing and
mitigation, make sure the testing is done in accordance with the
Radon Testing Checklist. Contact your
state radon office for more information.
e. Radon in Water
The radon in your home's indoor air can come from two sources,
the soil or your water supply. Compared to radon entering your home
through water, radon entering your home through soil is a much
larger risk. If you've tested for radon in air and have elevated
radon levels and your water comes from a private well, have your
water tested. The devices and procedures for testing your home's
water supply are different from those used for measuring radon in
air.
The radon in your water supply poses an inhalation risk and an
ingestion risk. Research has shown that your risk of lung cancer
from breathing radon in air is much larger than your risk of stomach
cancer from swallowing water with radon in it. Most of your risk
from radon in water comes from radon released into the air when
water is used for showering and other household purposes.
Radon in your home's water in not usually a problem when its
source is surface water. A radon in water problem is more likely
when its source is ground water, e.g., a private well or a public
water supply system that uses ground water. Some public water
systems treat their water to reduce radon levels before it is
delivered to your home. If you are concerned that radon may be
entering your home through the water and your water comes from a
public water supply, contact your water supplier.
If you've tested your private well and have a radon in water
problem, it can be fixed. Your home's water supply can be treated in
one of two ways. Point-of-entry treatment can effectively remove
radon from the water before it enters your home. Point-of-entry
treatment usually employs either granular activated carbon (GAC)
filters or aeration devices. While GAC filters usually cost less
than aeration devices, filters can collect radioactivity and may
require a special method of disposal. Point-of-use treatment
devices remove radon from your water at the tap, but only treat a
small portion of the water you use, e.g., the water you drink.
Point-of-use devices are not effective in reducing the risk from
breathing radon released into the air from all water used in the
home.
For information on radon in water, testing and treatment, and
existing or planned radon in drinking water standards, or for
general help, call EPA's Drinking Water Hotline at (800) 426-4791 or
visit
www.epa.gov/safewater/radon.html. If your water comes from a
private well, you can also contact your state radon office.
Top of page
MYTH: Scientists are not sure that radon really is a problem.
FACT: Although some scientists dispute the
precise number of deaths due to radon, all the major health
organizations (like the Centers for Disease Control and
Prevention, the American Lung Association and the American Medical
Association) agree with estimates that radon causes thousands of
preventable lung cancer deaths every year. This is especially true
among smokers, since the risk to smokers is much greater than to
non-smokers.
MYTH: Radon testing is difficult, time-consuming and
expensive.
FACT: Radon testing is easy. You can test
your home yourself or hire a qualified radon test company. Either
approach takes only a small amount of time and effort.
MYTH: Radon testing devices are not reliable and are difficult
to find.
FACT: Reliable testing devices are available
from qualified radon testers and companies. Reliable testing
devices are also available by phone or mail-order, and can be
purchased in hardware stores and other retail outlets. Call your
state radon
office for help in identifying radon testing companies.
MYTH: Homes with radon problems can't be fixed.
FACT: There are simple solutions to radon
problems in homes. Hundreds of thousands of homeowners have
already fixed radon problems in their homes. Radon levels can be
readily lowered for $800 to $2,500 (with an average cost of
$1,200).. Call your
state radon
office for help in identifying qualified mitigation
contractors.
MYTH: Radon affects only certain kinds of homes.
FACT: House construction can affect radon
levels. However, radon can be a problem in homes of all types:
old homes, new homes, drafty homes, insulated homes, homes with
basements, and homes without basements. Local geology,
construction materials, and how the home was built are among the
factors that can affect radon levels in homes.
MYTH: Radon is only a problem in certain parts of the country.
FACT: High radon levels have been found in
every state. Radon problems do vary from area to area, but the
only way to know your radon level is to test.
MYTH: A neighbor's test result is a good indication of whether
your home has a problem.
FACT: It's not. Radon levels can vary greatly
from home to home. The only way to know if your home has a radon
problem is to test it.
MYTH: Everyone should test their water for radon.
FACT: Although radon gets into some homes
through water, it is important to first test the air in the home
for radon. If your water comes from a public water supply that
uses ground water, call your water supplier. If high radon levels
are found and the home has a private well, call the Safe Drinking
Water Hotline at 1 800-426-4791 for information on testing your
water.
MYTH: It's difficult to sell homes where radon problems have
been discovered.
FACT: Where radon problems have been fixed,
home sales have not been blocked or frustrated. The added
protection is some times a good selling point.
MYTH: I've lived in my home for so long, it doesn't make sense
to take action now.
FACT: You will reduce your risk of lung cancer
when you reduce radon levels, even if you've lived with a radon
problem for a long time.
MYTH: Short-term tests can't be used for making a decision
about whether to fix your home.
FACT: A short-term test, followed by a second
short-term test* can be used to decide whether to fix your home.
However, the closer the average of your two short-term tests is to
4 pCi/L, the less certain you can be about whether your year-round
average is above or below that level. Keep in mind that radon
levels below 4 pCi/L still pose some risk. Radon levels can be
reduced in most homes to 2 pCi/L or below.
* If the radon test is part of a real estate transaction, the
result of two short-term tests can be used in deciding whether to
mitigate. For more information, see EPA's "Home
Buyer's and Seller's Guide to Radon".
Top of page
a. World Wide Websites (EPA)
These are EPA's most important websites for information on radon
and indoor air quality. All the EPA publications listed in this
section are available here on EPA's Website.
- EPA's main radon
page. Includes links to the NAS radon report, radon-resistant
new construction, the map of radon zones, radon publications,
hotlines and more.
- State Radon
Contacts. Provides detailed information on contacting your
state's radon office, including links to some state websites.
State indoor air quality contact are also included.
- EPA's Radon
Publications. Offers the full text version of EPA's most
popular radon publications, including the Consumer's Guide to
Radon Reduction, the Citizen's Guide to Radon, and the Model
Standards and Techniques for Control of Radon in New Residential
Buildings, and others.
- EPA's main page on
Indoor Air Quality. Includes information on indoor risk
factors, e.g., asthma, secondhand smoke, carbon monoxide, duct
cleaning, ozone generating devices, indoor air cleaners, flood
cleanup, etc.
- EPA's main
page on radon in water. Includes information on statutory
requirements and links to the drinking water standards program.
b. Radon Hotlines (Toll-Free)
EPA supports the following hotlines to best serve consumers with
radon-related questions and concerns.
- 1-800-SOS-RADON (767-7236). Radon Hotline, operated by
the National Safety Council (NSC) in partnership with EPA. Order
radon test kits by phone.
- 1-800-55RADON (557-2366). For live help with your
radon questions. Operated by the National Safety Council (NSC) in
partnership with EPA.
- 1-800-438-4318. The Indoor Air Quality (IAQ)
Information Clearinghouse is privately operated under contract to
EPA. You can get general information on radon and indoor air
quality issues.
- 1-800-426-4791. Safe Drinking Water Hotline, privately
operated under contract to EPA. For general information on
drinking water, radon in water, testing and treatment, and radon
drinking water standards.
c. Printed Documents
Radon Risk and Testing
 |
Home Buyer's and Seller's Guide
to Radon |
This booklet is intended for anyone who is buying or selling a
home, real estate and relocation professionals, home inspectors
and others. This revised edition includes several
changes: Recent data comparing common causes of death to
radon-related deaths (inside front cover); Information on EPA’s
Assessment of Risks from Radon in Homes (p.1); The U.S. Surgeon
General’s 2005 National Radon Health Advisory (p.4 and back
cover); A new table comparing the relative risk for people that
smoke and people that have never smoked (p.18).
Single copies are available free from the following sources
(multiple copies may be available in some instances; ask for
details):
Single or multiple copies are available for a fee from the
following sources (ask for details):
Reducing Radon Levels in a Home
 |
Consumer's
Guide to Radon Reduction (EPA 402-K-06-094, December
2006). The consumer's basic source of information on how to
reduce radon levels in a home's indoor air. It includes
information about the key mitigation system components,
installation and operating costs, radon health risks, and
testing (when not in a real estate transaction). |
Building a New Home to be Radon-Resistant
 |
Appendix F: Radon Control
Methods (IRC, 2003). Published in the International
Residential Code by the International Code Council (ICC) as a
guide to building radon-resistant homes. Available from the ICC,
5203 Leesburg Pike, Suite 600, Falls Church, VA 22041-3401.
Contact information: 1-888-ICC-SAFE (1-888-422-7233) and at
www.iccsafe.org

|
 |
Radon Control Methods
(Section 49.2.5) Published in the National Fire Protection
Association's (NTPA, 2003) Building Construction and Safety
Code: NFPA 5000. NFPA, 1 Batterymarch Park, Quincy, MA
02169-7471. Contact information: (617) 770-3000 and at
www.nfpa.org

|
 |
Model Standards and Techniques
for Control of Radon in New Residential Buildings (EPA
402-R-94-009, March 1994) These model standards were developed
by EPA in conjunction with the home building industry. They
provide technical details on how to make radon-resistant
features an integral part of a new home during construction. A
must for builders or anyone building a new or custom home. |
Radon Technical Guidance
 |
Standard Practice for
Installing Radon Mitigation Systems in Existing Low-Rise
Residential Buildings (EPA 402-K-93-007). Published by the
American Society for Testing and Materials (ASTM) International
(ASTMI) as Standard Practice E-2121-03, (February 10, 2003). A
single copy per request is available only as a hard (printed)
copy from IAQ-Info (1-800-438-4318).
|
 |
Protocols for Radon and Radon
Decay Product Measurements in Homes (EPA 402-R-92-003, June
1993). This document is intended for use by qualified radon
measurement technicians and testers, and laboratories that
analyze radon devices and prepare radon test results reports.
These protocols were written to guide routine radon measurements
(Citizen's Guide) and those made in conjunction with real estate
transactions (Home Buyer's and Seller's Guide). Available here
as a
PDF file (PDF, 47 pp, 675KB,
About PDF).
|
 |
Indoor
Radon and Radon Decay Product Measurement Device Protocols
(EPA 402-R-92-004, July 1992). This document is intended for
use by qualified radon measurement technicians and testers. It
contains detailed technical information on the types of radon
measurement devices, their proper use and maintenance, and
quality assurance procedures. These protocols were written to
guide routine radon measurements (Citizen's Guide) and those
made in conjunction with real estate transactions (Home Buyer's
and Seller's Guide). |
Top of page
9./10. State Radon Offices
and EPA Regional Offices
Go to our Where You Live page (www.epa.gov/iaq/whereyoulive.html
and click on your state or EPA Region for a list of contacts.
|
U.S. Surgeon General Health Advisory
"Indoor radon gas is the second-leading cause of lung cancer
in the United States and breathing it over prolonged periods can
present a significant health risk to families all over the
country. It's important to know that this threat is completely
preventable. Radon can be detected with a simple test and fixed
through well-established venting techniques." January 2005 |
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