U.S. Environmental Protection Agency
U.S. Department of Health and Human Services (Centers for Disease
Control)
U.S. Public Health Service
402-K92-001
May 1992
EPA Air and Radiation (ANR-464)
"A CITIZEN'S GUIDE TO RADON"
The Guide to Protecting Yourself and Your Family from Radon
Radon is estimated to cause about 14,000 deaths per year. However, this number could range from 7,000 to 30,000 deaths per year The numbers of deaths from other causes are taken from 1990 National Safety Council reports.
EPA Recommends:
ù Test your home for radon -- it's easy and inexpensive.
ù Fix your home if your radon level is 4 picocuries per liter (pCi/L) or higher.
ù Radon levels less than 4 pCi/L still pose a risk, and in many cases may be reduced.
OVERVIEW
Radon is a cancer-causing, radioactive gas.
You can't see radon. And you can't smell it or taste it.
But it may be a problem in your home.
Radon is estimated to cause many thousands of deaths each
year. That's because when you breathe air containing radon, you
can get lung cancer. In fact, the Surgeon General has warned
that radon is the second leading cause of lung cancer in the
United States today. Only smoking causes more lung cancer
deaths. If you smoke and your home has high radon levels, your
risk of lung cancer is especially high.
Radon can be found all over the U.S.
Radon comes from the natural (radioactive) breakdown of uranium in soil, rock and water and gets into the air you breathe. Radon can be found all over the U.S. It can get into any type of building--homes, offices, and schools--and build up to high levels. But you and your family are most likely to get your greatest exposure at home. That's where you spend most of your time.
You should test for radon.
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. EPA also
recommends testing in schools.
Testing is inexpensive and easy--it should only take a few
minutes of your time. Millions of Americans have already tested
their homes for radon
You can fix a radon problem.
There are simple ways to fix a radon problem that aren't too costly. Even very high levels can be reduced to acceptable levels.
HOW DOES RADON GET INTO YOUR HOME?
Radon is a radioactive gas. lt comes from the natural decay of uranium that is found in nearly all soils. It typically moves up through the ground to the air above and into your home through cracks and other holes in the foundation. Your home traps radon inside, where it can build up. Any home may have a radon problem. This means new and old homes, well-sealed and drafty homes, and homes with or without basements. Radon from soil gas is the main cause of radon problems. Sometimes radon enters the home through well water (see "Radon in Water" below). In a small number of homes, the building materials can give off radon, too. However, building materials rarely cause radon problems by themselves.
RADON GETS IN THROUGH:
HOW TO TEST YOUR HOME
You can't see radon, but it's not hard to find out if you
have a radon problem in your home. All you need to do is test
for radon. Testing is easy and should only take a few minutes of
your time.
The amount of radon in the air is measured in "picocuries
per liter of air," or "pCi/L." Sometimes test results are
expressed in Working Levels (WL) rather than picocuries per liter
(pCi/L). There are many kinds of low-cost "do it yourself" radon
test kits you can get through the mail and in hardware stores and
other retail outlets. Make sure you buy a test kit that has
passed EPA's testing program or is state-certified. These kits
will usually display the phrase "Meets EPA Requirements." If you
prefer, or if you are buying or selling a home, you can hire a
trained contractor to do the testing for you. Make certain you
hire an EPA-qualified or state-certified radon tester.
Call your state radon office (see below) for a list of these
testers.
There are Two General Ways to Test for Radon:
SHORT-TERM TESTING: The quickest way to test is with short-term tests. Short-term tests remain in your home for two days to 90 days, depending on the device. "Charcoal canisters," "alpha track," "electret ion chamber," "continuous monitors," and "charcoal liquid scintillation" detectors are most commonly used for short-term testing. Because radon levels tend to 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. If you need results quickly, however, a short-term test followed by a second short-term test may be used to decide whether to fix your home.
LONG-TERM TESTING: Long-term tests remain in your home for more than 90 days. "Alpha track" and "electret" 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.
How To Use a Test Kit:
Follow the instructions that come with your test kit. If you are doing a short-term test, close your windows and outside doors and keep them closed as much as possible during the test. (If you are doing a short-term test lasting just 2 or 3 days, be sure to close your windows and outside doors at least 12 hours before beginning the test, too. You should not conduct short-term tests lasting just 2 or 3 days during unusually severe storms or periods of unusually high winds.) The test kit should be placed in the lowest lived-in level of the home (for example, the basement if it is frequently used, otherwise the first floor). It should be put in a room that is used regularly (like a living room, playroom, den or bedroom) but not your kitchen or bathroom. Place the kit at least 20 inches above the floor in a location where it won't be disturbed--away from drafts, high heat, high humidity, and exterior walls. Leave the kit in place for as long as the package says. Once you've finished the test, reseal the package and send it to the lab specified on the package right away for study. You should receive your test results within a few weeks.
Testing is easy and should only take a few minutes of your time.
EPA Recommends the Following Testing Steps:
Step 1. Take a short-term test. If your result is 4 pCi/L or higher (0.02 Working Levels [WL] or higher) take a follow-up test (Step 2) to be sure.
Step 2. Follow up with either a long-term test or a second short-term test. For a better understanding of your year-round average radon level, take a long-term test. If you need results quickly, take a second short-term test. The higher your initial short-term test result, the more certain you can be that you should take a short-term rather than a long-term follow up test. If your first short-term test result is several times the action level--for example, about 10 pCi/L or higher--you should take a second short-term test immediately
Step 3. If you followed up with a long-term test: Fix your home if your long-term test result is 4 pCi/L or more (0.02 Working Levels [WL] or higher). If you followed up with a seconds short-term test: The higher your short-term results, the more certain you can be that you should fix your home. Consider fixing your home if the average of your first and second test is 4 pCi/L or higher (0.02 Working Levels [WL] or higher).
WHAT YOUR TEST RESULTS MEAN
The average indoor radon level is estimated to be about 1.3 pCi/L, and about 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 in all cases, most homes today can be reduced to 2 pCi/L or below. Sometimes short-term tests are less definitive about whether or not your home is above 4 pCi/L. This can happen when your results are close to 4 pCi/L. For example, if the average of your two short-term test results is 4.1 pCi/L, there is about a 50% chance that your 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, and you can reduce your risk of lung cancer by lowering your radon level. 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. Even if your test result is below 4 pCi/L, you may want to test again sometime in the future.
Radon and Home Sales
More and more, home buyers and renters are asking about radon levels before they buy or rent a home. Because real estate sales happen quickly, there is often little time to deal with radon and other issues. The best thing to do is to test for radon NOW and save the results in case the buyer is interested in them. Fix a problem if it exists so it won't complicate your home sale. If you are planning to move, call your state radon office (see below) for EPA's pamphlet "Home Buyer's and Seller's Guide to Radon," which addresses some common questions. During home sales:
--Buyers often ask if a home has been tested, and if elevated levels were reduced.
--Buyers frequently want tests made by someone who is not involved in the home sale. Your state office (see below) has a list of qualified testers.
--Buyers might want to know the radon levels in areas of the home (like a basement they plan to finish) that the seller might not otherwise test.
Today many homes are built to prevent radon from coming in. Your state or local area may require these radon-resistant construction features. Radon-resistant construction features usually keep radon levels in new homes below 2 pCi/L. If you are buying or renting a new home, ask the owner or builder if it has radon-resistant features.
Test your home now and save results. If you find high radon levels, fix our home before you decide to sell it.
RADON IN WATER
If you've tested the air in your home and found a radon problem, and your water comes from a well, have your water tested
Compared with radon entering the home through soil, radon
entering the home through water will in most cases be a small
source of risk. Radon gas can enter the home through well water.
It can be released into the air you breathe when water is used
for showering and other household uses. Research suggests that
swallowing water with high radon levels may pose risks, too,
although risks from swallowing water containing radon are
believed to be much lower than those from breathing air
containing radon.
While radon in water is not a problem in homes served by
most public water supplies, it has been found in well water. If
you've tested the air in your home and found a radon problem, and
your water comes from a well, contact a lab certified to measure
radiation in water to have your water tested. If you're on a
public water supply and are concerned that radon may be entering
your home through the water, call your public water supplier.
Radon problems in water can be readily fixed. The most
effective treatment is to remove radon from the water before it
enters the home. This is called point-of-entry treatment.
Treatment at your water tap is called point-of-use treatment.
Unfortunately, point-of-use treatment will not reduce most of the
inhalation risk from radon.
Call your state office (see below) or the EPA Drinking
Water Hot line (800-426-4791) for more information on radon in
water.
HOW TO LOWER THE RADON LEVEL IN YOUR HOME
Since there is no known safe level of radon, there can
always be some risk. But the risk can be reduced by lowering the
radon level in your home.
A variety of methods are used to reduce radon in your home.
In some cases, sealing cracks in floors and walls may help to
reduce radon. In other cases, simple systems using pipes and
fans may be used to reduce radon. Such systems are called
"sub-slab depressurization," and do not require major changes to
your home. These systems remove radon gas from below the
concrete floor and the foundation before it can enter the home.
Similar systems can also be installed in houses with crawl
spaces. Radon contractors use other methods that may also work
in your home. The right system depends on the design of your
home and other factors.
Ways to reduce radon in your home are discussed in EPA's
"Consumer's Guide to Radon Reduction." You can get a copy from
your state radon office (see below.
The cost of making repairs to reduce radon depends on how
your home was built and the extent of the radon problem. 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 house costs about $1,200 for a contractor to fix,
although this can range from about $500 to about $2,500.
Lowering high radon levels requires technical knowledge and
special skills. You should use a contractor who is trained to
fix radon problems. The EPA Radon Contractor Proficiency (RCP)
Program tests these contractors. EPA provides a list of RCP
contractors to state radon offices (see below). A contractor who
has passed the EPA test will carry a special RCP identification
card. A trained RCP contractor can study the radon problem in
your home and help you pick the right treatment method.
Check with your state radon office (see below) for names of
qualified or state certified radon contractors in your area.
Picking someone to fix your radon problem is much like choosing a
contractor for other home repairs--you may want to get references
and more than one estimate.
If you plan to fix the problem in your home yourself, you
should first contact your state radon office (see below) for
EPA's technical guide, "Radon Reduction Techniques for Detached
Houses."
You should also test your home again after it is fixed to be
sure that radon levels have been reduced. Most radial reduction
systems include a monitor that will alert you if the system needs
servicing. In addition, it's a good idea to retest your home
sometime in the future to be sure radon levels remain low.
Radon and Home Renovations
If you are planning any major structural renovation, such as converting an unfinished basement area into living space, it is especially important to test the area for radon before you begin the renovation. If your test results indicate a radon problem. radon-resistant techniques can be inexpensively included as part of the renovation. Because major renovations can change the level of radon in any home, always test again after work is completed. Most homes can be fixed for about the same cost as other common home repairs.
THE RISK OF LIVING WITH RADON
Radon gas decays into radioactive particles that can get
trapped in your lungs when you breathe. As they break down
further, these particles release small bursts of energy. This
can damage lung tissue and lead to lung cancer over the course of
your lifetime. Not everyone exposed to elevated levels of radon
will develop lung cancer. And the amount of time between
exposure and the onset of the disease may be many years.
Like 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 studies of cancer in humans (underground
miners). Additional studies on more typical populations are
under way.
Smoking combined with radon is an especially serious health
risk. Stop smoking and lower your radon level to reduce your
lung cancer risk.
Children have been reported to have greater risk than adults
of certain types of cancer from radiation, but there are
currently no conclusive data on whether children are at greater
risk than adults from radon.
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
Scientists are more certain about radon risks than risks from most other cancer-causing substances.
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
compared to . . . WHAT TO DO:
Stop smoking and
. . . 20 pCi/L About 135 people
could get lung
cancer 100 times the risk
of drowning Fix your home 10 pCi/L About 71 people
could get lung
cancer 100 times the risk
of dying in a home
fire Fix your home 8 pCi/L About 57 people
could get lung
cancer Fix your home 4 pCi/L About 29 people
could get lung
cancer 100 times the risk
of dying in an
airplane crash Fix your home 2 pCi/L About 15 people
could get lung
cancer 2 times the risk of
dying in a car crash Consider fixing
between 2 and 4
pCi/L 1.3 pCi/L About 9 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.
RADON RISK IF YOU HAVE 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 8 people could
get lung cancer The risk of being
killed in a violent
crime Fix your home 10 pCi/L About 4 people could
get lung cancer Fix your home 8 pCi/L About 3 people could
get lung cancer 10 times the risk of
dying in an airplane
crash Fix your home 4 pCi/L About 2 people could
get lung cancer The risk of drowning Fix your home 2 pCi/L About 1 person could
get lung cancer The risk of dying in
a home fire Consider fixing
between 2 and 4
pCi/L 1.3 pCi/L Less than 1 person
could get lung
cancer (Average indoor
radon level)
(Reducing radon
levels below 2 pCi/L
is difficult) 0.4 pCi/L Less than 1 person
could get lung
cancer (Average outdoor
radon level)
Note If you are a former smoker, your risk may be higher. Some Common Myths About Radon
MYTH: Scientists aren't sure radon really is a problem. FACT: Although some scientists dispute the precise number of deaths due to radon, all 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 inexpensive and easy -- it should only take a little of your time.
MYTH: Radon test kits are not reliable and are difficult to find. FACT: Reliable test kits are available through the mail, in hardware stores and other retail outlets. Call your state radon office (see below) for a list of test kit companies that have met EPA requirements for reliability or are state-certified.
MYTH: Homes with radon problems can't be fixed. FACT: There are simple solutions to radon problems in homes. Thousands of homeowners have already fixed radon problems in their homes. Radon levels can be readily lowered for about $500 to $2,000. Call your state radon office (see below) for a list of contractors that have met EPA requirements or are state-certified.
MYTH: Radon only affects certain kinds of homes. FACT: House construction can affect radon levels. However, radon can be a problem in old homes, new homes, drafty homes, insulated homes, homes without basements.
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 vary 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: While radon gets into some homes through the water, you should first test the air in your home for radon. If you find high levels and have a well, contact a lab certified to measure radiation in water to have your water tested.
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 sometimes 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 can 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 may
be used to decide whether to fix your home. However, the closer
the average of your two short-term tests is to 4pCi/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 4pCi/L
still pose some risk. Radon levels can be reduced in most homes
to 2 pCi/L or below.
STATE RADON CONTACTS
ALABAMA 800-582-1866
ALASKA 800-478-8324
ARIZONA 602-255-4845
ARKANSAS 501-661-2301
CALIFORNIA 800-745-7236
COLORADO 800-846-3986
CONNECTICUT 203-566-3122
DELAWARE 800-554-4636
D.C. 202-727-5728
FLORIDA 800-543-8279
GEORGIA 800-745-0037
HAWAII 808-586-4700
IDAHO 800-445-8647
ILLINOIS 800-325-1245
INDIANA 800-272-9723
IOWA 800-383-5992
KANSAS 913-296-6183
KENTUCKY 502-564-3700
LOUISIANA 800-256-2494
MAINE 800-232-0842
MARYLAND 800-872-3666
MASSACHUSETTS 413-586-7525
MICHIGAN 800-723-6642
MINNESOTA 800-798-9050
MISSISSIPPI 800-626-7739
MISSOURI 800-669-7236
MONTANA 406-444-3671
NEBRASKA 800-334-9491
NEVADA 702-687-5394
NEW HAMPSHIRE 800-852-3345 X4674
NEW JERSEY 800-648-0394
NEW MEXICO 505-827-4300
NEW YORK 800-458-1158
NORTH CAROLINA 919-571-4141
NORTH DAKOTA 701-221-5188
OHIO 800-523-4439
OKLAHOMA 405-271-1902
OREGON 503-731-4014
PENNSYLVANIA 800-237-2366
PUERTO RICO 809-767-3563
RHODE ISLAND 401-277-2438
SOUTH CAROLINA 800-768-0362
SOUTH DAKOTA 800-438-3367
TENNESSEE 800-232-1139
TEXAS 512-834-6688
UTAH 800-536-4250
VERMONT 800-640-0601
VIRGINIA 800-468-0138
WEST VIRGINIA 800-922-1255
WISCONSIN 800-267-4795
WYOMING 800-458-5847
National Radon Hotline: 1 800/SOS-RADON
FOR FURTHER INFORMATION
For more information on how to reduce your radon health risk, ask your state radon office to send you these guides:
Home Buyer's and Seller's Guide to Radon
Radon in Schools
Radon: A Physician's Guide
Consumer's Guide to Radon Reduction
Technical Support Document
If you plan to make repairs yourself, be sure to contact your state radon office (see above) for a current copy of EPA's technical guidance on radon mitigation, "Application of Radon Reduction Techniques for Detached Houses. "
SURGEON GENERAL HEALTH ADVISORY:
"Indoor radon gas is a national health problem. Radon causes thousands of deaths each year. Millions of homes have elevated radon levels. Homes should be tested for radon. When elevated levels are confirmed, the problem should be corrected."
For sale by the U.S. Government Printing Office
Superintendent of Documents, Mail Stop: SSOP, Washington, DC
20402-9328
ISBN 0-16-036222-9