The following is presented as a public service by RADON.COM
You cannot see radon. And you cannot smell it or taste it. But it may be a problem in your home. That is because when you breathe air containing radon, you increase your risk of getting lung cancer. In fact, the Surgeon General 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 ration levels, your risk of lung cancer is especially high.
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 obtain the indoor radon level in a home you are
considering buying. Ask the seller for radon test results. If the home
has a radon reduction system, ask the seller for information about the
system.
If the home has not yet been tested, this Guide makes recommendations
about how to test now.
The radon testing guidelines in the "Home Buyer's and Seller's Guide to
Radon" have been developed specifically to deal with the time sensitive
nature of home purchases and sales and the potential for radon device
interference.
The guidelines in the "Home Buyer's Guide" are somewhat different from the guidelines in other EPA publications which provide radon testing and reduction information for non-real estate situations. The "Home Buyer's Guide" recommends three short-term testing options when long-term testing is not possible. The "Home Buyer's Guide" also recommends testing a home in the lowest level of the home which is currently suitable for occupancy. This is because a buyer may choose to live in a lower area of the home than that used by the seller.
Radon is a radioactive gas that has been found in homes all over the U.S.
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. Your home can trap radon inside. Sometimes radon
enters the home through well water.
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 U.S. is estimated to have elevated
radon levels. 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.
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.
If you are thinking of selling your home and you have already tested your
home for radon, provide your test results to the buyer. Review the
testing Checklist in this guide to make sure that the test was done
correctly.
No matter what kind of test you took, a potential buyer may ask for a new test especially if:
If the 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 because this may save time during real estate
transactions. You should test in the lowest level of the home which is
suitable for occupancy and finished. 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 result
of the radon test is important information about your home's radon level
that potential buyers may want to know.
You can test your own home
For low-cost do-it-yourself
radon test kits click here
or hire an EPA listed or state certified radon
tester. Call your state radon office for a list of these professional
radon testers. If you test your own home, carefully follow the Checklist
in this guide.
If you are thinking of buying a home, you may either decide to accept the
test results from the seller, ask the seller to do another test, or you
may ask for a new test to be conducted by an EPA listed or state
certified radon tester.
If you decide to accept the seller's test, make sure that the seller (or whoever took the test) followed the testing Checklist and that he or she can confirm that all the items were followed. If you plan to use the seller's test, find out as soon as possible from the seller:
If the home has not yet been tested for radon...
Make sure that a radon test is done as soon as possible. You should
consider including provisions in the contract specifying who should
conduct the test, what type of test to do, when to do the test, and how
the seller and the buyer will share the test results, test costs and, if
necessary, when radon reduction measures should be taken and who should
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 an EPA listed or state certified
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, ration tests should be taken before and after the area is finished. Radon reduction costs could be incurred if high levels are found in that area. Generally, it is less expensive to install a radon reduction system before or during renovations rather than afterwards.
Builders can incorporate radon resistant features into the homes they
build. Some states, counties and local jurisdictions may adopt radon
resistant construction features in their building codes, which builders
must then follow. Radon resistant construction standards can be applied
depending on the radon potential in a particular area. Many builders already
use radon resistant building features.
New home buyers should ask if radon resistant construction techniques
have been built into the new home they are considering for purchase.
Buyers should also ask whether information about radon is available. For
custom-built homes, the buyer should discuss radon resistant features
with the builder including the cost.
Occupants of newly constructed should have their homes tested for radon. A long-term test will provide a reading that more representative of the home's average radon level. However, short-term may be used determine if elevated radon levels exist.
Since you cannot see or smell radon, special equipment is needed to
detect it. You can buy radon devices in retail stores when you want to
test your own home, send away for radon devices from laboratories that
offer mail order services, or you can hire an EPA listed or state
certified radon tester who will test using radon devices that are
appropriate for the situation.
Preventing or Detecting Test Interference
There is a potential for test interference in real estate transactions. There are a number of ways to prevent or detect test interference such as:
Some of the most common radon testing devices are listed below. Because new testing devices may be listed by EPA or your state, 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. They include radon detectors such as charcoal canisters, alpha-track detectors, and charcoal liquid scintillation devices that are available in hardware stores, drug stores, other stores, and by mail, and electret ion chamber detectors generally only available through laboratories. They 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. Professional 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. Active radon detectors such as continuous ration monitors and continuous working level monitors require operation by trained testers. They work by continuously measuring and recording the amount of radon or its decay products in the air of the home. 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 professional tester can explain this report to you. In addition, some of these devices are specifically designed to deter and detect test interference. Currently, some of the technically advanced active devices offer the most extensive device interference features. Although these tests may cost more, they may ensure a more reliable result.
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. In addition, EPA's Radon Measurement
Protocols include technical information about the differences between
devices.
Make sure the radon device is listed by EPA's testing program or is
state-certified. The device may display the phrase "Meets EPA
Requirements" or "EPA listed." Your state radon office or a radon tester
can tell you more about radon testing devices.
Certain precautions should be followed to avoid interference during the
test period. Refer to the Checklist in this guide for more information about
how to get a reliable test.
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 if needed, radon reduction. Contact your state radon office to find out if these are available in your state.
Radon Test Device Placement
The testing device(s) should be placed in the lowest level of the home suitable for occupancy. This means testing in the lowest level currently lived in or a lower level not currently used, such as a basement, which a buyer could use for living space without renovations. The test should be in a room to be used regularly (like a living room, playroom, den or bedroom) but not a kitchen, bathroom or laundry room.
WHETHER YOU TEST FOR RADON YOURSELF OR HIRE AN EPA LISTED OR STATE CERTIFIED TESTER, ALL RADON TESTS SHOULD BE TAKEN FOR A MINIMUM OF 48 HOURS. A LONGER PERIOD OF TESTING TIME IS REQUIRED FOR SOME DEVICES.
If you are testing in a real estate transaction and you need results quickly, any of the following three ways to conduct Short-Term Tests are acceptable for determining whether the home should be fixed. Any real estate test for radon should include steps to prevent or detect device interference.
SHORT-TERM TESTING OPTIONS WHAT TO DO NEXT Passive:WHEN CHOOSING A SHORT-TERM TESTING OPTION
For info on do-it-yourself test kits... Take an initial short-term test for Fix the home if the at least 48 hours. After the first average of two tests test has been completed, take a is 4 pCi/L or more. follow-up short-term test for at least 48 hours. or Take two short-term tests at the Fix the home if the same time in the same location for average of two tests at least 48 hours. is 4 pCi/L or more. Active: Test the home with a continuous Fix the home if the monitor for at least 48 hours. average radon level is 4 pCi/L or more.
There are trade-offs among the short-term test options. One test followed by another test (sequential) would most likely give a better representation of the seasonal average. Two tests taken at the same time (simultaneous) would improve the precision of the radon test. 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 the best for you.
When you are taking a short-term test, close your windows and outside
doors and keep them closed as much as possible during the test, except
for normal entry and exit. If you are taking a short-term test lasting
less than 4 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 less than 4 days during severe storms or periods
of high winds.
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. Once you have finished the test, reseal the package and send 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.
Click here to visit The Radon Information Center---RADON.COM
EPA'S TESTING CHECKLIST
Follow this Checklist carefully so that you get the most accurate radon
test results.
Radon testing is not a complicated process, but must be done properly.
Otherwise, the test results may not be accurate and more testing may have
to be done. Disturbing or interfering with the test device or
closed-house conditions will invalidate the test results.
The seller, or an EPA listed or state certified tester, should be able to confirm that all the items in this Checklist have been followed. If the tester cannot confirm this, another test should be taken.
Before the radon testing:
During the radon test:
In many cases, home buyers and sellers may decide to have the radon test done by a professional radon tester. Make sure that the company you hire is listed in EPA's Radon Measurement Proficiency (RMP) Program or your state's certification program, if it has one.
EPA's Radon Measurement Proficiency (RMP) program is designed to help you get reliable radon tests. RMP program participants are required to show their ability to make accurate tests and follow quality assurance and EPA test guidelines. EPA issues RMP reports for your state. These reports list testing companies and individuals in your area qualified to follow EPA's residential radon testing requirements. Make sure you ask to see the professional radon tester's photo I.D. card.
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 for all homes, the radon levels in some homes today can be reduced to 2 pCi/L or below.
WHAT WILL A PROFESSIONAL RADON TESTER DO?
An EPA listed or state certified radon tester knows the proper conditions, test devices, and guidelines to get a reliable radon test. A professional radon tester can also:
RADON TEST RESULTS MEASURED IN TWO DIFFERENT UNITS
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 the 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.
Sometimes short-term tests are less definitive about whether the home is at or above 4 pCi/L. This can happen when your results are close to 4 pCi/L. For example, if the average of the 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, and you can reduce your risk of lung cancer by lowering your radon level. Read this discussion of safe and acceptable radon levels for further information.
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 in humans (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:
Additional information is available through--RADON.COM
RADON RISK IF YOU SMOKE
Radon If 1,000 people The risk of cancer WHAT TO
Level were exposed to compares to.** Stop
this level over Smoking
a lifetime... and...
20 pCi/L About 135 people <-100 times the risk Fix your
could get lung of drowning home
cancer
10 pCi/L About 71 people <-100 times the risk Fix your
could get lung of dying in a home home
cancer
8 pCi/L About 57 people Fix your
could get lung home
cancer
4 pCi/L About 29 people <-100 times the risk Fix your
could get lung of dying in an home
cancer airplane crash
Consider
fixing
between
2 and 4
pCi/L
2 pCi/L About 15 people <-2 times the risk
could get lung of dying in a car
cancer crash
1.3 pCi/L About 9 people (Average indoor (Reducing
could get lung ration level) radon
cancer levels
below 2
pCi/L is
difficult)
0.4 pCi/L About 3 people (Average outdoor
could get lung radon level)
cancer
Note: If you are a former smoker, your risk may be lower.
Radon If 1,000 people The risk of cancer WHAT TO
Level were exposed to compares to.** Stop
this level over Smoking
a lifetime... and...
20 pCi/L About 8 people <-The risk of being Fix your
could get lung killed in a violent home
cancer crime
10 pCi/L About 4 people Fix your
could get lung home
cancer
8 pCi/L About 3 people <-10 times the risk Fix your
could get lung of dying in an home
cancer airplane crash
4 pCi/L About 2 people <-The risk of drowning Fix your
could get lung home
cancer
Consider
fixing
between
2 and 4
pCi/L
2 pCi/L About 1 person <-The risk of dying
could get lung in a home fire
cancer
1.3 pCi/L Less than 1 person (Average indoor (Reducing
could get lung ration level) radon
cancer levels
below 2
pCi/L is
difficult)
0.4 pCi/L Less than 1 person (Average outdoor
could get lung radon level)
cancer
Note: If you are a former smoker, your risk may be higher.
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 preferable 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, as with any other aspect of the home purchase and sale.
The 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.
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 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 "subslab depressurization," and do not require major changes to your home. 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. The right system depends on the design of your home and other factors. As with any other household appliance, there would be costs associated with the operation of the radon reduction system.
Ways to reduce radon are discussed in EPA's "Consumer's Guide to Radon Reduction." Call your state radon office to get a copy.
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.
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 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.
WHAT SERVICES DO RADON REDUCTION CONTRACTORS PROVIDE?
Contractors who participate in EPA's RCP program are qualified to:
The Radon Information Center, presented by Air Chek, Inc.
Selecting A Radon Reduction Contractor
You should use a radon reduction contractor who is listed by EPA's Radon Contractor Proficiency (RCP) Program. This Program tests the technical knowledge of contractors to ensure that hey can correct radon problems. RCP contractors must follow specific guidelines which make certain that their work meets minimum quality standards. RCP contractors carry photo I.D. cards and are listed in RCP Program reports.
Radon reduction contractors are required to take the RCP exam and then follow the RCP Mitigation Standards. These standards are available from your state radon office. The RCP radon reduction contractor is also required to review radon measurement results before beginning radon reduction work.
In addition, the RCP contractor must recommend that the home be tested again by an independent EPA listed or state certified radon tester after completing radon reduction work to confirm that elevated levels have been reduced.
RADON IN WATER
Compared to radon entering the home through soft, radon entering the home through water in most cases will 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, radon has been found in well water. If you have tested the air in your home and found a radon problem, and your water comes from a well, have the water tested. If you are on a public water supply and are concerned that radon may be entering your home through the water, call your public water supplier. The testing device and procedures used to find out the radon levels of your home's water supply are different from the device and procedures used to test your home's indoor air levels for radon.
Radon problems in water can be readly 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. Point-of-use devices usually only treat a small portion of your water and are not effective in reducing radon risk in water.
Call your State radon office for a copy of the "Consumer's Guide to Radon Reduction" or call EPA's Drinking Water Hotline (1 800 426-4791) for more information on radon in water.
SHOULD YOUR RADON TESTER ALSO BE YOUR RADON REDUCTION CONTRACTOR?
Be aware that there is a potential conflict of interest if you use the same company to conduct both the test and the radon reduction of the home. If the same radon testing professional also offers to do radon reduction of the home, make sure that the testing is done according to the Testing Checklist.
EPA's Radon Proficiency Programs (RMP and RCP) work together to protect home buyers and sellers. Make sure you only hire professional testers and radon reduction contractors who are EPA qualified or state certified. Always ask to see the contractor's I.D. card.
You should also consider getting more than one cost estimate and asking for references from radon testing and radon reduction companies in your area.
Some states have additional certification requirements, and may require the homeowner to sign a waiver if one firm conducts both testing and radon reduction. Contact your state radon office for more information.
FACT: Although some scientists dispute the precise number of deaths due to radon, the major health organizations (like the Centers for Disease Control, 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 devices are not reliable and are difficult to find.
FACT: Radon testing can be conducted by professionally trained RMP listed or state certified radon tester.
Active radon devices can continuously gather and periodically record radon levels reveal any unusual swings in the radon level during the test.
Reliable testing devices are also available through the mail, in hardware stores and other retail outlets. Call your state radon office for a list of radon device companies that have met EPA requirements for reliability or are state certified.
MYTH: Radon testing is difficult and time-consuming.
FACT: Radon testing is easy. You can test your own home or you can hire an EPA listed or state certified radon tester. Either approach takes only a small amount of the homeowner's time or effort.
MYTH: Homes with radon problems cannot be fixed.
FACT: There are solutions to radon problems in homes. Thousands of home owners have already lowered elevated radon levels in their homes. Radon levels can be readily lowered for $500 to $2,500. Call your state radon office for a list of contractors that have met EPA requirements or are state certified.
MYTH: Radon only affects certain types of homes.
FACT: Radon can be a problem in all types of homes such as old homes, new homes, drafty homes, insulated homes, homes with basements and homes without basements. Construction materials and the way the home has been built may also affect radon levels.
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 the home's radon level is to test.
MYTH: A neighbor's test result is a indication of whether your home has a radon problem.
FACT: It is 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 his or her water for radon.
FACT: While radon gets into some homes through the water, it is important to first the air in the home for radon. If high radon levels are found and the home has a well, call the Safe Drinking Water Hotline at 1 800-426. 4791, or your state radon office for more information.
MYTH: It is difficult to sell a home where radon problems have been discovered.
FACT: Where radon problems have been fixed, home sales have not been blocked. The added protection could be a good selling point.
MYTH: I have lived in my home for so long, it does not make sense to take action now.
FACT: You will reduce your risk of lung cancer when you reduce radon levels, even if you have lived with a radon problem for a long time.
MYTH: Short-term tests cannot be used for making a decision about whether to reduce the home's high radon levels.
FACT: Short-term tests may be used to decide whether to reduce the home's high radon levels. However, the closer the short-term testing result is to 4 pCi/L, the less certainty there is about whether the home's year-round average is above or below that level. Keep in mind that radon levels below 4 pCi/L still pose some risk and that radon levels can be reduced in some homes to 2 pCi/L or below.
For more info go to THE RADON INFORMATION CENTER
Or:
Ask your state radon office to send you these free guides:
Contact the EPA's Drinking Water Hotline (1 800 426-4791) for information on radon in water.
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."
Consumers need to know about the health of a house they are considering
purchasing, including whether there is a radon problem, and if so, how to
fix it. The Home Buyer's and Seller's Guide to Radon provides practical
consumer information that every home buyer needs to know.
THE RADON INFORMATION CENTER maintains many radon links, facts,
frequently asked questions, and the lowest price test kits available on the web.
INTRODUCTION:
A Physician's Guide To Radon
This booklet on radon has been developed for physicians by the U. S. Environmental Protection Agency in consultation with the American Medical Association (AMA). Its purpose is to enlist physicians in the national effort to inform the American public about the serious health risk posed by indoor radon gas.
Lung cancer's very high associated mortality rate is even more tragic because a significant portion of lung cancer is preventable. While smoking remains the number one cause of lung cancer, radon presents a significant second risk factor. That is why, in addition to encouraging patients to stop smoking, it is important for physicians to inquire about and encourage patients to test for radon levels in their homes. One way to do this is for physicians to join those health care professionals and organizations who have begun to include questions about the radon level in patients' homes on standardized patient history forms.
Because the public views physicians as advisors on health and prevention of disease, physicians are in a unique position to play a vital role in informing the public about the common and serious risk of radon, and in educating their patients in testing procedures and remediation methods for correcting elevated indoor radon levels, thereby helping to reduce the number of lung cancer deaths.
Free radon information materials (posters, pamphlets, videos) are available from your state radon office (see State Radon Contacts list towards end of this brochure) to assist you in educating your patients about radon.
TABLE OF CONTENTS:
What is Radon?
Characteristics and Source of Radon
The Health Risk
How does Radon Induce cancer?
What is the Evidence?
Is Occupational Exposure to Radon Comparable to Residential Exposure?
What About Smoking and Radon Exposure?
The Solution
Why Should Every Home be Tested?
How Do You Obtain a Reliable Test Result?
Radon Testing Methods
Radon Test Devices
How to Test
Interpreting Radon Test Results
Basis for the 4 pCi/L Radon "Action Level"
Radon Reduction Methods
Other Indoor Air Pollutants
Environmental Tobacco Smoke (ETS)
Biological Air Pollutants
Volatile Organic Compounds (VOCs)
Other Combustion Products
Most Commonly Asked Questions about Radon
State Radon Contacts
Additional Information Sources and Suggested Reading List
According to the Office of the Surgeon General: Indoor radon gas is a serious health problem in our nation that can be addressed by individual action. Unless people become aware of the danger radon poses, they will not act. Millions of homes are estimated to have elevated radon levels. Fortunately, the solution to this problem is straight-forward. Like the hazards from smoking, the health risks of radon can be reduced.
Click here to go to: RADON.COM
Radon Causes Thousands Of Preventable Lung Cancer Deaths Each Year
Each year in the United States exposure to indoor radon gas causes thousands of preventable lung cancer deaths. In fact, the Surgeon General has warned that radon is the second leading cause of lung cancer in the United States. Extensive epidemiological evidence from studies of underground miners, complemented by animal data, indicates that radon causes lung cancer in both smokers and nonsmokers, although malignancy is especially likely to occur in cigarette smokers. Exposure to both smoking and radon greatly enhances the risk of lung cancer. The carcinogenicity of radon is supported by a consensus of opinion among national and international health organizations. By informing patients about the health risk posed by radon exposure and providing practical advice about radon testing and mitigation, physicians can have a tremendous positive impact on the national effort to prevent radon-induced lung cancer.
*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 the 1990 National Safety Council reports.
Radon Is Easy To Detect And Reduce In A Home
The danger posed by radon can be detected rather easily through inexpensive do-it yourself testing, or through a trained radon contractor. Radon test kits can be purchased by mail order or in hardware stores and other retail outlets. Because of the serious health risk posed by radon, the U. S. Environmental Protection Agency (EPA) recommends that all homes be tested for radon below the third floor.
If an elevated radon level is discovered in a home, it can be corrected. It is recommended that a confirmed radon level of 4 picocuries per liter (pCi/L) of air or higher be reduced to decrease the risk of developing lung cancer. The cost of radon mitigation in a typical home ranges from about $500 to about $2,500. Your state radon information office (see page toward end of this brochure) can provide general advice about radon testing and mitigation, as well as specific information about qualified radon contractors in your state.
"Physicians are often the only science professional known to their patients and are almost always a trusted source of information about science in general and health in particular. Radon does increase the risk of lung cancer, and physicians have an obligation to educate their patients about the health risk associated with radon."
(Jerod M. Loeb, Assistant Vice-President for Science, Technology and Public Health of the American Medical Association)
WHAT IS RADON?:
Radon-222 is a radioactive gas released during the natural decay of thorium and uranium, which are common, naturally occurring elements found in varying amounts in rock and soil. Odorless, invisible, and without taste, radon cannot be detected with the human senses.
Radon-222 decays into radioactive elements, two of which -- polonium-218 and polonium-214 -- emit alpha particles, which are highly effective in damaging lung tissues. These alpha-emitting radon decay products have been implicated in a causal relationship with lung cancer in humans.
CHARACTERISTICS AND SOURCES OF RADON:
Outdoors, where it is diluted to low concentrations in the air, radon poses significantly less risk than indoors. In the indoor air environment, however, radon can accumulate to significant levels. The magnitude of radon concentration indoors depends primarily on a building's construction and the amount of radon in the underlying soil. The soil composition under and around a house affects radon levels and the ease with which radon migrates toward a house. Normal pressure differences between the house and the soil can create a slight vacuum in the home that can draw radon gas from the soil into the building.
Radon gas can enter a home from the soil through cracks in concrete floors and walls, floor drains, sump pumps, construction joints, and tiny cracks or pores in hollow-block walls. Radon levels are generally highest in basements and ground floor rooms that are in contact with the soil. Factors such as the design, construction, and ventilation of the home affect the pathways and sources that can draw radon indoors. Another source of radon indoors may be air released by well water during showering and other household activities. Compared to radon entering the home through soil, radon entering the home through water will in most cases be a small source of risk.
HOW RADON ENTERS YOUR HOUSE:
THE HEALTH RISK:
How Does Radon Induce Cancer?
If inhaled, radon decay products (polonium-218 and polonium-214, solid form), unattached or attached to the surface of aerosols, dusts, and smoke particles, become deeply lodged or trapped in the lungs, where they can radiate and penetrate the cells of mucous membranes, bronchi, and other pulmonary tissues. The ionizing radiation energy affecting the bronchial epithelial cells is believed to initiate
the process of carcinogenesis. Although radon-related lung cancers are mainly seen in the upper airways, radon increases the incidence of all histological types of lung cancer, including small cell carcinoma, adenocarcinoma, and squamous cell carcinoma. Lung cancer due to inhalation of radon decay products constitutes the only known risk associated with radon. In studies done on miners, variables such as age, duration of exposure, time since initiation of exposure and especially the use of tobacco have been found to influence individual risk. In fact, the use of tobacco multiplies the risk of radon-induced lung cancer enormously.
What is the Evidence?
More is known about the health risk of radon exposure to humans than about most other human carcinogens. This knowledge is based on extensive epidemiological studies of thousands of underground miners, carried out over more than fifty (50) years world-wide, including miners in the United States and Canada. In addition to the miner data, experimental exposures of animals confirm that radon and its decay products can cause lung cancer.
The research on lung cancer mortality in miners exposed to radon progeny is substantial and consistent. Studies of thousands of miners, some with follow-up periods of thirty (30) years and more, have been conducted in metal, fluorspar, shale, and uranium mines in the United States, Canada, Australia, China, and Europe. These studies have consistently shown an increase in lung cancer occurrence with exposure to radon decay products, despite differences in study populations and methodologies.
The miner studies produced some interesting findings.
The following table lists seven (7) of the major epidemiological studies of underground miners and their reported relative risk coefficients.
ESTIMATES OF LUNG CANCER RISK FROM EPIDEMIOLOGICAL STUDIES OF UNDERGROUND MINERS EXPOSED TO RADON:
Czech Uranium Miners -
Average Exposure (WLM)a = 313
Relative Risk Coefficient (%/WLM)b = 1.92
References = Thomas et al, 1985
Average Exposure (WLM)a = 226
Relative Risk Coefficient (%/WLM)b = 1.5
References = Sevc et al, 1988
Ontario Uranium Miners -
Average Exposure (WLM)a = 40-90
Relative Risk Coefficient (%/WLM)b = 0.5-1.3
References = Muller, 1984
Average Exposure (WLM)a = 40-90
Relative Risk Coefficient (%/WLM)b = 1.4c
References = NAS, 1988
New Mexico Uranium Miners -
Average Exposure (WLM)a = 111.4
Relative Risk Coefficient (%/WLM)b = 1.8
References = Samet et al, 1991
Swedish Iron Miners -
Average Exposure (WLM)a = 81.4
(Malmberget) Relative Risk Coefficient (%/WLM)b = 3.6
References = Radford & St. Clair Renard, 1984
Average Exposure (WLM)a = 81.4
Relative Risk Coefficient (%/WLM)b = 1.4c
References = NAS, 1988
Colorado Plateau -
Average Exposure (WLM)a = 834
Uranium Miners Relative Risk Coefficient (%/WLM)b =.45
References = Thomas et al, 1988
Average Exposure (WLM)a = 834
Relative Risk Coefficient (%/WLM)b = .06c
References = NAS, 1988
Eldorado (Beaverlodge) -
Average Exposure (WLM)a = 20.2
Uranium Miners Relative Risk Coefficient (%/WLM)b = 3 References
= Howe et al, 1986
Average Exposure (WLM)a = 20.2
Relative Risk Coefficient (%/WLM)b = 2.6c
References = NAS, 1988
Newfoundland Fluorospar -
Average Exposure (WLM)a = 382.2
Miners Relative Risk Coefficient (%/WLM)b = 0.9
References = Morrison et al, 1988
a = Working level month (WLM) is the cumulative exposure equivalent to one (1) working level (WL) for a working month (170 hours). A WL is any combination of short-lived radon daughters in one (1) liter of air that will result in the emission of 1.3 x 105 MeV of potential alpha energy. A home exposure of 4 pCi/L for seventy (70) years would approximately equal a cumulative exposure of 54 WLM (assuming 75% occupancy).
b = The relative risk coefficient is the fractional increase above the baseline lung cancer incidence or mortality rate per WLM. For example, the Czech Uranium Miner demonstrated a 1.92% increased lung cancer risk for every WLM of exposure. Exposure to five (5) WLM would therefore increase lung cancer risk by 9.6% over baseline.
c = Estimate based on reanalysis of the data by the NAS with the cooperation of the principal investigators.
*The excess relative risk coefficient used in EPA's risk assessment (1.3%/WLM) is that derived by the NAS BEIR IV report based on their analysis of studies of underground mines.
A detailed discussion of the strengths and weaknesses of the various miner studies can be found in the EPA's Technical Support document for the 1992 Citizen's Guide to Radon, available from your state radon office, or the BEIR IV Report (National Academy of Sciences (NAS) 1988).
Animal experiments conducted in the United States and France also have confirmed the carcinogenicity of radon and have provided insight into the nature of the exposure-response relationship, as well as the modifying effects of the exposure rate. To date these animal studies have produced several relevant findings.
In 1988, a panel of world experts convened by the World Health Organization's International Agency for Research on Cancer unanimously agreed that there is sufficient evidence to conclude that radon causes cancer in humans and in laboratory animals (IARC, 1988). Scientific committees assembled by the National Academy of Sciences (NAS, 1988), the International Commission on Radiological Protection (ICRP, 1987), and the National Council on Radiation Protection and Measurement (NCRP, 1984) also have reviewed the available data and agreed that radon exposure causes human lung cancer.
Recognizing that radon is a significant public health risk, scientific and professional organizations such as the American Medical Association, the American Lung Association, and the National Medical Association have developed programs to reduce the health risks of radon. The National Institute for Occupational Safety and Health (NIOSH) reviewed the epidemiological data and recommended that the annual radon progeny exposure limit for the mining industry be lowered (NIOSH 1987).
Is Occupational Exposure to Radon Comparable to Residential Exposure?
Because questions have been raised about the appropriateness of using the epidemiological studies of underground miners as a basis for estimating the risk radon poses to the general population, the EPA commissioned the National Academy of Sciences (NAS) to investigate the difference between underground miners and members of the general public in the doses they receive per unit exposure due to inhaled radon progeny.
The NAS report, published in 1991 (National Academy of Sciences, 1991, Comparative Dosimetry of Radon in Mines and Homes. National Academy Press, Washington, D.C.), concluded that it is reasonable to extrapolate from the miner data to a residential situation, but that the effective doses per unit of exposure for people in their homes is approximately thirty percent (30%) less than for the miners. In its analysis, NAS considered variables such as the amount and type of dust to which the radon decay particles would attach, the breathing rate of working miners compared to that of people at home, and the presence of women and children in the homes.
EPA has adjusted its residential risk estimates accordingly. The result is still considerable--EPA now estimates that approximately 14,000 lung cancer deaths in the United States per year are due to residential radon exposures, with an uncertainty range of 7,000 to 30,000. As more data are gathered about residential radon exposures, the risk estimates may be adjusted further. Enough data exists now, however, to be able to say with certainty that thousands of preventable lung cancer deaths annually in the United States are attributable to indoor residential exposure to radon.
Presented by The Radon Information Center---RADON.COMMore information about residential exposure to radon is needed to answer important questions about radon's effect on women and children--groups not included in the occupational studies of miners. Although children have been reported to be at greater risk than adults of developing certain types of cancer from radiation, currently there is no conclusive evidence that radon exposure places children at any greater risk. Some miner studies and animal studies indicate that for the same total exposure, a lower exposure over a longer time is more hazardous than short, high exposures. These findings increase concerns about residential radon exposures. Epidemiological case control studies are underway in the U.S. and Europe, the pooled results of which should enhance the understanding of the risk of residential exposure to radon.
What About Smoking and Radon Exposure?
Some people ask whether the lung cancer deaths attributed to radon exposure actually may be the result of smoking. A 1989 study by researchers from the National Institute for Occupational Safety and Health, the Centers for Disease Control, the Harvard School of Public Health, and the University of California at Davis demonstrated a greatly incased lung cancer risk in nonsmoking uranium miners exposed to high radon concentrations: compared to typical non-smoking populations, these miners had nine (9) to twelve (12) times the risk of developing lung cancer (Roscoe et al, JAMA 262(5): 629-633, 1989).
Evidence from some of the epidemiological studies of underground miners, primarily U. S. uranium miners, indicate that radon exposure and smoking may have a synergistic relationship. Either smoking or radon exposure can independently increase the risk of lung cancer; however, exposure to both greatly enhances that risk.
RADON RISK COMPARISON FOR SMOKERS AND NONSMOKERS:
* Bq/m3 = Bequerel/meter3
THE SOLUTION:
Why Should Every Home be Tested?
The EPA and the U. S. Surgeon General recommend testing all homes below the third floor for radon. Data gathered by the EPA national radon survey indicate that elevated radon levels are present in about six million (6,000,000) homes throughout the United States. In every state there are homes with dangerously high radon levels. Because the radon concentration inside a home is due to factors relating to its structure and geographic location, each individual home must be tested to determine its radon level. Two adjacent houses may have radically different radon levels. And any kind of home can have elevated levels -- new or old, drafty or well-sealed, and basement or non-basement.
How do You Obtain a Reliable Test Result?
Although radon cannot be seen or smelled, with the proper equipment its presence is relatively easy to detect.
The EPA operates a voluntary Radon Measurement Proficiency (RMP) Program that evaluates radon measurement companies and the test services they offer. EPA recommends that testing services be purchased from one of the organizations listed by EPA or certified by the state. Most companies indicate U. S. EPA or RMP approval on the test kit box by displaying the phrase, "Meets EPA Requirements." A list of radon measurement companies and individuals the EPA has determined to be "proficient" can be obtained from the State Radon Office (see list towards the end of this brochure). A test kit obtained from a qualified company, if used according to directions, should provide accurate results.
Radon Testing Methods
The quickest way to test for radon is with a short-term "do-it- yourself" radon test kit, available by mail order and in many retail outlets or by hiring an EPA qualified or state-certified radon tester. Common short-term test devices are charcoal canisters, alpha track detectors, liquid scintillation detectors, electret ion chambers, and continuous monitors. A short-term testing device remains in the home for two (2) to ninety (90) days, depending on the type of device. Because radon levels tend to vary from day-to-day and season-to-season, a long-term test is more likely than a short-term test to measure the home's year-round average radon level. If results are needed quickly, however, a short-term test followed by a second short-term test may be used to determine the severity of the radon problem.
Long-term test devices, comparable in cost to devices for short-term testing, remain in the home for more than three (3) months. A long-term test is more likely to indicate the home's year-round average radon level than a short-term test. Alpha track detectors and electret ion detectors are the most common long-term test devices.
Radon Test Devices
Charcoal canister and liquid scintillation detectors contain small quantities of activated charcoal. Radon and its decay products are absorbed onto the charcoal and are measured by counting with a sodium iodide detector or a liquid scintillation counter.
Alpha track detectors contain a small sheet of plastic that is exposed for a period of one (1) to three (3) months. Alpha particles etch the plastic as they strike it. These marks are then chemically treated and counted in the laboratory to determine the radon concentration.
Electret ion detectors contain an electrostatically charged Teflon disk. Ions generated by the decay of radon strike and reduce the surface voltage of the disk. By measuring the voltage reduction, the radon concentration can be calculated.
Continuous monitors are active devices which need power to function. They require operation by trained testers and work by continuously measuring and recording the amount of radon in the home.
How To Test
During a short-term test, doors and windows are closed twelve (12) hours prior to testing and throughout the testing period. (A short-term test lasting two (2) or three (3) days should not be conducted during unusually severe storms or periods of unusually high winds.) The test kit is placed in the lowest lived-in level of the home, at least twenty (20) inches above the floor, in a room that is used regularly, but not in the kitchen or bathroom where high humidity or the operation of an exhaust fan could affect the validity of the test. At the end of the test period, the kit is mailed to a laboratory for analysis; results are mailed back in a few weeks.
In some cases, such as real estate transactions, trained EPA-listed or state-certified contractors conduct the radon test. The EPA's pamphlet Home Buyer's and Seller's Guide to Radon, which addresses issues during real estate transactions, is available from state radon offices.
INTERPRETING RADON TEST RESULTS:
A. If the short-term test result is 4 pCi/L or higher, conduct a follow-up test to confirm the results.
B. Follow-up with either a long-term test or a second short-term test.
For a better understanding of the home's year-round average radon level, take a long-term test.
If results are needed quickly, take a second short-term test.
The higher the initial short-term result, the more certain the homeowner can be to conduct a short-term rather than a long-term follow-up test.
If the first short-term test result is several times the action level--
for example, about 10 pCi/L or higher -- a second short-term test should be taken immediately.
C. If the long-term follow-up test result is 4 pCi/L or more, fix the home.
If the homeowner followed up with a second short-term test: the higher the short-term results, the more certain the homeowner can be that the home should be fixed. The homeowner should consider fixing the home if the average of the first and second test is 4 pCi/L or higher.
Basis for the 4 pCi/L Radon "Action Level"
No radon level is considered "safe". The risk of developing lung cancer is directly proportional to the levels and duration of exposure to radon: the higher the radon concentration, the higher the lung cancer risk. The 4 pCi/L "Action Level" is based on current mitigation technology. Today, mitigation technology can almost always reduce high radon concentration levels to below 4 pCi/l and to 2 pCi/L or below 70-80 percent of the time. The average radon level in homes is about 1.25 pCi/L. Although Congress passed legislation in 1988 establishing a national goal that indoor radon levels not exceed ambient outdoor radon levels (0.2-0.7 pCi/L), this goal is not yet technologically achievable.
Radon Reduction Methods
Radon in soil is drawn indoors by the differential between the relatively low air pressure in the house and the higher air pressure in the soil. Therefore, radon reduction strategies fall into two basic categories: those that prevent the entry of radon gas into the home, and those that attempt to remove the radon once it has entered the home. In most situations, the first approach -- preventing radon entry -- is the most effective.
Although sealing cracks and other openings in the foundation is a basic part of most approaches to radon reduction, sealing alone is not recommended; it is best done in conjunction with other mitigation techniques to enhance their effectiveness.
The most popular radon mitigation technology is called "sub-slab depressurization" or "sub-slab suction." The "sub-slab depressurization" technique removes radon-laden air from beneath the foundation and vents it outside the house by installing a fan and inserting a pipe through the foundation into the aggregate below, running it to a point outside the shell of the house. A similar technique, "sub-membrane depressurization," which is effective in buildings with earth-floored crawlspaces or basements, uses a plastic barrier over the soil as a collection cover. Another depressurization technique for preventing radon entry, "blockwall depressurization," uses a fan and duct work to draw suction on the hollow interior cavities of a concrete block wall. By keeping the air pressure within the block wall lower than the air pressure in the basement, the soil gas is removed before it can enter the basement.
Reducing radon levels requires technical knowledge and special skills. The EPA operates a Radon Contractor Proficiency (RCP) Program that evaluates radon reduction contractors. As with the Radon Measurement Proficiency (RMP) Program, the EPA sends a list of RCP contractors to state radon offices (see list near the end of this brochure). Selecting a radon contractor is much like choosing a contractor for other home repairs; it makes sense to get references and more than one estimate. The average cost to correct a radon problem in a home is about $1,200, although it can range from about $500 to about $2,500. A free copy of A Consumer's Guide to Radon Reduction is available from state radon offices. People who choose to fix their homes themselves should refer to the EPA's technical guide, Radon Reduction Techniques for Detached Houses, available from state radon offices.
After the radon reduction procedure is complete, the home should be retested. Most radon reduction systems include a monitor that will alert the homeowner if the system needs servicing.
OTHER INDOOR AIR POLLUTANTS:
PREVENTIVE MEASURES THAT CAN BE TAKEN TO REDUCE YOUR EXPOSURE TO INDOOR AIR POLLUTANTS INCLUDE THE FOLLOWING:
Environmental Tobacco Smoke (ETS):
Biological Air Pollutants:
Volatile Organic Compounds (VOCs):
Other Combustion Products:
Environmental Tobacco Smoke (ETS)
The U. S. Environmental Protection Agency has classified environmental tobacco smoke (ETS) as a Group A (known human) carcinogen. EPA estimates that approximately 3,000 lung cancer deaths in the United States per year among nonsmokers are due to ETS. The U. S. Surgeon General, the National Research Council, and the National Institute for Occupational Safety and Health have all concluded that passive smoking can cause lung cancer in otherwise healthy adults who never smoked.
Children's lungs are even more susceptible to harmful effects from ETS. In infants and young children up to three years, exposure to ETS causes an approximate doubling in the incidence of pneumonia, bronchitis, and bronchiolitis. There is also strong evidence of increased middle ear effusion and reduced lung function and lung growth. Several recent studies link ETS with increased incidence and prevalence of asthma and increased severity of asthmatic symptoms in children of mothers who smoke heavily.
Environmental tobacco smoke is a complex mixture of more than 4,000 chemicals found in both vapor and particle phases, many known toxic and carcinogenic agents. ETS consists of both "sidestream" smoke, the emission from the burning end of the cigarette, and exhaled "mainstream smoke," the smoke inhaled by the active smoker.
Biological Air Pollutants
Dust mites, molds, animal dander, and other biologicals are found in some degree in every home and workplace. High relative humidity is the primary factor encouraging biological agents to grow and be released into the air. Biological agents are known to cause three types of human diseases: infections, where pathogens invade human tissues; hypersensitivity diseases, where specific activation of the immune system causes disease; and toxicoses, where biologically produced chemical toxins cause direct toxic effects.
Volatile Organic Compounds (VOCs)
Volatile Organic Compounds (VOCs) are emitted as vapors or gases at ordinary temperatures from a variety of sources. Many are toxic, including benzene, carbon tetrachloride, and formaldehyde. VOCs can be found in paint, upholstery, spray cans, copy machine toners, clothing, and other sources. Health effects range from irritation of the eyes and respiratory system to kidney or liver damage, cancer, or birth defects.
Other Combustion Products
Aside from ETS, the major combustion pollutants -- carbon monoxide (CO), nitrogen dioxide (NO2), and sulfur dioxide (SO2) -- that may be present at harmful levels in the home or workplace stem chiefly from malfunctioning or misusing heating devices. An additional source of exposure may be motor vehicle emissions as a result of a garage or loading dock located near air intake vents. Symptoms may mimic influenza and include fatigue, nausea, dizziness, headaches, cognitive impairment, and tachycardia during the heating season.
For more information on these and other indoor air pollutants, call EPA's Indoor Air Quality Information Clearinghouse (1-800-438-4318) for Indoor Air Pollution: An Introduction for Health Professionals and The Inside Story: A Guide to Indoor Air Quality.
MOST COMMONLY ASKED QUESTIONS ABOUT RADON:
Q. Where does radon come from?
A. Radon is a naturally occurring gas that results from the breakdown of uranium commonly found in soil.
Q. How does radon enter my home?
A. Radon comes up through the soil and rocks surrounding your home and seeps through cracks in concrete walls and floors, floor drains, sump pumps, joints, and hollow-brick walls.
Q. Why haven't I heard of the radon danger until recently?
A. Radon has always existed. However, it was not until the 1980s that dangerous radon levels were found inside homes across the U. S.
Q. What are the health risks?
A. Radon is the second leading cause of lung cancer.
Q. How do I know if I have radon in my home?
A. By testing with an EPA-listed or State-certified easy-to-use, inexpensive test kit as soon as possible, or by hiring an EPA-listed or State-certified contractor to test your home for you.
Q. If I have a radon problem, can it be corrected?
A. Yes. The use of trained personnel is recommended. State radon offices can recommend qualified contractors. In some cases, the problem can be treated by the homeowners if they have experience with other kinds of home repair.
Q. Will my neighbor's radon measurement indicate whether or not I have a radon problem?
A. No. Radon levels vary from house to house. The only way to know if you have a radon problem is to conduct a test.
Q. How can I get a reliable radon test kit?
A. Kits can be purchased through the mail. Look for a test kit from a company that is State-certified or EPA-listed.
NATIONAL RADON HOTLINE: 1 800/SOS-RADON
ADDITIONAL INFORMATION SOURCES AND SUGGESTED READING LIST:
The following free materials are available from your state radon office:
Reducing Radon Risk
A Citizen's Guide to Radon (1992 Edition): The Guide to Protecting Yourself and Your Family from Radon (available in Spanish)
Technical Support Document for the 1992 Citizen's Guide to Radon
Home Buyer's and Seller's Guide to Radon
Radon in Schools
Consumer's Guide to Radon Reduction
For additional indoor air publications, call EPA's Indoor Air Quality Information Clearinghouse (1-800-438-4318).
The Inside Story: A Guide to Indoor Air Quality
Indoor Air Pollution: An Introduction for Health Professionals
Secondhand Smoke
Your state radon office has other promotional materials, including free posters, to display in your office.
Suggested Reading List:
Council on Scientific Affairs. 1987. American Medical Association (AMA), Radon in Homes. Journal of the American Medical Association. 258:668-672.
Council on Scientific Affairs. 1991. Health Effects of Radon Exposure. Archives of Internal Medicine. 151:674-677.
Lubin, J.M., Samet and Weinberg, C. 1990. Design Issues in Epidemiologic studies of Indoor Exposure to Rn and Risk of Lung Cancer. Health Physics. 59(6): 807-817.
National Academy of Sciences, 1991. Comparative Dosimetry of Radon in Mines and Homes. National Academy Press, Washington, DC.
National Academy of Sciences, 1988. Health Risk of Radon and Other Internally Deposited Alpha Emitters; BEIR IV. National Academy press, Washington, DC.
Roscoe, R.J., et al. 1989. Lung Cancer Mortality Among Non-Smoking Uranium Miners Exposed to Radon Daughters. Journal of the American Medical Association.
262(5): 629-633.
Samet, J.M., Stolwijk, J. and Rose, S. 1991a. Summary: International Workshop on Residential Rn Epidemiology. Health Physics. 60(2):223-227.
Samet, J.M. and Hornung, R. 1990. Workshop on Indoor Air Quality: Review of radon and Lung Cancer Risk. Risk Analysis. 10(1): 65-75.
U.S. DOE/Office of Energy Research, 1989. International Workshop on Residential Radon Epidemiology: Workshop Proceedings. Commission of European Communities, Radiation Protection Program. CONF-8907178.