How does radon get into your home?
Any home may have a radon problem.
Radon is a radioactive gas. It 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
Reduce Radon Levels in Your Home
Radon is the leading cause of lung cancer for non-smokers and the second leading cause of lung cancer in the general population. The Surgeon General and EPA recommend testing for radon and reducing radon in homes that have high levels. Fix your home if your radon level is confirmed to be 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. If you smoke and your home has high radon levels, your risk of lung cancer is especially high.
Indoor Environments Division (6609J)
EPA 402K-10/005 September, 2010
How to Order Publications
You can order Indoor Air Quality publications from EPA’s National Service Center for Environmental Publications (NSCEP)
P.O. Box 42419,
Cincinnati, OH 45242-0419
Website: www.epa.gov/nscep
Phone: 1-800-490-9198 (M-F from 9:30-5:30 eastern)
Fax: (301) 604-3408
E-mail: nscep@bps-lmit.com
Select A State Certified and/or Qualified Radon Mitigation Contractor
Choose a qualified radon mitigation contractor to fix your home. Start by checking with your state radon office. Many states require radon professionals to be licensed, certified, or registered. You can also contact private radon proficiency programs for lists of privately certified radon professionals in your area. See State Radon Contacts (click on your state for contacts and resources).
Radon Reduction Techniques Work
Radon reduction systems work. Some radon reduction systems can reduce radon levels in your home by up to 99 percent. Most homes can be fixed for about the same cost as other common home repairs. Your costs may vary depending on the size and design of your home and which radon reduction methods are needed. Get an estimate from one or more qualified radon mitigation contractors. Hundreds of thousands of people have reduced radon levels in their homes.
Maintain Your Radon Reduction System
Maintaining your radon reduction system takes little effort and keeps the system working properly and radon levels low. See Maintaining Your Radon Reduction System.
Introduction
You have tested your home for radon, but now what? This booklet is for people who have tested their home for radon and confirmed that they have elevated radon levels — 4 pCi/L or higher. This booklet can help you:
- Select a qualified radon mitigation contractor to reduce the radon levels in your home.
- Determine an appropriate radon reduction method.
- Maintain your radon reduction system.
If you want information on how to test your home for radon, call your state radon office. You can also read A Citizen’s Guide to Radon or, if testing during a home sale, read the Home Buyer’s and Seller’s Guide to Radon.
How Radon Enters Your Home
Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil, rock, and water. Air pressure inside your home is usually lower than pressure in the soil around your home’s foundation. Because of this difference in pressure, your home acts like a vacuum, drawing radon in through foundation cracks and other openings.
Radon also may be present in well water and can be released into the air in your home when water is used for showering and other household uses. In most cases, radon entering the home through water is a small risk compared with radon entering your home from the soil. In a small number of homes, the building materials — such as granite and certain concrete products — can give off radon, although building materials rarely cause radon problems by themselves. In the United States, radon gas in soils is the principal source of elevated radon levels in homes.
Radon is a Cancer-causing, Radioactive Gas
Radon is estimated to cause many tens of thousands of lung cancer deaths each year. In fact, the Surgeon General has warned that radon is the second leading cause of lung cancer in the United States. 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.
What Do Your Radon Test Results Mean?
Selecting a Radon Test Kit
Since you can’t see or smell radon, special equipment is needed to detect it. When you’re ready to test your home, contact your state radon office for information on locating qualified test kits or qualified radon testers. You can also order test kits and obtain information from www.sosradon.org . There are two types of radon testing devices. Passive radon testing devices do not need power to function. These include charcoal canisters, alpha-track detectors, charcoal liquid scintillation devices, and electric ion chamber detectors. Both short- and long-term passive devices are generally inexpensive. Active radon testing devices require power to function and usually provide hourly readings and an average result for the test period. These include continuous radon monitors and continuous working level monitors, and these test may cost more. A state or local official can explain the differences between the devices and recommend ones that are most appropriate for your needs and expected testing conditions. Make sure to use a radon testing devices from a qualified laboratory.
Any radon exposure has some risk of causing lung cancer. The lower the radon level in your home, the lower your family’s risk of lung cancer. The amount of radon in the air is measured in pCi/L.
The U.S. Congress has set a long-term goal that indoor radon levels be no more than outdoor levels; about 0.4 pCi/L of radon is normally found in the outside air. EPA recommends fixing your home if the results one long-term test or the average of two short-term tests show radon levels of 4 pCi/L or higher. With today’s technology, radon levels in most homes can be reduced to 2 pCi/L or below. You may also want to consider fixing if the level is between 2 and 4 pCi/L.
A short-term test remains in your home for two days to 90 days, whereas a long-term test remains in your home for more than 90 days. All radon tests should be taken for a minimum of 48 hours. A short-term test will yield faster results, but a long-term test will give a better understanding of your home’s year-round average radon level.
The EPA recommends two categories of radon testing. One category is for concerned homeowners or occupants whose home is not for sale; refer to EPA’s “A Citizen’s Guide to Radon” for testing guidance. The second category is for real estate transactions; refer to EPA’s “Home Buyer’s and Seller’s Guide to Radon,” which provides guidance and answers to some common questions.
Why Hire a Contractor?
EPA recommends that you have a qualified radon mitigation contractor fix your home because lowering high radon levels requires specific technical knowledge and special skills. Without the proper equipment or technical knowledge, you could actually increase your radon level or create other potential hazards and additional costs. However, if you decide to do the work yourself, get information on appropriate training courses and copies of EPA’s technical guidance documents (see www.epa.gov/radon/pubs).
Will Any Contractor Do?
EPA recommends that you use a certified or qualified radon mitigation contractor trained to fix radon problems. You can determine a service provider’s qualifications to perform radon measurements or to mitigate your home in several ways. First, check with your state radon office. Many states require radon professionals to be licensed, certified, or registered, and to install radon mitigation systems that meet state requirements. 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, and if they follow industry consensus standards such as the American Society for Testing and Materials, ASTM, Standard Practice for Installing Radon Mitigation Systems in Existing Low-Rise Residential Buildings, E2121. You can contact private proficiency programs for lists of privately certified professionals in your area. Such programs usually provide members with a photo ID card, which indicates their qualifications and the ID card’s expiration date. For more information on private proficiency programs, visit www.epa.gov/radon/radontest.html, or contact your state radon office.
How to Select A Contractor
Get Estimates
Choose a contractor to fix a radon problem just as you would choose someone to do other home repairs. It is wise to get more than one estimate, to ask for references, and to contact some of those references to ask if they are satisfied with the contractors’ work.
Use this checklist when evaluating and comparing contractors and ask the following questions:
| Will the contractor provide references or photographs, as well as test results of before and after radon levels of past radon reduction work? | ||
| Can the contractor explain what the work will involve, how long it will take to complete, and exactly how the radon reduction system will? | ||
| Does the contractor charge a fee for any diagnostic tests? Although many contractors give free estimates, they may charge for diagnostic tests. These tests help determine what type of radon reduction system should be used and in some cases are necessary, especially if the contractor is unfamiliar with the type of home structure or the anticipated degree of difficulty. See “Radon Reduction Techniques” for more on diagnostic tests. | ||
| Did the contractor inspect your home’s structure before giving you an estimate? | ||
| Did the contractor review the quality of your radon measurement results and determine if appropriate testing procedures were followed? |
Compare the contractors’ proposed costs and consider what you will get for your money, taking into account: a less expensive system may cost more to operate and maintain; a less expensive system may have less aesthetic appeal; a more expensive system may be best for your home; and, the quality of the building material will affect how long the system lasts.
Does the contractor’s proposal and estimate include:
| Proof of state certification, professional proficiency or certification credentials? | ||
| Proof of liability insurance and being bonded, and having all necessary licenses to satisfy local requirements? | ||
| Diagnostic testing prior to design and installation of a radon reduction system? | ||
| Installation of a warning device to caution you if the radon reduction system is not working correctly? | ||
| Testing after installation to make sure the radon reduction system works well? | ||
| A guarantee to reduce radon levels to 4 pCi/L or below. And if so, for how long? |
The Contract
Ask the contractor to prepare a contract before any work starts. Carefully read the contract before you sign it. Make sure everything in the contract matches the original proposal. The contract should describe exactly what work will be done prior to and during the installation of the system, what the system consists of, and how the system will operate. Many contractors provide a guarantee that they will adjust or modify the system to reach a negotiated radon level. Carefully read the conditions of the contract describing the guarantee. Carefully consider optional additions to your contract which may add to the initial cost of the system, but may be worth the extra expense. Typical options might include an extended warranty, a service plan improved aesthetics.
Important information that should appear in the contract includes:
| The total cost of the job, including all taxes and permit fees; how much, if any, is required for a deposit; and when payment is due in full. | |
| The time needed to complete the work. | |
| An agreement by the contractor to obtain necessary permits and follow required building codes. | |
| A statement that the contractor carries liability insurance and is bonded and insured to protect you in case of injury to persons, or damage to property, while the work is done. | |
| A guarantee that the contractor will be responsible for damage and cleanup after the job. | |
| Details of any guarantee to reduce radon below a negotiated level. | |
| Details of warranties or other optional features associated with the hardware components of the mitigation system. | |
| A declaration stating whether any warranties or guarantees are transferable if you sell your home. | |
| A description of what the contractor expects the homeowner to do, such as make the work area accessible, before work begins. |
What to Look for in a Radon Reduction System
In selecting a radon reduction method for your home, you and your contractor should consider several things, including: how high your initial radon level is, the costs of installation and system operation, your home size, and your foundation type.
Installation and Operating Costs
Most types of radon reduction systems cause some loss of heated or air conditioned air, which could increase your utility bills. How much your utility bills will increase will depend on the climate you live in, what kind of reduction system you select, and how your home is built. Systems that use fans are more effective in reducing radon levels; however, they will slightly increase your electric bill.
