Radon in Homes

The Massachusetts Department of Public Health recommends all homes be tested for radon. All buildings contain some radon. Buildings with high radon levels are found in every county in the Commonwealth.

The only way to know if radon is a problem is to test the air. If a building has private well water, the well water should be also tested for radon.

Fix your home if radon levels are 4 picocuries per liter (pCi/L) or higher. Think about fixing your home if radon levels are between 2 and 4 pCi/L.

If you hire someone to do radon testing or to fix a radon problem in your home, they should be certified by one of the following organizations:

  1. American Association of Radon Scientists and Technologists/National Radon Proficiency Program (AARST/NRPP) or
  2. The National Radon Safety Board (NRSB)

National radon standards are available for testing and fixing single-family homes and apartment buildings. These standards are available for viewing and/or purchase at https://standards.aarst.org/.

How to select a radon mitigation contractor

The U.S. Environmental Protection Agency (EPA) provides the following guidance for selecting a radon mitigation contractor (EPA, 2016):

Get Estimates

Choose a contractor to fix a radon problem just as you would choose someone for other home repairs. It is wise to get more than one estimate, to ask for references, and to contact  those references to ask if they are satisfied with the contractor’s work. Also, ask your state radon or consumer protection office for information about contractors.

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 work?
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 house structure or the anticipated degree of difficulty. See “Radon Reduction Techniques” in EPA’s Consumer’s Guide To Radon Reduction; How to Fix Your Home 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 contractor’s proposed costs and consider what you 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.

Check the contractors’ proposals and estimates for the following:

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 for how long

The Contract

Ask the contractor to prepare a contract before any work starts. 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 (e.g., 2 pCi/L or less). Carefully read the conditions of the contract describing the guarantee. Consider optional additions to your contract that 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, or 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 being done
  A guarantee that the contractor will be responsible for damage during the job 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

Source: Environmental Protection Agency, A Consumers’ Guide to Radon Reduction (2016)

For more information on radon in homes:

Contact for Radon in Homes



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