Radon In Air

Radon in Air: Frequently Asked Questions

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 Radon is a naturally occurring radioactive gas.

Radon comes from uranium in the soil, which is also radioactive. As the uranium goes through its half-life decay process it creates radon.

Radon gas can travel up to approximately 40 feet from its source through soil (depending on the soil porosity).

Our homes are under a slight negative pressure when closed up. This negative pressure is created by several normal household activities such as using a vented clothes dryer, bathroom vents, kitchen vent and through the use of central heat, wood stoves or fireplaces. Radon can also enter through domestic water, particularly if you have a drilled well.

The radon gas can find its way into the house through the smallest of cracks in a foundation or floor. The radon molecule is so small that if we were to compare it to the smallest of cracks, then a crack the size of a very fine human hair would be larger than the Grand Canyon if the radon molecule was blown up to baseball size.

Radon gas has a half-life of only 3.8 days. It typically reaches equilibrium after about 12 hours. It will vary in concentration over time, due to changes in atmospheric conditions. The radon concentration also changes with activities within the house such as cooking, laundry, heating, etc. but it does not build up when a house is closed over a long period of time as it further decays as part of the natural radiation decay process.

The only known health effect of radon is lung cancer. Radon is the second leading cause of lung cancer, second only to cigarette smoke.

Through the results of thousands of tests in the State of Maine it has been demonstrated that over thirty percent of homes in Maine have elevated radon. The average level in Maine is about 7.3 pCi/L.

A Pico Curie per liter (pCi/L) is a measurement of radiation energy in a liter of air which is one part per trillion. The EPA has established 4pCi/L as the action level.

In the State of Maine only licensed persons can test for radon unless you are an owner or a tenant of the property. Up-Country Building Inspectors has several licensed persons who are properly trained to test in accordance with the EPA’s protocol. We use the state-of-the-art E-Perm technique. Up-Country is licensed by the State of Maine as a radon laboratory. Our tests are analyzed in our own lab assuring our clients of prompt and accurate results.
Up-Country sets a minimum of three test kits, retrieves, analyzes and mails (also faxes) a written report and provides free follow-up consultation over the phone. Please visit the Radon Services section of our web site for details and pricing information.

In the vast majority of cases radon can be vented out of the house with a sub-slab depressurization system. This system works like a large vacuum cleaner that sucks the air out from under the basement floor and vents it out into the atmosphere above the roof. The components are basic plastic drain pipe (PVC) with the necessary fittings and a high quality fan that connects to the PVC pipe.

Generally the cost runs between $800 and $1500 to have a system installed. The installation of a system generally takes one to two days and needs to be done by a licensed contractor (although home owners can install systems in their own home). Up-Country does not install systems due to the potential conflict of interest.

No, generally tests are taken in the basement as well as the first floor. If results are elevated in the basement but not on the first floor, the decision to mitigate or not would depend on the dose rate (hours of likely exposure to the elevated radon). This needs to be discussed on a case-by-case basis. Follow up consultation is always available to our clients for any of our inspection services.