Clearing The Air: Radon

Most of us put time and attention into making our homes look and feel warm, comfortable and safe.  But one of the most important comfort and safety factors is something we can't see.  The quality of indoor air can make all the difference between feeling healthy and alert and feeling groggy or even ill.  Fortunatley there are ways to prevent air quality problems or fix them when they occur.

Radon
One of the most serious indoor air problems in the Southwest metro area is radon gas.  You can’t see, smell, or taste radon, but it could be present at a dangerous level in your home.  The Surgeon General has said that radon is second only to smoking as a cause of lung cancer.  Test kits are inexpensive, readily available at hardware and home improvement stores, and testing takes only a few minutes.  If your test is over 4 pCi/L, there is cause for concern, according to the Environmental Protection Agency.

Radon comes from the soil. Radon is produced from the natural decay of uranium that is found in nearly all soils. Uranium breaks down to radium. As radium disintegrates it turns into radioactive gas...radon. As a gas, radon moves up through the soil and into the air you breathe.


While radon is present everywhere, and there is no known, safe level, your greatest exposure is where it can concentrate-indoors. And where you spend most time-at home. Your home can have radon whether it be old or new, well-sealed or drafty, and with or without a basement.


High radon exist in every state in the US. In Minnesota, one in three homes (1/3) has radon levels that pose a significant health risk. Some factors that further contribute to Minnesota's high radon levels include:

• Minnesota's geology produces an ongoing supply of radon.
• Minnesota's climate affects how our homes are built and operate.

 

James Hunt, one of the owners of Quality Heating and Air Service, Inc. in Shakopee, says, "Some houses in Shakopee have had over 16 pCi/L.  It's amazing the number of houses that have had it."

Radon can enter a home through the floor and walls -- anywhere there is an opening between the home and the soil. Examples of such openings include dirt floor crawl spaces, unsealed sumps, cracks in slab-on-grade floors, utility penetrations, and the tiny pore spaces in concrete block walls. A basement, of course, provides a large surface area that contacts soil material.

Hunt says newer homes are built with a vapor barrier under the basement concrete, with drain tile that collects the gas.  In older homes, however, "open sump pits funnel radon gas into the house.  That's a big health hazard."

Radon levels are often highest at the entry point-typically in the lower part of a building. As radon gas moves upward, diffusion, natural air movements and mechanical equipment (such as forced-air ventilation system) distribute the radon through the home. Radon gas becomes more diluted in the upper levels of the home because there is more fresh air for it to mix with.


Greater dilution and less house vacuum effect occur when the house is more open to the outdoors, as during the non-heating season. This generally results in lower indoor radon levels in the summer compared to the winter.

Understanding how radon moves through the home environment helps to explain why timing and location are important factors to consider when conducting a radon test.

There are many companies in Minnesota that can help with mitigation of Radon.  The Minnesota Department of Health has a webpage devoted to mitigation companies.    With the cost of an average mitigation being $1500 - $2000, there is a substantial savings by doing it yourself. Click here for link to resources for do-it-yourselfers.



Source:  Refine Your Home magazine by Laura French, and Minnesota Department of Health: Radon in Minnesota Homes