Saturday, February 18, 2012

Radon Hazards

      Radon is an odorless and colorless gas which emanates up through the soil as a natural product of the breakdown of uranium, from soil, rock, and also from water.   Radon is found in all fifty states in the US,  and in many places in Canada also.  It is likely found in many places in the world, but in the developing world less attention has been paid to it.    Normally, radon emanates through the soil, up through the basement, crawlspace or even slab, and out through normal air exchange and in many homes is simply not a problem, however it some homes, it can be.
This is an issue because as the radon emanates through the house, and people breathe the "radon daughters" this places them at higher risk for lung cancer.   In the US, radon is measured in picacuries per liter.  Any household measurement of less than 4 is considered acceptable, whereas higher may require some form of remediation.  In Canada, measurement devices which show a level of 200 Bq/m3 may place families at risk.
           Experts agree that about 90% of human lung cancer is caused by smoking, however the presence of radon in a home can cause smoking itself to produce even a higher risk of lung cancer, as the smoke can absorb the radiation which becomes concentrated from the ambient air in the smoke during smoking.
            One of the things which is quite amazing about radon, is that sometimes a very well built home, with tight walls and windows will have a much higher radon level than a house in the same area which is perhaps older and built less tightly.  There is no way of predicting which houses have high radon levels and which homes have low levels, other than simple measurement.   Measurement of radon is covered for the US and for Canada in the links below.  It is essential to measure ones home.  Although radon can be present in all types of buildings, we are at highest risk from radon in our homes because we spend the largest amount of time there, by virtue of sleeping there at night.  Lung cancer from radon is not something we get in a few days, or months, but something which our risk is cumulative over years.  US, Canadian and European studies have all borne this out.
           Many years ago, in the nineteen eighties, when we bought out very first small house in the country, and began raising our first two children, radon became an issue in the state in which we were living then.  Newspaper articles abounded concerning the hazards of radon, and experts came to town and county meetings about this "newly discovered hazard:".    Houses quite close to our own were found to have ridiculously hazardous levels of radon, and frankly, we were very frightened.   When we finally located inexpensive cannister type measurement devices for our own home, we were found to have a very low level there. It was true that we had a dirt floored cellar and no true basement walls, but the very construction which allowed radon to enter, was allowing radon to vent before it was getting into our living spaces.   Even when radon does enter living areas, there is much that can be done on the homeowner level, to vent or to remediate radon hazards.  Remediation of radon is also covered in the references I have provided below.    It is also possible to breathe radon while showering in some places, but ventilation of rooms also diminishes exposure in this situation as well.   One of the reasons our first home sold so well when it became time to seek a larger home, was that we had our radon certificate with our level from radon management in our paperwork, which was not required in that region, at that time.
           In our next state, no one had heard of radon.  We sent for radon monitoring devices and found a low level in our new home also. We assumed that in Virginia, this simply wasn't a problem.  However, in the late eighties,  once again, homes quite near our own were found to have high levels.  We had dodged a bullet once again.
          In each of the farm homes we built afterward, radon levels turned out to be higher than our previous homes.  In each of those we had a full basement, and these were finished areas, however, we did not have the same level of natural ventilation, unless we made a point of opening a window, or using a fan or cooling system.   In homes with living space in a basement, and especially in those with finished basement bedrooms, it is especially important that you purchase measuring devices and ascertain these levels, as per directions.

  1. Cracks in solid floors
  2. Construction joints
  3. Cracks in walls
  4. Gaps in suspended floors
  5. Gaps around service pipes
  6. Cavities inside walls
  7. The water supply

        For most people, radon measurement is a fairly easy and inexpensive process.   For most homeowners, reasonable, easy steps can be taken to diminish radon levels.   For a few, a professionally planned system might be necessary to result in radon abatement.  If one plans to remain in ones home and one has high levels, professional abatement may be intelligent.  We have been successful simply by keeping vents open and using open windows, and remeasuring, and we are once again, in a high radon area.  
         In Canada, a lot of the radon hotspots are in the interior of British Columbia.  A few years ago, Nova Scotia was found to have elevated levels in the region South of Halifax where there is uranium in the bedrock. Some of these areas are Tantallon,  Timberlea and St Margaret's Bay.  Other areas in Canada with higher than normal levels of radon may include Winnipeg, Elliott Lake, Kirkland Lake, Port Hope and Kitchener-Waterloo, Ontario, Oka, Quebec,  and Newfoundland.     In the United States, I have placed the US Geological Survey hot spots map below.  Remember that it is possible to live in a radon hotspot as we have twice now, and to own a home where radon is not excessively high in the home.  It is also possible to have a high radon level in a part of the country which is not yet known for radon, as uranium ore may be close to the surface, and may not have been identified yet in that region.

For the US:

For Canada:

These are the radon "hotspots" in the US.   Remember that you may well have a house in a hotspot with a low level of radon. We have done this now, twice.

Radon testing can be achieved a number of ways. In the US, a canister type tester can be purchased in a hardware store for about ten dollars. One follows the directions for sampling, and then mails the canister to the address inside the package in the mailer enclosed. A total pica-curie per liter determination is made, then the report is mailed to you. In Canada, you may need to specially order a kit from a larger hardware store. For those who need it, there are continuous radon monitors available.

Monitor information:

This is the continuous monitor sold by  There are many other types of cotinuous monitors for special uses.  Most households will only require the use of the canister style as shown below.

These are the inexpensive canister type radon testers which most households use.

REMINDER: Once you have measured your basement or house for radon, if indicated, please remember that if you have a local earthquake or a series of aftershocks, that the radon should likely be remeasured at your convenience. Following an earthquake, changes in the bedrock may occur that might permit new streams of radon to enter your home, thus changing the reading in different areas. Of course, it could also decrease the radon amount in your home. If you reside in an area with frequent earthquakes and with radon issues, you should research a continuous radon monitor, which sells for hundreds of dollars, but could well be worth it. In the US, it might also be worth asking FEMA if they could aid you in locating and paying for one.

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