Healthy Indoors Magazine
Issue link: https://hi.iaq.net/i/238907
Radon Continued from previous page level is. Most North American soils and rocks have some trace amounts of uranium in them. It is just the strength of that source that is variable. Pathways into the home are almost too many to list but some major ones are, exposed soil crawlspaces, sump pits, curtain drains from basement to soil, untrapped floor drains, box outs for HVAC system drains, cold joints between basement slab and basement walls, hollow block walls, and plumbing and electrical piping that has not been sealed. It only takes an aggregate 1 square cm opening to the soil if you have high source strength to have elevated radon levels in your home. Radon seeps into buildings because there is a pressure differential between the build- ing and the soil that surrounds it. To explain this in nontechnical terms, I often ask people to think about a soda pop cup, I ask them to imagine them taking a hold of the top of the cup with the lid off, now imagine it being pushed down into a bucket of water but don't let the rim of the cup go under the water. I then ask, why is the water trying to get into the cup? There is more pressure in the water surrounding the cup than is in the air inside the cup. What would happen if there were a couple of tiny holes in the soda cup? Yes, it would fill up. What happens when we stick a house into the soil with a basement? Yes the soil gas will seep in. You might ask: My home is slab on grade I am safe right? The next thing we must consider is the stack effect, when the warm air in a home comes up against the underside of the ceiling it migrates through pulling on the whole building and the soil and creating a stack effect on the whole building. So sorry, no, you are not safe. The only way to know what your radiation exposure from radon is: is to test your home or workplace for radon. Testing for radon is simple, bring in a certified radon testing professional, have a proper test conducted and then you will know. If you are more frugally minded and can follow detailed instructions you can buy a test kit from the internet, or even your local big box store. Remember to follow the directions completely, as a radon test that is improperly conducted and gives you a false low result, would be Healthy Indoors 27