Originally Published: April 1, 2016 6 a.m.
According to Bob Brown, owner of Arizona Foundation Solutions, yes indeed we have radon in Yavapai County, and according to Bob “every house should be tested.” We have a higher dose of radon than other areas in Arizona.
Radon is an invisible, radioactive gas created from natural deposits of uranium and radium in the soil. Radon gas can be drawn into a building and accumulate to concentrations that can increase the potential for contracting lung cancer.
Most of the radon in Arizona homes comes from the natural deposits of uranium commonly found in Arizona soils and rocks. Unlike some other environmental concerns, elevated indoor radon is seldom caused by human intervention.
Radon enters a building through its foundation, basement, crawlspace or slab floor. As the radon rises inside the building, it is diluted with air that leaks through exterior walls and other openings. Consequently, radon levels are typically highest in the lowest portion of the home.
If a test is conducted in the lowest level of the home suitable for occupancy, with all the exterior doors and windows closed, the home’s owner or prospective buyer can be reasonably assured that exposures to radon in upper portions of the home are less than in the lower levels. It can also be assumed the indoor radon exposure would be less when fresh outdoor air is allowed into the home.
Radon is a gas that is created in soil where uranium and radium are found. These elements can be found everywhere in the world, but at different concentrations. Therefore, any building has the potential for elevated levels of radon. The more uranium found in the soil, the higher the potential for elevated radon levels within a building constructed upon that soil.
The question is not, “Is there radon?” but rather, “How much radon is there, and does it present a health risk to me?” Radon is an inert gas, which means it does not react or combine with the elements in the ground. Because of this, radon can move up through the soil into the atmosphere, where radon is easily diluted and presents little concern. However, when radon enters a building from the soil below, it can accumulate and become a health concern.
You cannot see or smell radon. There is no way that your body can sense the presence of radon, yet long-term exposure to elevated levels of naturally occurring gas can increase a person’s chances of developing lung cancer.
How does radon enter a home?
Radon concentrations are typically the highest in the lowest occupied portion of a home. Air inside buildings is typically at a lower pressure than in the soil below. The difference in air pressure causes radon and other soil gases to be drawn into the building.
Air pressure differences occur for a variety of reasons. For instance, exhaust fans, clothes dryers and other appliances can remove a considerable amount of air from a building. When air is exhausted, outside air enters the building to replace it. Much of this replacement air comes in from the underlying soil.
When interior temperatures are higher than outside temperatures, thermal effects occur inside of the building. Just as warm air causes a balloon to rise because the surrounding air is cool, warm air rises within a building and is displaced by cooler, dense outside air. Some of that outside air comes from the soil.
The rate at which radon enters a house may vary, depending on the forces that draw radon into the structure. Monitoring devices that measure radon over extended periods of time provide a better indication of actual, average exposure than short-term “screening” tests. The minimum duration of any test intended to determine the need for mitigation is 48 hours.
Radon also varies from season to season as a function of climate and the way the home is used by its occupants. The ideal residential radon test would be a yearlong test conducted under completely normal living conditions. However, a long-term test is usually unrealistic for the purpose of a real estate transaction.
Short-term tests measure a home’s potential for elevated radon levels, independent of the way occupants may actually use the house. The tests are conducted with all the windows closed and with all doors closed except for normal exit and entry. The test device is placed in the lowest area of the house currently used as living space or that may be occupied in the future. This EPA-recommended technique has become the accepted method of testing houses during real estate transactions.
Why should a home be tested?
Radon is a cancer-causing radioactive gas.
Indoor radon gas is a national health problem. Radon causes thousands of deaths each year. Millions of homes have elevated radon levels. Most homes should be tested for radon. When elevated levels are confirmed, the problem should be corrected. Radon is the second-leading cause of lung cancer in the United States, after smoking. The World Health Organization, The Surgeon General of the United States, the American Medical Association and the United States Environmental Protection Agency has labeled radon a significant health risk.
Any house can have high radon levels. Radon is a serious health risk and no home is immune to it.
No two homes, regardless of proximity, have the same radon exposure. Radon generally moves a distance of only 20 to 30 feet through the soil to a building. Consequently, the source for the radon entering a building is, generally, near or just beneath the building. Soils can vary from building to building, even within the same neighborhood. With the variability of soils and geology beneath homes, the only way to know if your home has elevated levels of radon is to test.
No law requires Arizona homeowners to reduce health risk from radon. Radon can affect your health; but once identified, it’s a problem you can control. Most Arizona households will not have a serious radon problem; but you will gain valuable peace of mind knowing whether your home is safe.
Safe and acceptable levels of radon are two different answers. A safe level of radon would be no radon at all.
The Radon Act 51, passed by Congress set the natural outdoor level of radon gas (0.4pCi/L) as the target radon level for indoor radon levels. Unfortunately, two-thirds of all homes nationally exceeded this level. The US EPA set an action level of 4 pCi/L. At or above this level or radon, the EPA recommends that you take corrective measures to reduce your exposure to radon gas.
There are no average radon levels for a specific city, state or region and it does not matter if your neighbor’s home was tested and was high or low, because results for your home may be completely different. Radon generally moves a distance of only 20 to 30 feet through the soil to a building and soils can vary from building to building even within the same neighborhood.
There are two basic types of radon gas testing devices, hiring a professional to perform the test or an inexpensive DIY test kit available through hardware stores. If you are radon testing to evaluate potential risk, a home test kit will do the job. The instructions for performing the test must be followed carefully.
While no level of radon gas is completely safe and with most things in life we must balance the benefits and costs to determine an acceptable level of exposure. When we drive every day we are subjecting ourselves to a potential accident, when we walk or go outside we are exposing ourselves to ultraviolet light and increasing our risk of skin cancer. People smoke, eats poorly and engage in activities that are dangerous. Radon is one of those risks that we all take. We can choose how we drive, what we eat, if we smoke or not, but breathing air in our home is something we have no choice over so there are some basic steps to take when buying or building a home or for that matter testing your current home.
If a short-term radon test is conducted correctly for a minimum of two days, under closed-house conditions, one can reasonably say, if the result is less than 4.0 pCi/L, the annual average of the home under normal lived-in conditions is also likely to be less than 4.0 pCi/L. If the level is at or above 4.0 pCi/L, the house has the potential to average more than 4.0 pCi/L, and you should consider follow-up testing or taking action to reduce (mitigate) the radon in the home.
There is no “totally safe” level of radon exposure. 4 picoCuries per liter is the “action level” recommended by the EPA and all radon problems can be fixed. Radon levels in homes can typically be reduced to between 2 - 4 picoCuries per liter.
YCCA has ordered several radon test kits so watch for more information and we will let you know when they become available.
Remember to tune in to YCCA’s Hammer Time every Saturday and Sunday morning 7 a.m. on KQNA 1130 AM/99.9 FM or the web kqna.com. Listen to Sandy to Mike talk about the construction industry and meet your local community partners.