Radon Gas is an odorless, colorless gas that can build up in your home. It is a known carcinogen and the second leading cause of lung cancer (right behind smoking) according to the US Environmental Protection Agency (EPA) and the Centers for Disease Control and Prevention (CDC).
The CDC reports that Radon induced lung cancer kills about 21,000 people in the US each year—that’s about twice the number the National Highway Traffic Safety Administration reports were killed in drunk driving crashes in 2018. It’s around six times the number of drowning deaths and eight times the number of people killed in home fires each year. Of those 21,000 lung cancer deaths, about 2,900 occur among people who have never smoked. It is the single leading cause of lung cancer among non-smokers.
How do we know Radon is bad for us?
Scientists first discovered the harmful effects of Radon gas after occupational studies of miners showed those exposed to Radon gas over time had developed higher than normal rates of lung cancer. There was initially some debate about whether the data applied to Radon gas in the home. In 2005, that debate ended after two studies—one in North America and one in Europe—both confirmed the radon health risks predicted by the occupational studies. They found that breathing low levels of radon, like those found in some homes, leads to an increased risk for lung cancer.
Where does Radon gas come from?
Radon gas is radioactive. It is a natural byproduct of mineral breakdown that is all around us. The United States is a mineral rich nation. This is especially true in the Midwest. One of the minerals found in our soil is uranium. It is present in small amounts in many kinds of rock. Over time, uranium breaks down. When it does, it releases radioactive radon gas.
The radon gas moves up through the soil and water, eventually making its way into the atmosphere. That’s not a problem outdoors, where the gas can dissipate into the air, harming no one. The problems occur when radon gas builds up indoors.
There is generally some Radon present in all homes according to the EPA. Prolonged exposure to even moderate levels of radon is a health risk. The EPA strongly urges mitigation when a radon test indicates radon levels at or above 4.0 pCi/L (picocuries per liter). That’s because Radon is a known carcinogen or cancer-causing agent. The harmful effects of radon exposure happen over time. The stronger the concentration of Radon and the longer one is exposed to it, the higher the risk of developing lung cancer.
How can I find out if my home has a Radon problem?
Since Radon gas is odorless, you can’t smell it. It has no color or opacity, so you can’t see it. It has no flavor, so you can’t taste it. The only way to know if there is Radon building up in your home is to test for it. Testing is simple, inexpensive, and can be done as part of the home inspection when you buy your home, or at any time thereafter.
There are various types of radon tests. Some require leaving testing material in place for several months or more. Others can be completed in as little as a few days. Home testing kits are available at your local hardware store. These are inexpensive and fairly easy to use, but they lack tamper-resistance and protection from test interference, so can yield false results. Most real estate transactions rely on professional testing by certified technicians using sophisticated equipment.
What kind of test is used for real estate transactions?
The most popular Radon tests for real estate transactions are performed using machines called Continuous Radon Monitors (CRM). The CRMs are placed in the lowest livable level of the home (generally in the basement if there is one). One CRM must be place over each foundation type, because different foundation types allow differing amounts of Radon to seep inside. One machine can cover an area of up to 2,000 square feet. So, additional CRMs must be placed in larger homes. Readings are taken over a minimum of 48 hours.
Since Radon gas is radioactive, CRMs measure the amount of radioactivity in the atmosphere. The current standard of measure is picocuries per liter (pCi/L). A picocurie is a measure for the intensity of radioactivity contained in a sample of radioactive material. In a Radon test, it’s the air inside the home that is sampled and measured for radiation. The results indicate the average radiation level per liter of air over a 48-hour period. Once the testing time has elapsed, the data can be downloaded and read right away. This quick turn around makes this a very reliable way to get an accurate radon assessment of the home before the sale is complete.
Can any inspector test for Radon gas?
Radon testing using CRMs should be performed by trained radon technicians. Some states, like Illinois, require a licensed radon technician perform the test for real estate purposes. Licensed technicians must take a qualified radon measurement course and pass a state exam. In other states, like Missouri, state licensing isn’t required or offered. Both the primary professional organizations for home inspectors, the American Society of Home Inspectors (ASHI) and the International Association of Certified Home Inspectors (InterNACHI) offer certification classes and exams for Radon measurement technicians. So even in states that don’t license radon measurement technicians, a qualified radon inspector should have a certification that shows they are competent to conduct CRM radon tests.
Is it possible to cheat the Radon test?
People do occasionally try to cheat the test, but a professional Radon inspector knows the signs. CRMs
have tamper warnings that alert the technician if someone tried to move or adjust the machine. Tampering will invalidate the test. Some will try to manipulate the room conditions to improve the test results. For instance, you can’t just open a window and let it out. That might clear some Radon from the room, but it’s a short-term fix at best and it can even elevate radon levels under the right circumstances. Since Radon seeps in through small gaps and cracks in the foundation, propping open windows and doors can create a stack effect, accelerating the process and sucking more radon gas into the home.
CRM tests require “closed house conditions,” meaning doors and windows can’t be left open during the test; window unit air conditioners that draw air in from outside must be turned off, along with attic and whole house fans. To circumvent would-be cheaters, the test throws out the first few hours of readings. And a trained Radon measurement technician can often spot attempts to circumvent the test by the way the readings change over the course of the test. If it looks suspicious, the inspector can declare the test invalid, and re-test the home.
How much Radon is too much?
According to the EPA a Radon level of 4.0 pCi/L in your home may be equivalent to smoking 10 cigarettes a day. That’s what the EPA calls the Radon Action Level. At or above this level, the EPA recommends you take corrective measures to reduce your exposure to Radon gas.
Can you fix a home with a Radon problem?
An elevated Radon test result shouldn’t derail most home sales. Radon can be mitigated from most homes. If the results show elevated levels of radon, a professional can install a system to safely remove the radon in the home through a process called Radon mitigation or abatement. A Radon mitigation system will move the gasses from the soil beneath the home and vent them up into the atmosphere where they will safely disperse. Having a Radon mitigation system installed in most homes in the St. Louis area can cost several hundred dollars to a few thousand dollars. It’s a relatively small price to pay to keep your family safe in the home you love.
New homes can be built with Radon resistant features. Homes built in Illinois after 2014 are required to have a passive Radon mitigation system in place—that is, the vent pipes that allow the air to move up and away from the foundation must be built into the home. Missouri does not require passive mitigation system be built into new homes, but many builders do include them in their designs, and most will add them if you request it.
Sometimes a passive Radon mitigation system doesn’t remove enough Radon gas from the soil, and dangerous amounts still build up inside the home. A Radon mitigation professional can strategically place fans inside the system to effectively draw the gas up and away before it has time to seep into your home. These systems are referred to as active Radon mitigation systems. They are generally very effective at keeping Radon gas out of your living space.
Which homes should be tested?
The EPA recommends testing your home for Radon gas every two years. This is especially important if your home has a Radon mitigation system installed. But all homes should be tested periodically, since soil changes over time, and the gasses being released under your home two or three years from now may differ greatly from those released today.
Testing is also recommended after large construction and landscaping projects near your home, as these can disturb the soil enough to change the flow of Radon gas. Many realtors and lenders also advise their clients to have a radon test done with their home inspection. That way, there’s time to address the issue should Radon be a problem in the home. For more information, download the EPA’s guide to Radon for home buyers and sellers.
Remember, your home is where you and your family spend most of your time.
Just as it’s important to protect your investment with a professional home inspection, it’s important to protect your family with a Radon test performed by a licensed and certified Radon measurement technician.
If you are buying a home, Hawley Home Inspections can perform a Radon test alongside your home inspection. We also serve sellers who want to get ahead of any problems the properties they are selling may have, or to check if existing Radon mitigation systems are functioning properly. Even if you’re not planning a move, we can test your present home to make sure you don’t have a Radon problem. We also test small offices and businesses concerned about keeping their employees safe. Call for pricing.