If you are buying or selling a home, the subject of radon testing is likely to come up. But everyone needs to know how much radon is present in their environment because high levels are deadly.
Radon is a natural byproduct of uranium breaking down in the rocks and soil. It is a colorless, odorless, and tasteless radioactive gas and a chemical element.
Radon inside a structure comes from the ground it sits on. No one can assume that, just because a neighbor’s house tested with a low radon level, then your home will be equally safe. It all depends on what is in the dirt underneath a building.
People who have owned their homes for years – generations, even – may be unaware that they are sitting on a sitting time-bomb where their health is concerned.
Indoors, radon can become a health hazard because the earth continually breaks down, releasing poisonous atomic particles into the air. When inhaled, radon particles can alter the DNA and increase the risk of lung cancer.
Radon is ranked the #2 cause of lung cancer in the U.S. The Environmental Protection Agency (EPA), which sets federal limits for tolerable levels of known toxins, puts radon in its “Class A” carcinogen category.
Asthma and other respiratory disorders have not been linked to radon exposure.
Radon is measured in picocuries per liter (pCi/L) of air and tested for its concentration. The EPA recommends that if the concentration of radon is 4 pCi/L or greater, then remediation should be done to lower risks.
Smoking tobacco products along with radon exposure increases greatly the risk of cancer.
The EPA and U.S. surgeon general advise that all floors below the third be tested for radon. The air in most homes will pose no threat from radon contamination but soil in certain parts of the country is reportedly higher in recorded radon levels.
The next reasonable question for many people right now is, “How can I test the air in my crib for poisonous radon?”
The answer is that you can buy a Do-It-Yourself kit at your local home improvement store or hire someone else to do it for you. Those who choose to outsource this important assay of atmospheric radon are advised to look for members of the National Radon Safety Board (NRSB) or the American Association of Radon Scientists and Technologists (AARST) National Radon Proficiency Program (NRPP).
If you want to go it alone, get a radon measurement device listed by the EPA’s Radon Measurement Proficiency Program and follow the directions exactly. Passive testing for radon is both easy and simple. A kit from a home improvement store ranges from $10 to $30.
Several building inspection companies I contacted charge $125 for a radon test which requires setting up and then letting it sample the air for at least 48 hours for analysis.
I found out that there are two types of radon test kits:
- Short-term testing takes 2 to 90 days depending on the type of device used
- Long-term testing takes longer than 90 days
Most tests, be they DIY or by a commercial technician, are short term. While these briefer tests don’t tell you the average level of radon for throughout the year, they can point to a detectable, concerning, high radon level in the air you breathe.
No matter how long sampling is done, a radon test must be done properly or the results won’t count for much.
- Windows and exterior doors should be kept closed as much as possible during the test. For 2-3 day tests, shut all the windows and doors for 12 hours before the test.
- Don’t conduct a radon test during storms or high winds.
- Put the test kit 20 inches above the floor in a place where it won’t be disturbed in a room that gets regular use – but not in the kitchen or bathroom.
- Leave the kit out for the specified time.
- Seal the kit.
- Mail the kit to the lab.
- Expect to receive the lab results in about two weeks
Long-term radon tests come mostly in two types: alpha track testing and electrets detectors. Be aware that some of these types can be short-term so read the box labeling carefully if you are doing this yourself.
The longer you collect radon changes the average. If you happen to sample your home’s air for radon right after a soil release, the level might well be higher than if you captured particles for several more months with low radon emissions.
The vast majority of DIY radon testing kits (95 percent) use activated charcoal to collect radon atoms from the surrounding air for counting in a lab later. These tests are easily affordable.
Similarly, an alpha track device is a specialized piece of plastic that is marked when alpha particles in radon strike it. The hits can be counted in a laboratory later.
Professional radon inspectors use a more expensive piece of analytical equipment called an electret. This plastic disc holds an electric charge and requires expertise to operate safely and correctly.
The pros may also use a continuous radon monitor to measure radon for two days. This test is used in real estate transactions that require radon testing.