Radon is a colorless, odorless radioactive gas naturally occurring in the environment. It can build up in homes.
Home inspectors can test for radon and help their clients take steps to mitigate it if high levels are found. This service is a valuable add-on to a home inspection.
Alpha Track Detector
The Alpha Track Detector is the most common radon detector used during a home inspection. It is a passive radon detector that measures the average radon level in the home.
When radon atoms decay inside the Alpha Track Detector, they release alpha particles. These particles then strike the foil inside the detector, leaving microscopic tracks on the foil’s surface.
These tracks are then counted on an automated system to determine the radon level. This radon level is then reported in picocuries per liter (pCi/L) or becquerels per cubic meter (Bq/m3).
Liquid Scintillation Detector
Radon is a radioactive chemical that can cause health problems and is sometimes a carcinogen. The only way to know if your home has elevated radon levels is to have it tested.
A liquid scintillation detector (LSC) is one of the most common radon-detecting devices used by a qualified radon tester. It can detect a small amount of radon in the air and is often used as a long-term test.
Typically, the liquid scintillation detector is placed in a home and exposed to radon-containing air for a specific period. After the time is up, a qualified radon inspector sends the device to a lab for testing.
There are several types of liquid scintillation detectors. These include a charcoal liquid scintillation canister, alpha track detectors, and electret ion chamber detectors. The type of detector used will depend on the radon level being tested and the inspector’s preference.
Continuous Radon Detectors
Radon is a highly radioactive gas from decaying radon-containing materials in the soil and water. It enters your home through cracks in the foundation and walls.
If you’re a home inspector, you have several options for testing for radon. You can use a charcoal canister, liquid scintillation detector, or an active monitor.
Passive devices like charcoal canisters require no electricity and are generally used for short-term testing. They can be bought from hardware stores or mail and are less expensive than the more sophisticated active detectors.
Continuous radon monitors use electrical power to detect and record radon continuously. They’re also tamper-proof. That’s why they’re often recommended for sale homes or when a real estate agent is involved.
Radon testing techniques are available to reduce the amount of radon gas in homes. These include methods that prevent radon from entering the home or venting it to the outdoors.
A contractor can install a mitigation system during construction or after the house is completed, but it’s always best to do a radon test during a new home inspection. The type of soil, construction and foundation condition, and occupant lifestyle all affect the amount of radon that can get into the home.
The EPA recommends that homes with radon levels above the action level of 4 pCi/L be mitigated to lower those levels to less harmful levels. This is especially important for people with asthma, children, smokers, and elderly persons.