Radon, a radioactive gas originating in the soil, rock and water beneath a house’s foundation, is extremely hazardous to our health. Odorless, colorless and tasteless, it is impossible for humans to detect radon without the use of specialized equipment.
Radon Detectors are used to monitor the amount of radon inside a home or other building. There are two main types radon detectors: passive and active.
Here’s how they work:
Passive Radon Detectors
Passive radon detectors do not require any power source, and they are designed to be left in place for a certain amount of time. They work by allowing radon to enter the detector, where it is trapped on a material such as charcoal or plastic. There are three main types of passive radon detectors:
Charcoal Canister and Charcoal Liquid Scintillation Radon Detectors are used for short-term testing, usually from 2 to 7 days. They absorb radon or its decay products on activated charcoal.
Alpha Track Radon Detectors are designed for long-term monitoring, typically over a period of 3 to 12 months. They contain a small piece of plastic that gets etched by alpha particles, which are emitted by radon and its decay products.
Electret Ion Radon Detectors can be used for either short-term or long-term testing. They consist of a Teflon disc (the electret) that is statically charged. When radon decays, it produces positively charged ions that reduce the voltage on the electret. The voltage decrease is proportional to the radon concentration in the air.
At the end of a passive radon detector’s testing period, they are sealed and sent to a lab for analysis.
Active Radon Detectors
Active radon detectors require a power source such as batteries or electricity. They continuously monitor the air for radon (continuous radon monitors and continuous working level monitors are two main options), and they provide real-time results.
Active radon detectors are more expensive than passive detectors, but they are more convenient and provide more accurate results.
The Difference Between Short- and Long-Term Radon Detectors
Short-term radon detectors are often used to get a quick snapshot of radon levels in a home or building. Inexpensive and easy to use, short-term detectors work by being placed where it will not be disturbed, such as a bedroom or living room.
Long-term radon detectors, on the other hand, are more expensive than their short-term counterparts, but they provide a more accurate measurement of radon levels over time. Placed in a similar room, the detector is left in place for several months to a year before being removed for testing.
Why such a long time? Compared to short-term detectors, which can only gain a snapshot of radon levels over a brief period of time, long-term detectors provide an accurate picture of radon levels since they can vary from season to season.
Five Key Radon Detector Tips
Radon detectors should be placed in the lowest level of your home, where you spend the most time. This is because radon is heavier than air, and it tends to accumulate in basements and crawl spaces.
The detector should be placed in a room that is used regularly, such as a living room or bedroom, and it should be at least three feet away from any walls, windows or doors.
Keep windows and doors closed during the testing period. This will ensure that the results are accurate and representative of the radon levels in your home.
If you have a radon mitigation system in place, it’s still recommended to test your home regularly to ensure that the system is working properly.
When the testing period is over, you or a radon mitigator can send the detector to a laboratory for analysis. The lab will provide you with a report that shows the average radon level in your home over the testing period. If the radon level is above the recommended action level of 4 pCi/L (picocuries per liter), take steps to reduce those levels.
Verify Your Home’s Radon Levels
Your home may have zero radon or safely low radon levels … or it may be above the recommended action level. Why take chances? Know for sure and proceed with confidence and safety by testing your house for radon and taking the necessary steps to mitigate it.