RADON MONITORING
Radon gas comes from the breakdown of radioactive materials in the Earth. It is an odorless and colorless gat that can leak through any crack or hole in the foundation of a home. It can build up over time to potentially hazardous levels. The Environmental Protection Agency (EPA) has determined an average level of over 4.0 piC/l (pico Curies per liter) during a monitoring period may be considered hazardous. They have determined long term exposure to levels higher than 4.0 piC/l may cause lung cancer, especially in smokers. The EPA website for radon is http://www.epa.gov/radon .
Radon gas has been detected in all 50 states. Some areas have higher levels than others. The EPA website ( http://www.epa.gov/radon/zonemap.html ) shows how levels can vary across the country. The only way to determine the levels in an individual property is to have it tested.
Radon monitoring can be done in two ways: Active and Passive. Active monitoring is typically short term, and is the type usually done to satisfy a contingency of a home purchase contract. A radon monitor is left in the lowest livable level of the home, usually the basement, for at least 48 hours. During the monitoring period, a "closed home" condition needs to be observed. The windows need to be closed during this time period. Doors can be used, but should not be left open for any length of time. Furnaces and air conditioners can be used normally. The monitoring should not be done during periods of high winds or heavy rains, as these can affect the results. Passive monitoring is a longer time period, anywhere from one week to one year. This involves leaving a test canister in the lowest livable level of the home. These canisters can be purchased online, and the monitoring can be done by the homeowner. After the predetermined time, the canister is sent to a licensed laboratory for analysis. The EPA website ( http://epa.gov/radon/radontest.html ) has information on the different type of tests and testing devices.
I use a Sun Nuclear Model 1027 continuous radon monitor. The monitor takes air samples each hour, and calculates an average for the monitoring period. The monitoring results are downloaded to a laptop at the end of the monitoring period, and the results are available at that time. Included with your inspection report will be a copy of the results. The results show the individual hourly readings, as well as the calculated average for the monitoring period. I try to place the monitor in the home in advance so I can have the results at the time of the home inspection. The monitor has a required yearly recalibration done by a professional radon laboratory. This documentation is available upon request.
Depending on the levels of radon that are detected, there are different options of mitigation. The areas can be ventilated, or sealed, to limit the amount of gas entering the property. A professional radon mitigation company can determine what options of mitigation would be best for the home, and can provide you with an estimate of the costs involved. Through proper mitigation, radon levels in the home can be lowered to acceptable ranges.
Please contact me if you have any questions about radon, radon monitoring, or to find out my charge for radon monitoring.