Short-term radon tests are the quickest ways to test for radon in your home. These radon test kits should remain in the home from 2-90 days, depending on the device. Radon testing must be done for at least 48 hours. Some radon testing devices may be exposed for a longer time. Because radon levels tend to vary from day to day or season to season, a short term test is less likely than a long-term test to tell you your year round average radon level.
For homes, the EPA recommends that initial radon testing devices be short-term tests placed in the lowest lived in level of your home. Short-term radon testing under closed-building conditions helps to ensure that residents quickly learn if a home contains a very high levels of radon. If you are doing a short-term test close your windows and outside doors and try to keep them closed as much as possible during the testing time. You should not conduct short term radon testing during unusually severe storms or periods of unusually high winds.