Are there different types of test kits? Which should I use?
There are two basic types of kits: short term kits (2 to 90 days) and long term kits (90 days to 1 year), the most common type of short term kit is the charcoal canister and the most common type of long term kit is the alpha track detector. The long term radon test kits take into consideration seasonal variation, which can be substantial and therefore provide a better measure of annual average radon exposures than short term tests. If a short term test result is greater than 4pCi/L, EPA recommends following up with a long-term, or a second short-term test, to confirm the result. If your initial reading is over 10pCi/L only a short-term test should be used for follow-up.