We bought one Airthings Corentium radon detector in 2021 and another one several months ago in 2022. They both are placed at my living room side-by-side. One Corentium radon detector measured radon level above 3 pCi/L constantly and sometimes above 4 pCi/L when heater has been turned on; however, the other Corentium detector measured radon level always below 2 pCi/L. The difference between the two meters is in the level of 1.5pCi/L apart. One Airthings radon detector is telling us the radon level is too high in the house and I need a mitigation system installed (which could cost thousands of dollars), while the other Airthings radon detector is telling us it is perfectly fine and no action will be needed. I have contacted Airthings Customer Care about the problem with their radon detectors, and what is the confident level of their product qualities. After weeks of back and forth of correspondences, they were not able to provide me with an answer or solution, rather they recommended me to buy professional grade radon detectors. I rate the Corentium radon detectors very poorly. They are useless. Don't waste your money.