>>64173097
Less is more, most would say. If your home is constantly spiking upwards of 100Bq or more, then you'll need to have the home remedied with an active mitigation system. No level is technically safe. However, if you can bring it down to levels close to 100Bq or less than that would still be a vast improvement. The biggest problem with radon exposure is how long you stay in it. Being in a home that has moderate or less (400Bq) radon gas can potentially take decades for anything to show. Still, one should remedy the problem if one has the ability to do so. The active mitigation system is a one time install and you only need to replace its fan potentially every 10 years or so. My current reading, after installing an active mitigation system, is between 11 and 18Bq; the same concentration levels as being outside. I don't think i've ever seen my basement spike more than 35Bq after the install. Although it certainly helps that my home is sitting on top of gravel.