This library exists because radon generates more confusion than almost any home problem — an invisible gas, an unfamiliar unit, and advice that arrives mid-crisis. The guides below cover the questions that actually come up: what a high test result means and what to do about it, how a mitigation system works piece by piece, how radon plays out in a Pennsylvania home sale, and how to tell whether an existing system is still earning its keep. Each one is written to be read calmly, start to finish. For quick one-paragraph answers instead, the FAQ page covers the short version of nearly everything here.