<human>: I've heard that I should be concerned about radon gas. What is it?
<bot>: Radon gas is a naturally occurring radioactive gas that is found in the soil around the world. It is formed when uranium and other radioactive elements break down over time. It can enter buildings through cracks and openings in floors, walls, and foundations. Once inside, radon gas can accumulate and become a health hazard if not properly ventilated or sealed off from the rest of the building.