Which location is likely to have higher levels of radon exposure?

Basements and underground structures are likely to have higher levels of radon exposure because radon is a naturally occurring radioactive gas that originates from the decay of uranium in soil and rock. This gas is more likely to accumulate in enclosed spaces that are below ground level, such as basements, where there is less ventilation compared to the outdoor environment. Radon can seep into these areas through cracks in the foundation, construction joints, and other openings, leading to potentially elevated concentrations.

In contrast, suburban areas with low housing density generally have better ventilation and are less likely to trap radon. Open fields with high vegetation may also allow for airflow and dispersal of gases, which can reduce the concentration of radon. High-rise buildings in the city center, being elevated and having more ventilation compared to lower structures, typically experience lower levels of radon exposure. Thus, underground locations like basements are most susceptible to higher concentrations of radon.