Fig. 1
From: Economic valuation of health benefits from using geologic data to communicate radon risk potential
Example of radon zone map produced by United States Environmental Protection Agency and previously used by the state of Kentucky, USA to illustrate radon risk potential. Zone 1 represents counties with predicted average radon screening levels > 4 pCi/L, Zone 2 represents counties with predicted average radon screening levels of 2 to 4 pCi/L, and Zone 3 represents counties with predicted average radon screening levels < 2 pCi/L. Image is a United States government work not subject to copyright [26]. Image content has been slightly reorganized and enlarged to improve interpretability