b'RADON GASRadon is a radioactive gas that comes from rocks below the soil. All parts of the United States have radon in the soil, but some areas are at higher risk because of the local geology. Radon can enter a home through cracks or openings in the foundation. If a home is not properly sealed and ventilated, radon can build up in your indoor air and increase your chance of developing lung cancer.ONE OUT OF 15 HOMES HAS HIGH RADON LEVELS.RADON EXPOSURE IS THE SECOND LEADING CAUSE OF LUNG CANCER IN THE U.S. BEHIND TOBACCO SMOKE.ABOUT 21,000 PEOPLE DIE FROM RADON-INDUCED LUNG CANCER EVERY YEAR, WHICH IS MORE THAN THE TOTAL NUMBER OF DEATHS FROM OTHER HOUSEHOLD DANGERS LIKE FALLS, FIRES, DROWNINGS, OR ACCIDENTAL POISONINGS.'