The Inland Northwest has very high levels of radon in the soil. Over 50% of the homes in Kootenai County have levels greater than 4 picocuries/L, which is considered elevated and potentially harmful. The average level per home in this county is 13.7 pcs/L. Radon is an odorless, invisible gas produced by uranium breakdown in the soil which seeps into homes through negative pressure via cracks and crevices in the foundation. Levels are especially high in the winter, when homes are closed up in order to stay warm.
Radon is a known carcinogen. Long term exposure to this gas is the second leading cause of lung cancer, killing an estimated 20,000 to 30,000 people per year. Smokers exposed to radon have an especially high risk of contracting and dying from this deadly disease.
Homes should be tested for radon during the winter months when outside ventilation is at a minimum. Kits are inexpensive and can be purchased through many home-improvement stores or online at www.radonidaho.org. The testing device purchased is placed in the corner of the most dependent portion of the home and left undisturbed for 2-3 days, then mailed for analysis. Consistent results greater than 4 pcs/L warrant installation of a radon mitigation system. Placement of these devices typically cost from between $500 to $2500, and effectively vent radon from beneath the house safely to the outside.