Radon is a colorless, odorless gas that occurs naturally in the earth. As elements like uranium and radium break down in the rock and soil beneath your house, they release radon gas. Uranium and radium are radioactive. The same is true for radon gas, which can cause lung cancer — in fact, radon exposure is the second leading cause of lung cancer in the United States. Radon can become trapped inside a home due to insulation and build up to unsafe levels. Because radon is odorless and invisible, the only way to know if you have a problem is to conduct a radon test. Our radon test takes 48 hours to process.