What Is Radon? Radon is a colorless, odorless, and tasteless gas that is caused by the breakdown of naturally occurring uranium deposits under the soil. The Surgeon General has identified Radon as the second leading cause of lung cancer in the United States and is believed to cause approximately 22,000 each year. Many Americans unknowingly live with elevated levels of Radon gas in their homes. and it is recommended that all homes be tested when they come up for sale. If you are interested in Radon Testing your home book an appointment with a home inspector from Trademark Inspections today.