 All over America, people are taking the national radon test. Have you? Answer true or false. Radon is a radioactive gas. True. I didn't know that, no. True or false. The Office of the Surgeon General recommends that all homes be tested for radon. True. Your home should be tested. True or false. Radon is the second leading cause of lung cancer. True. I'm going to dial the number and call. 1-800-SOS-RADON. Keep your family safe from radon. Call now. 1-800-SOS-RADON.