Colorado homes may hold a silent, odorless and radioactive gas: radon. Seeping up through the ground, it can collect in homes unless properly mitigated. Many homeowners may not know about the dangers of radon, like Heidi Nafman-Onda. She’s a lung cancer survivor who started the White Ribbon Project after radon caused her cancer. There are ways to test for radon and mitigate it, says Margaret Horton with the Colorado Radon Program. The state also has a radon mitigation assistance program for low-income families, and Denver resident Gail Sigman was a recipient.Real Talk is hosted by Colorado Public Radio's Nathan Fernando-Frescas and Denver7's Micah Smith.