Over the two decades Don Fredal spent working first as a home builder and then as an inspector in Kansas City, he didn’t take warnings about the risk of radon exposure seriously.

In the back of his mind, he suspected the radon mitigation and prevention industry of scamming innocent homebuyers into paying for unnecessary infrastructure.

But in 2014, Fredal was diagnosed with advanced small cell lung cancer, which had metastasized into the bones of his spine, clavicle, rib cage and eventually, his brain and hip.

After ruling out a number of other carcinogens — Fredal is a nonsmoker — Fredal and his doctor determined that the cancer was likely caused by radon exposure from the various homes Fredal lived in throughout his life. Fredal was 44 years old; his sons were 7 and 9. He was told he had 18 months to live.

Norman was the lead editor for the video.