It's a clear and odorless gas called radon. We mailed 16 radon test kits to homes across Utah. Six of the nine test kits, mailed to a lab for results before this story aired, uncovered dangerous levels of radon in the homes.
Connie Nordgren's home in Sandy tested the highest at 26.2, which is alarming. The EPA strongly recommends homeowners take action if a test kit finds a level of four or higher.
"That really concerns me. All of my loved ones have been in the basement," she said.
Experts say radon is a problem in Utah because of our unique geography. Uranium is pushed closer to the earth's surface by our mountains and when it decomposes that uranium produces radon gas.
This gas sits underground in open spaces, but often seeps into homes through basement cracks.
Then the radon gas makes its way inside your lungs where it can cause cancer.
"So are you surprised by the test results?" asked ABC 4's Noah Bond. "Yes. I didn't expect to have a level that high," replied Nordgren.
If 100 people lived in her basement for a lifetime, four would likely die of lung cancer.
Concerned with these findings, ABC 4's Noah Bond dug deeper into Utah's radon problem by tracing every radon test recorded by the Utah Department of Environmental quality in Utah in the last year; a total of 17,483.
The results reveal nearly four in every ten homes have radon levels above federal guidelines. Counties with the highest average level of radon are Beaver, Sevier, and Wasatch.
Charlie McQuinn wishes he knew about the dangers before discovering the tumor in his lung.
"Thought we ought to test, but just never got around to it because it didn't seem like something that was really threatening," said McQuinn.
Surgeons removed the upper portion of his left lung to save his life.
A test revealed a radon level of 4.1 in Charley's basement; far below Connie's 26.2 radon level, but still high enough to be a concern.
"I'm actually grateful that ours wasn't much higher because people would say, 'Well mine isn't any ways near that,'" McQuinn said.
And not only Charlie had health issues; three of his children with basement bedrooms developed cancer as well. They're alive thanks to life saving treatments.
"Now I know that I should have tested and it's easy to get rid of. It doesn't cost that much and I could have been free of lung cancer," said McQuinn.
So why aren't people testing their homes? ABC 4's Noah Bond discovered there are a lot of excuses..
"We looked at maps of the area that look at radon concentrations and our was not in an area that had a high radon concentration," said Ron Martin from Draper.
"I haven't because I have smoke detectors and it does the same thing it tests for radon too as for as what I was told," said Peggy Vernon from Vernal. This is actually is a misconception.
ABC 4 found the biggest setback is no one seems to know what a radon test costs. "To be honest with you, I'd be guessing, but probably around $100," guessed Martin.
It's way less, actually results cost a little effort, five first class stamps and $6. "Oh really," said Vernon. "Now with that information would you test your home for six dollars?" asked Bond. "Sure," Vernon replied.
"If that's the cost then I probably would get my home tested," said Martin.
And as the people who participated in our ABC 4 investigation learned; a little knowledge and money can save your life.
"I'm going to do a little research and call a company in and get this taken care of," said Nordgren.
The State of Utah has made arrangements for Utah residents to purchase Radon test kits at a reduced rate. This offer is limited to State of Utah residents only. The kits cost $6.
The EPA estimates radon kills 21,000 people in the United States every year.