Laura Seitz, Deseret News
In a basement stocked with emergency food supplies Charlie McQuinn, 71, shows the radon mitigation system in his Cottonwood Heights home on Thursday, December 1, 2011.

SALT LAKE CITY — Utah has some of the highest levels of radon.

"From the data we've collected, we estimate about a third of the homes in Utah will have elevated levels," said Christine Keyser, Utah's indoor radon coordinator.

"Everyone should test their home for radon," she said.

According to the Environmental Protection Agency, radon is the second leading cause of lung cancer and the leading environmental cause of cancer. Radon is a colorless, odorless gas that is a byproduct of decaying uranium. It can invade a home and, over time, make residents sick. People may not know it's there until it's too late.

Riverton residents Ken and Brenda Gallacher tested their home for radon shortly after moving in and found levels higher than the EPA's recommended average indoor radon concentration.

"It's something everyone should check. You cannot be in denial about this," Ken Gallacher said.

The Gallachers' radon report showed their home had a concentration of 12.5 picocuries per liter (pCi/L). The EPA recommends homeowners take action if their indoor radon concentration is 4.0 pCi/L or higher.

The Gallachers decided to install a radon abatement system, which significantly reduces radon levels and mitigates the risk of health effects.

"We've known what it's like not to have your health," Brenda Gallacher said. "There's nothing more valuable in life than having your health. The cost is well worth it."

The abatement system moves the radon from underneath the house, where the gas collects, and ventilates it to the outside.

"Having this done gives you piece of mind and makes your home a lot safer," Ken Gallacher said.

Ten homeowners whose locations stretch from Orem to Brigham City agreed to test their homes for radon. They agreed to share the test results if their last names were not used. Some homeowners, like Brian in Orem, knew what radon was but had put off testing.

"We have four kids, and we actually have one on the way in June," Brian said. "So it's kind of been on my mind for a while now."

Other homeowners, like Rebecca in Lehi, confused the gas with carbon monoxide. "We brought up carbon monoxide a couple times," she said. "But now that we have the baby, you think more about it."

"I do hear that," Keyser said. "I often hear people say, ‘We have an alarm system in our home that will set off.' I'm always thinking, 'That's for your carbon monoxide. There isn't an alarm system that goes off if you have radon.'"

Instead, Keyser suggests using an easy test kit.

Of the 10 homeowners that agreed to the tests, most homes tested normal, with radon levels ranging from .08 pCi/L to 2.9 pCi/L. Two tests came back at 4.0 pCi/L and 6.8 pCi/L, which is at or near the EPA's recommended action level respectively.

A home tested in Brigham City had the highest radon level: 11.9 pCi/L.

"I was surprised. I just figured it would be under 4.0 pCi/L," said Rod, the Brigham City homeowner. "You never think it's going to be you with the high levels. You don't know it, you don't have it type thing."

The Gallachers say, initially, they thought that, too. But when their test results showed such high levels, they knew they needed to act.

"It is real. It's very real, and it's something to be taken very seriously," Ken Gallacher said. "The word needs to get out that this does exist, and assuming it is not in your home is a dangerous game to play."