Kevin King bought his three-story Gouldsboro home in 2002 and did not test for radon before buying. A transplant from North Carolina, he said he wasn’t worried because his new house had a slab foundation, not a basement.
“But looking at articles and on the web, we sent away for a test kit,” he said. “Nothing better to do, and why not?”
Radon is odorless, tasteless and invisible — and can be deadly. It’s a radioactive gas that naturally forms from uranium deposits in the Earth’s bedrock and also may seep into well water. And since Maine has plenty of uranium in its bedrock, home radon levels are among the highest in the United States.
Radon is the leading cause of lung cancer among nonsmokers, with about 165 nonsmoking Mainers dying from radon-caused lung cancer each year, Maine Radon Coordinator Jon Dyer noted. In well water, radon is connected to stomach cancers, according to the Maine Department of Health and Human Services (DHHS).
But don’t panic. Maine takes radon detection and removing it from residential air and water very seriously. Plus, it’s simple and inexpensive to test your home for radon.
“The only way to detect it is to do a test, and there’s a couple different ways today that that can be done,” said Mark Beauregard, who owns Radon Mitigation Services of Maine in Holden. “Number one, you can find radon tests at hardware stores and Home Depot and Lowe’s.”
These tests are mostly from out of state, from labs registered in Maine to meet Department of Health and Human Services (DHHS) standards and criteria.
“They send it to you for nothing,” Beauregard said. “You pay for them to read it.”
The cost to analyze the tests range from $35 to, for dual water and air testing, $100.
For new home buyers, radon testing is often part of the home inspection. But even if levels don’t read high from a first test, DHHS recommends testing every two to three years because radon levels fluctuate from natural circumstances, like storms or heavy winds.
A level below 4 picocuries (pCi) per liter is considered safe enough for homes, although 2 pCi per liter is significantly less risky. One picocurie is one-trillionth of a picocurie.
“At 4 pCi it’s actionable,” Dyer said. “We like to see it below 2 pCi.”
The average radon level in Maine is about 4.3 pCi per liter, while the national average is only 1.6 pCi per liter, although those amounts can vary from county to county.
“It’s not, do you have too much? It’s how much do you have?” Dyer said.
King’s home radon test showed a level of 5.4 pCi. He retested his home and the level rose to 6.6 pCi.
So he sent away for a monitor, available for about $200, which are also available at hardware stores. The monitor showed a level of about 7 pCi.
“Every time we did it, it kept going up,” King said.
Next, he began filling in the gaps between his home’s slab and walls.
“That didn’t work,” he said. “I’m radon 101. All I knew was, I think I have a problem.”
King called Beauregard, who determined that frost walls starting below and rising higher than the slab created an upside-down box beneath the house — just like a basement does — where negative pressure drew air up from the box into the air the Kings breathed every day.
“That hot air up above is just a big pull on this building,” Beauregard observed. “Kevin is the perfect example of getting everything sealed up and [radon] still finds its way through.”
Today, King’s radon levels are well below 1.0 pCi because a fan draws air from below the slab up through a pipe to outside the house. King had already taken care of sealing up the gaps, although that is only the first step, Beauregard noted. Now, the only thing King does is keep an eye on is a radon thermometer on the pipe in his garage.
“The numbers mean something to me but not to him,” Beauregard said. “All he needs to be concerned with is that the number on the right side is higher.”
For more information, visit the Maine Center for Disease Control and Prevention’s radon page at /www.maine.gov/dhhs/mecdc/environmental-health/rad/radon/hp-radon.htm.