Radon is all-natural, clear, odorless, tasteless, inert — and deadly.

And it’s a killer that gets little respect. That’s why the EPA has declared January to be National Radon Action Month.

Radon is a form of ionizing radiation that comes from decaying uranium and is a known carcinogen. While it is all around us in the air, outside concentrations are diluted below a point of concern. Inside—and particularly in basements or areas where there is limited air circulation—concentrations can reach dangerous levels. Below 2 pCi/L (that’s pico curies per liter of air), risk is minimal. Between 2 and 4 pCi/L corrective action is recommended, above 4 pCi/L calls for professional remediation help.

Slab penetrations can allow radon entry to the living space if not sealed. (Chip Dawson photo)

Radon exposure is the second leading cause of lung cancer (after smoking) and in combination with smoking can have a magnified affect. An estimated 20,000 people get lung cancer annually from radon exposure.

The EPA web site is a treasure trove of information with enough data to fill a science curriculum for a semester and the starting point for this investigation.

So is radon really a problem in North Carolina?

“Yes, it is a problem,” said Mike Lunsford, N.C. Eastern Radon Coordinator with the North Carolina Department of Health and Human Services.

Lunsford

The state radon map shows Mecklenburg County in yellow, meaning the average indoor radon screening level is less than 2 pCi/L—the low potential category. Getting radon much lower than that level is difficult.

“Don’t go by the map”, advises Mr. Lunsford, “there are hot pockets all over. Bedrock and soil types determine where the gas from underground uranium will come to the surface and be a problem. I’ve seen one home with very low radon levels and the home next door will be well over the action level.”

According to Mr. Lunsford, there is no regulatory requirement for testing in homes. However, there is a radon question on the North Carolina real estate disclosure form, so if testing has been done, the results must be disclosed.

RADON IN HOMES

The radon vent pipe on a Cunnane Group home. (Chip Dawson photo)

The ideal situation is to purchase a home that was built with radon in mind, but so far, few builders in North Carolina pay attention to radon. One such builder is the Cunnane Group – if you live in a Cunnane home in Cornelius, the radon work has been done for you.

“We test every home upon completion,” Lance Cunnane, a partner and construction manager for the Cunnane Group, said. “We also install a passive radon remediation venting system in each home. It consists of vented PVC piping installed in the sub-slab stone. The pipe is then run up through the roof after framing. If radon exists over 4 pCi/L we install a blower on the pipe in the attic for added suction.”

The good news, according to Mr. Cunnane, is that no measurement has exceeded 2 pCi/L at the current Antiquity project site (where 155 homes are planned) and no supplemental blower has been required.

TESTING FOR RADON

Testing is easy. Self-test kits can be purchased from the state radon program or from local hardware stores. Ace Hardware, on North Main Street in Cornelius, sells a Pro-Lab 96-hour kit for $11.99. After the sampling container is left in the home for the required amount of time, the kit is sealed and sent to the lab for analysis. Lab cost for the Pro-Lab kit is $30. Details on testing and other options are spelled out on the state web site: www.ncradon.org.

Remediation normally involves sealing ground-level entry points for the gas into the home and providing a system that vacuums the air beneath the slab or basement and exhausts it at roof level.

WANT A TEST?

The state radon site offers a list of certified testers and mitigators, and there are four mitigators in Mecklenburg County.