Healthier Indoor Air Radon Mitigation Standards Pushed for New Homes Constructed in Minnesota

Rules for mitigating radon gas inside homes constructed in Minnesota are some of the strictest in the nation, but the state Department of Health, concerned the rules don't go far enough, has a new request for builders.

Radon is a naturally occurring, invisible, odorless gas that can be found in soils throughout the United States, including Minnesota. Much like the name suggests, radon is also radioactive. The U.S. Environmental Protection Agency estimates that as many as 800 Minnesotans die each year from radon-induced lung cancer.

Though passive radon vents are already required by Minnesota law, the State Department of Health (MDH) is now asking builders to voluntarily install attic fans that can more actively draw out the toxic gas. So far, only a few builders have signed on to the MDH program. The agency even offers discounts on radon-venting fans to builders if they agree to install them in all of the new homes they build.

Few prospective home buyers are probably thinking about radon poisoning when touring their potential new home. They are more likely to be more concerned about details like hardwood floors and available kitchen storage space. However, a home's radon risk should be of concern, especially for families with children. And though Minnesota's building code is intended to remove some of the burden on homeowners for dealing with radon by requiring all new houses to have a radon-venting pipe, they may not exist in homes built before the code was passed in 2009.

But James Kelly, supervisor of the indoor air program at the health department, says the vents aren't perfect because they rely on the passive movement of air.

"It's like venting a chimney. In some cases your chimney works better than others. Some days, if the wind isn't quite right, you don't get enough draw," he said. "If you add the fan, you're creating a little bit of suction and actually getting pressure in that system to pull the radon from below the slab and vent it safely above the roof."

Despite the health benefits, only eight Twin Cities builders have signed on to the health department's program. It's not an ideal start, but with time builders and consumers will view the extra expense of adding the radon fans as a small price to pay for improving the health of the state's housing stock - and its inhabitants!