Radon – invisible but deadly

The U.S. Environmental Protection Agency rates radon, a radioactive, colorless, odorless and tasteless gas, as the second leading cause of lung cancer in the United States; responsible for about 20,000 deaths a year.Radon is the natural byproduct of decaying uranium, which is abundant in Colorado soils. Most Colorado counties are ranked in the zone having the highest radon potential.Radon seeps into buildings through cracks in foundations and accumulates, especially during the winter months when windows and doors are closed, said Warren Smith, community involvement manager for the Hazardous Materials and Waste Management Division of the Colorado Department of Public Heath and Environment.”The only way to know that you have radon is to test for it,” Smith said, and the best time to test is during winter when people keep their doors and winters closed.To have someone test for radon costs $80 to $100, said Falcon real estate agent Mitchell Baldwin.The test involves leaving a canister inside the building for several days and then taking the canister to the University of Colorado in Colorado Springs to have it tested, he said.In his experience, younger home buyers tend to be more concerned than older buyers about a home’s potential for radon, Baldwin said. “A lot of them don’t want to spend money to do the test,” he added.Homeowners can perform the test with less expense, Smith said. The Colorado Department of Health and Environment has coupons for test kits from Kansas State University available on its Web site, www.cdphe.state.co.us/hm/rad/radon.The $15 coupon purchases a short-term test kit (for determining whether radon is a problem) and the $25 coupon purchases the long-term test kit designed to most accurately determine the amount of radon that accumulates in a building.Or homeowners can purchase test kits or their own electronic radon monitor, much like a carbon monoxide monitor, from online retailers. Test kits are available for less than $13 and a full-time electronic monitor for $130.In the United States, radon is measured in pica curies per liter of air. Until recently, a reading of 4 pC/L or higher was cause for concern, but in September the World Health Organization called for tighter standards.A press release at the WHO Web site, www.who.int, reports that, in the past, scientists assessed lung cancer risk from radon by studying uranium miners, but “new studies in Europe, North America and China … confirmed that low and medium level exposures to radon in homes contributes substantially to the occurrence of lung cancers worldwide.”Studies show that radon is the primary cause of lung cancer among people who have never smoked. However, the absolute numbers of radon-induced lung cancers are much larger in people who smoke, or who have smoked in the past, due to a strong combined effect of smoking and radon.”Baldwin estimated that 50 percent of homes in the Colorado Springs area have radon levels high enough to require mitigation.The state does not require the installation of mitigation systems when a house is built because building codes are usually local and Colorado is a home rule state, Smith said.To Smith’s knowledge, Ft. Collins is the only Colorado municipality requiring the installation of a mitigation system when a house is built.Jim Vernon, heating and ventilating inspector for the Pikes Peak Regional Building Department, said they have not considered mandating a mitigation system. Currently, the PPRD does not require a homeowner or a contractor to get a permit before installing a radon mitigation system, but the PPRBD is considering requiring a permit when it adopts the 2009 International Building Code as early as 2011, Vernon said.The PPRBD is also considering requiring radon mitigation contractors to register with the building department. Currently, contractors are only required to be licensed by the state, he said.According to an article by housing specialist K. R. Temblay Jr. posted at www.ext.colostate.edu, installing a radon mitigation system during construction costs between $350 and $500 and from $1,200 to $2,500 after construction.Temblay writes that sub-slab depressurization is the most commonly used and effective radon mitigation technique.The system consists of pipes laid in gravel under the basement floor. Holes in the pipes allow the radon to enter the system, and a vertical pipe, typically hidden in a closet, vents the gas out above the roof. The system may also require a fan to provide the required suction to lower the radon level below 4 pC/L.In his book, “Protecting Your Home from Radon,” Colorado Springs resident Doug Kladder describes how to use an existing exterior foundation drain to mitigate radon.If a mitigation system can’t be installed, Temblay suggests the following:

• When possible, keep windows open on both sides of a house’s lower floor.
• Ventilate crawlspaces.
• Open basement windows early in the spring and, when possible, keep them open until late fall.
• Seal cracks in basement floors with polyurethane caulking compound.
• Pour water in floor drains once a month to make certain the traps don’t dry out.
• Keep stairwell doors, fireplace dampers and laundry chute doors closed to prevent air from the basement from being sucked into the house’s living area.

“Radon is something where people actually have an opportunity to take control of an environmental hazard,” Smith said. He said his department has received the first application in 25 years for a uranium-processing mill near Naturita, Colo., and more applications are expected.”A lot of people are very upset about the prospect of living next to a source of radiation like this,” he said. “But radon is much more pervasive, and radon presents an opportunity for you to take active steps to reduce your exposure to environmental radiation and actually take your health risks into your own hands.”