Radon is the second leading cause of lung cancer in the United States, causing 20,000 deaths each year according to the National Academy of Sciences.. The Surgeon General, and the Environmental Protection Agency both urge people to test their homes and reduce elevated radon concentrations. Monitoring in east-central Tennessee identified dramatic temporal variability in radon concentrations within individual homes. This variability seemed related to differences between ground and outdoor air temperatures, and the ability of these temperature differences to move air through caves and channels of the underlying karst geology. This air movement can alternately infuse the soils around a building with radon laden air from the earth, or flush those soils when "clean" outdoor air is drawn into the karst system. Changing the concentration of radon in the soil gas surrounding a building can dramatically change the indoor radon levels in a matter of hours. Short-term radon measurements are not reliable indicators of the long term radon concentration in buildings in karst areas. Recognizing this, the States of Kentucky, Alabama, and Tennessee, the Southern Regional Radon Training Center, and the US Environmental Protection Agency met to review EPA's indoor radon testing procedure in karst areas. A consensus new testing procedure was developed that recommends 12-month testing in karst areas of those states, warns against using shorter term testing, and calls for periodic retesting. Similar situations have since been identified in both Canada and Europe.
Learning Objectives: Learning Objectives At the conclusion of the session, the participant will be able to: 1. Describe the potential effect of karst geology on indoor radon concentrations 2. Articulate the indoor radon testing protocol for karst areas of Kentucky, Tennessee, and Alabama. Teaching Objectives During the session, the presenter will discuss: 1. Karst geology 2. Indoor radon data from karst areas 3. A long-term radon testing procedure for karst areas
Keywords: Indoor Environment, Air Quality
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: The work of the Southern Regional Radon Training Center (SRRTC) will be discussed in the paper. I am head of a section within the USEPA that has funded the SRRTC to carry out portions of the work discussed in the paper.
I have a significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.
Relationship: EPA has provided the Southern Regional Radon Training Center funding to support work that is described in this paper.