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RadTown Radon Activity 1: Ground Up

Radon Activity

Radon Image

In the Ground Up activity, students have the opportunity to learn about soil permeability and how radon moves through Earth’s crust, into homes and buildings. Using critical thinking skills, students have the opportunity to make decisions about radon readings in two homes. A lab activity gives students the ability to observe effects of different inputs in a system. This activity is intended for middle and high school students.

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Students will:

  • Predict whether they live in an area where the potential average indoor radon levels are low, moderate or high.
  • Investigate why indoor radon levels vary.
  • Conduct experiments to investigate the movement of radon through the ground.

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Next Generation Science Standards

The concepts in this activity can be used to support the following science standards:

  • ESS2. Earth’s Systems
  • ESS3. Earth and Human Activity

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Materials and Resources

Each italicized document title can be found at the bottom of this page, and is available for printing and distribution.

  • Radon: Teacher Background Information
  • Vocabulary Materials
  • Radon Zones Map and state radon zones map (display with computer and projector, copy for students, or allow them to access the maps with student computers):
  • Ground Up Worksheet (one per student, pair or group) and Ground Up: Teacher Answer Key
  • Ground Up Data Sheet (one per student, pair or group)
  • Containers, such as small, clear plastic tubs or clear plastic cups (at least one per pair or group or one for each type of rock and soil per pair or group)
  • Rocks and soil representative of the local geology (enough of each type so pairs or groups can partially fill the tubs or cups)
  • Straws (at least one per student)
  • Beakers (one per pair or group)
  • Water
  • Droppers (one per pair or group)

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45-60 minutes, not including optional activities or extensions.

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  • Ionizing radiation
  • Radiation
  • Radioactive atom
  • Radioactive decay
  • Radon
  • Uranium

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  1. Start with a vocabulary activity if students are not familiar with radon and the vocabulary words used in this activity.
  2. Explain that radon is a naturally occurring radioactive gas that comes from the decay of uranium found in rocks and soils. Human activities, such as uranium mining, can increase the risk of radon exposure. During the mid-1940s to 1970s, the U.S. was in a race with the Soviet Union to develop and test nuclear weapons. Nuclear power was also introduced during this time. Thousands of uranium mines were in operation, primarily in the Western part of the U.S., and nuclear testing was taking place in the West and in Alaska. When the demand for uranium decreased, uranium mines and testing areas were abandoned; leaving contaminated soil and water with high radon levels that has affected disproportionately Native Americans and Alaska Natives.

    Radon is a threat to health because it tends to collect indoors in homes and buildings, sometimes to very high levels, and can cause lung cancer.
  3. Ask students to predict whether they live in an area where the potential average indoor radon levels are low, moderate or high and explain their reasoning.
  4. Display or provide students with a copy of the Radon Zones Map and their state map. State maps are web-accessible through Local Radon Zones and State Contact Information. Explain that the maps show potential average indoor radon levels by three zones: Zone 1 (red) is predicted to have high indoor radon levels, Zone 2 (orange) moderate indoor radon levels, and Zone 3 (yellow) low indoor radon levels.
  5. Ask students to hypothesize why certain areas (or the area where they live) have greater potential for higher indoor radon levels or why two houses side by side can have very different radon levels. This is due to the geology below the individual homes. It may be that the rock and soil has a higher uranium (and therefore, radon) content or that the type of rock and soil and presence of cracks and fissures that might allow radon to move up more easily through the ground. How well the homes are built, including how well floors, walls and gaps are sealed or how ventilated the home is, may be other factors.
  6. Distribute the Ground Up Worksheet. Provide rock and soil samples of the local geology and identify each. Direct students to answer the questions.
  7. Distribute the Ground Up Data Sheet. Direct students in completing the experiments and documenting their findings.
  8. Review students’ findings and conclusions when complete. The Ground Up: Teacher Answer Key may serve as a guide.
  9. Conclude by asking students if they should rely solely on radon maps to determine whether they should test their home for radon. Students should recognize the importance of testing all homes because uranium exists in nearly all rock and soil and the movement of radon can vary greatly based on the formation of the earth or the presence of cracks and fissures below individual homes.
  10. Optional activities or extensions: Have students:
    • Investigate how scientists collect soil air samples to determine the radon content.
    • Investigate local soil air data (check with your state’s radon program), chart the data and identify areas of concern.
    • Examine the local rock and soil types. Plot on a map the geological breakdown of the area with low, medium and high radon potential. Have students test different areas using short-term test kits. Plot the results on the map, determine which results correlate with the radon potential of area and provide possible explanations if the data doesn’t correlate.

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Common Core State Standards (CCSS)

The concepts in the Ground Up activity align with the following:

  • CCSS English Language Arts Standards for Literacy in History/Social Studies, Science, & Technical Subjects.
    • CCSS.ELA-LITERACY.SL.6-12.2 Comprehension and Collaboration
    • CCSS.ELA-LITERACY.WHST.6-12.1 Text Types and Purposes
    • CCSS.ELA-LITERACY.WHST.6-12.9 Research to Build and Present Knowledge

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Printable Worksheets and Classroom Aids

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