What is a major source of radon in homes?

What is a major source of radon in homes?

• A. Indoor construction materials
• B. The underlying bedrock
• C. Outdoor air infiltration
• D. Water supply

Answer: (B)

Radon is a radioactive gas produced by the natural decay of uranium in rocks and soil. It moves through the pores in the soil and can seep into homes through cracks and openings in foundations, especially where there is direct contact with the ground. Because it originates from the ground beneath the house, the underlying bedrock is the major source of indoor radon. Building materials can release small amounts, and groundwater can contribute radon if it’s released into indoor air, but these sources are typically much less significant than soil gas entering from the ground. Outdoor air tends to dilute indoor radon rather than create it.

Radon is a radioactive gas produced by the natural decay of uranium in rocks and soil. It moves through the pores in the soil and can seep into homes through cracks and openings in foundations, especially where there is direct contact with the ground. Because it originates from the ground beneath the house, the underlying bedrock is the major source of indoor radon. Building materials can release small amounts, and groundwater can contribute radon if it’s released into indoor air, but these sources are typically much less significant than soil gas entering from the ground. Outdoor air tends to dilute indoor radon rather than create it.