Making mitigation decisions based on short-term tests of 222Rn

Area of Science:

• Environmental Science
• Public Health
• Building Science

Background:

• Radon testing is crucial for indoor air quality.
• The Environmental Protection Agency (EPA) provides guidelines for radon mitigation.
• Accurate radon measurement is essential for public health protection.

Purpose of the Study:

• To evaluate the frequency of errors in radon mitigation decisions using a specific EPA-recommended test option.
• To assess the reliability of a two-measurement radon testing protocol.
• To quantify the chances of incorrect mitigation decisions in residential buildings.

Main Methods:

• Analysis of 2-day and 1-year radon measurements from 1,449 houses.
• Evaluation of an EPA-recommended test option involving up to two short-term radon measurements.
• Calculation of error frequencies based on a mitigation threshold of 148 Bq m-3.

Main Results:

• The frequency of incorrect mitigation decisions varied widely, from 1% to over 50%.
• The two-measurement test option, while intended to improve accuracy, demonstrated a high potential for decision errors.
• The study highlighted significant variability in the reliability of the EPA's recommended radon testing protocol.

Conclusions:

• The EPA's two-short-term measurement protocol for radon mitigation decisions is associated with a substantial risk of errors.
• Homeowners and professionals should be aware of the potential inaccuracies when using this testing method.
• Further research may be needed to refine radon testing protocols for more reliable mitigation decisions.