What is a major limitation of short-term tests regarding radon measurement?

Short-term tests for radon measurement typically last from a few days to a week, making them particularly useful for quickly assessing radon levels in a specific area. However, a significant limitation of these tests is that they are less likely to accurately reflect year-round averages of radon concentrations.

Radon levels can fluctuate based on various factors, including seasonal changes in temperature, humidity, and air pressure, as well as variations in ventilation and building usage. Short-term tests may capture only a snapshot of radon levels during the testing period, which can lead to misleading results if that timeframe does not represent the radon levels for the entire year.

In contrast, long-term tests, which last for several months to a year, are better suited for providing a more accurate representation of average radon levels over time. This distinction makes it clear that relying solely on short-term testing may not give a comprehensive understanding of a home's radon exposure risk throughout the year.