What indicates that further radon measurements may be needed after a short-term test?

The correct answer highlights an important consideration in radon testing. After a short-term test, if there is an indication of radon potential, whether through the reading itself or other contextual factors, it often suggests that further investigation is warranted. Short-term tests can provide initial findings, but they may not capture the full picture of a home’s radon levels over time, particularly if conditions such as weather and house occupancy fluctuate.

If the short-term test shows potential for elevated radon levels, it becomes critical to conduct additional testing, such as a long-term test, to achieve a more accurate assessment of radon exposure. Long-term tests typically last for over 90 days and can give a better representation of average radon levels, accounting for variations that might occur during different times of the year or occupancy patterns.

While a clear radon reading below EPA guidelines suggests safety and would not necessitate further testing, and a high reading that requires immediate action would indeed prompt a need for mitigation rather than further measurements, the notion of radon potential signals that the environment may still be conducive to higher radon levels, thereby justifying additional testing for conclusive results. The client's desire for more information, while valid, does not specifically indicate a need for further testing