Which of the following describes a characteristic of alpha track detectors?

Alpha track detectors are designed specifically for measuring long-term radon levels in the environment. They function by collecting alpha particles emitted by radon decay over an extended period, typically several months. The detector contains a special film that records the tracks of these alpha particles. After the exposure period, the film is chemically processed to reveal the number of tracks, which correlates to the concentration of radon gas in the air.

The emphasis on long-term measurement is crucial for assessing radon exposure because radon levels can fluctuate significantly over short periods due to variations in weather, ventilation, or other factors. By using alpha track detectors for prolonged exposure, a more accurate average radon level can be established, providing valuable data for evaluation and remediation if necessary. This characteristic is essential for both homeowners and professionals in ensuring safe indoor air quality.

In contrast, options that suggest measuring air pressure changes, requiring a power supply, or being unable to detect radon gas do not align with the fundamental functioning and purpose of alpha track detectors.