Which detector is deployed for long-term radon measurement?

The Alpha Track Detector is designed for long-term radon measurement, making it the correct choice for this question. This type of detector works by capturing alpha particles emitted from radon decay over an extended period, typically several months to a year. The detector consists of a plastic film that becomes damaged by the alpha particles, and the amount of damage can be analyzed to determine the average radon concentration over the measurement period.

Long-term measurements are crucial for effectively assessing radon exposure risks in homes and buildings, as they provide a more accurate representation of radon levels that can vary over time due to factors such as weather changes and building occupancy.

In contrast, the Electret Ion Chamber and Activated Charcoal Test are generally more suited for short-term measurements. The Electret Ion Chamber utilizes a charged electret that can detect radon levels over a period of days to weeks, while the Activated Charcoal Test primarily captures radon over a few days. The Liquid Scintillation Detector, although capable of detecting radon, is not commonly used for standard long-term radon measurements in homes. These other detectors typically do not offer the same level of comprehensive data needed for understanding prolonged exposure to radon.