Which measurement device utilizes a piece of plastic contained within a detector?

The correct answer is the alpha-track detector (ATD), which utilizes a piece of plastic within its design. This type of detector features a special plastic film that is sensitive to alpha particles emitted by radon gas. When radon decays, it releases alpha particles that interact with the plastic material, creating tracks. Over a specific exposure period, these tracks accumulate and can be counted afterward to quantify the radon levels in the environment.

ATDs are popular for long-term radon testing due to their sensitivity and relatively straightforward analysis process. They are designed to provide accurate measurements of radon over extended periods, which is important in a comprehensive radon measurement strategy. The plastic component is crucial in facilitating the detection of alpha radiation, distinguishing the ATD from other measurement devices that utilize different mechanisms or materials for detecting radon levels.