Which type of Activated Charcoal Device (ACD) allows radon to adsorb directly into the charcoal?

Activated Charcoal Devices (ACDs) play a crucial role in measuring radon levels due to the properties of activated charcoal to adsorb radon gas. The open-faced design is particularly effective because it allows radon to adsorb directly into the charcoal without any obstructions. This direct exposure enables the charcoal to capture radon molecules more efficiently, which is essential for accurate radon measurement.

In contrast, other designs, such as closed-faced devices, have barriers that can limit the flow of radon gas to the charcoal and potentially lead to inaccurate readings. Therefore, the open-faced activated charcoal device is the most suitable option for directly capturing radon, as it maximizes the surface area of the charcoal exposed to the air and allows for better adsorption of radon. This design is crucial for obtaining reliable radon measurement data, contributing to effective assessment and mitigation efforts.