How do charcoal liquid scintillation devices measure radon?

Charcoal liquid scintillation devices measure radon by analyzing the alpha and beta particles emitted during the decay of radon and its decay products, also known as radon decay products (RDPs). When radon gas is absorbed by the charcoal, it undergoes radioactive decay, releasing alpha particles. These alpha particles cause the surrounding liquid scintillation material to emit flashes of light, which are then detected by a photomultiplier tube. The intensity of the light corresponds to the amount of radon present, allowing for a quantifiable measurement.

This method is specific to the detection of ionizing radiation emitted during the decay of radon, making it a direct and effective way to quantify radon levels in the environment. The other options focus on unrelated phenomena; gamma radiation detection is not the primary mechanism in this context, and humidity and temperature variations do not measure radon levels directly. Therefore, the method employed by charcoal liquid scintillation devices is distinctly focused on the characteristics of alpha and beta particles resulting from radon decay.