The equilibrium of attached and unattached radon daughters in the domestic environment.

The Jacobi Room Model is applied to fit radon daughter concentrations measured in a room. The aerosol size distribution and ventilation rate are measured simultaneously. The mean deposition rate fitted to these experiments is 16 h-1. Once all parameters are fixed, the unattached fraction and the effective dose equivalent are calculated, and are put in perspective to the Working Level concept.