Unattached fraction deposition rate

In Figure 9 it is shown that the attachment rate is the dominating factor for the unattached fraction. The equilibrium factor however, is also strongly influenced by the deposition rate of the unattached daughters. The curves are calculated as in Figure 7. The limited fluctuations of the actual data illustrate the importance of the attachment rate. 

The primary route of exposure to radon and its progeny is inhalation. The degree of deposition and the subsequent absorption of inhaled radon and progeny is determined by physiological parameters, such as respiration rate and tidal volume and physical properties, such as the particle size distribution of the carrier aerosols and of the unattached fraction, the equilibrium state, and solubility coefficients (Crawford-Brown 1987 Holleman et al. 1969 Jacobi 1964). 

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