الفهرس 
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Abstract
Based on the experimental results of the activity size distribution of attached short lived radon progeny (214Pb and 214Bi), simulation of lung dosimetry has been achieved by using the ICRP66 [1994] dosimetric model.
The analysis and discussions of the results permit us to drawing the following conclusions:
1. The activity size distribution parameters (AMAD and GSD) of attached short lived radon progeny (214Pb and 214Bi) are nearly identical.
2. Active Median Aerodynamic Diameter, AMAD, of attached 214Pb was found to be 416.8 nm with corresponding Geometric Stander Deviation, GSD, of 3.47
3. Active Median Aerodynamic Diameter, AMAD, of attached 214Bi was found to be 407.58 nm with corresponding Geometric Stander Deviation, GSD, of 3.46
4. Most of the derived activity size distributions could be approximated as unimodal log–normal distributions represented by the accumulation mode (100 nm ≤ aerosol particle size ≥ 2000 nm). Very small activities are found in the coarse mode (aerosol size range ≤ 2000 nm).
5. In the case of nose breathing, the deposition fraction of attached particles (214Pb and 214Bi) were change in the same manner during their passing through ET1, ET2, BB, bb and Al regions of the respiratory tract.
6. Also, in the case of mouth breathing, the deposition fractions of attached particles (214Pb and 214Bi) were change in the same manner.
7. For nose and mouth breathing, the deposition fraction is lower in the bronchi and increases with succeeding bifurcations of the human respiratory airways.
8. In the case of nasal breathing for (214Pb and 214Bi), the total fraction of deposition were increase from sleep to sitting to light exercise then decrease in heavy exercise.
9. In the case of mouth breathing for (214Pb and 214Bi), the total deposition fraction were increase from sleep to sitting then decrease in light exercise and heavy exercise.
10. Finally, it was found that the effective dose for 214Pb is 0.2 mSv/y and for 214Bi is 0.25 mSv/y.
11. The present value is lower than the recommended value (1mSv) according to world health organization (WHO, 1993), United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000) and International Commission on Radiological protection (ICRP, 128) for public exposure.