Browsing by Author "Zihon, Gizachew"

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Attached and Unattached Fraction of Radon Decay Products in Mine Atmosphere
    (Addis Ababa University, 2010-06) Zihon, Gizachew; Tesfaye, Tilahun (PhD)
    In this work it is analyzed that radon daughters are produced as free ions, but they become attached to aerosol particles at a rate depending on the aerosol concentration. Most of the attached activities for Rn-222 progeny were associated with aerosol particles of the accumulation mode. Various parameters influencing the concentration of the radon daughter products in the atmosphere of dwellings are reviewed. Risk factors for lung cancer from the inhalation of attached and unattached radon decay products are indicated. Methods for controlling excessive radon exposures in mine atmosphere, indoor, and outdoor are outlined. The activity concentration of radon daughters and thoron daughters and also plot of the amounts of particles with time are discussed