Deposition of fibers in human lungs is known as a health hazard. In-vitro measurements were performed with glass fibers in a realistic model of human lungs up to the seventh generation of branching to estimate the effect of fiber size and breathing pattern on fiber deposition. Deposited fibers were rinsed from the model segments and gathered on nitrocellulose filters. Phase-contrast microscopy with high resolution camera was used to capture images of filters with fibers. New software was developed for an automated image analysis and local deposition characteristics were calculated afterwards. The whole method proved to be a useful and valuable tool for the evaluation of fiber and particle deposition. and Obsahuje seznam literatury