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In some countries,by-products (slags,ashes,etc) of NORM processing are used for building materials.Those building materials could be significant sources of indoor radon and thoron.Accurate knowledge of the exhalation rate of radon and thoron plays an important role in characterization of the radon/thoron source strength in building materials.The aim of this work was to compare of four different methods to measure radon/thoron exhalation rates for building materials: 1) etch-track,2) electret,3) electrostatic monitor with accumulation chamber with passive mode and 4) accumulation chamber with a solid-state alpha detector in flow mode.Sixteen building materials samples were used for comparison.In addition,all of these methods were calibrated using NIRS radon and thoron chambers.This work summarizes advantages and disadvantages of different methods as well as presents obtained results.In example,the electrostatic monitor and the alpha detector methods are relatively fast (one day) but their efficiency highly affected by the humidity.The electret method is also fast (few hours) but discrimination of radon and thoron from sample is not possible.Results obtained by etch-track detectors are reliable but this is time consuming method and detectors should be exposed longer than one month.