Polysulfone membranes containing cerium activated yttrium silicate (CAYS) as a fluor were prepared by the phase inversion technique. CAYS, impregnated in the membranes, worked as the active measuring substance which could detect the amount of radioactivity of beta-emitters. The prepared membranes were used as a wiping medium to monitor radioactive contamination in working areas such as chemical and biological laboratories using radionuclides of beta emitters. In the scintillation assay, the counting efficiency of the membrane wipe test, applied in the absence of a scintillation cocktail, could be close to that of the conventional wipe test that required the presence of the scintillation cocktail. The efficiency in detecting the radioactivity collected by wiping was higher when applied to ¹⁴C-acetylcholine chloride than to ³H-thymidine. The radioactive counting results also revealed that in the wipe test the detecting efficiency was more consequentialthan the pick-up of the detecting efficiency of the prepared membranes, even though the pick-up efficiency was not changed significantly.