Concentrations of uranium contained in the front glass of CRT (cathode ray tube) for television sets are measured by two methods: fission track counting and radioactivation analysis. The measurements are also made for other kinds of glass such as a laboratory dish. Systematic errors in the present experiment are shown to be less than about 15% for the uranium concentrations more than 3 ppm from the comparison between the results obtained with these two methods. Moreover, it is presented that the uranium concentrations obtained are 0.4-12ppm for the glass of CRT, whereas they are 0.2-0.7ppm for other kinds of glass. The presence of nuclides of uranium series should be, therefore, taken into account for measuring exactly the radiations near the front glass of CRT.
