[en] The objective is simultaneous measurements of activities of several beta-samples (up to eight), prepared by methods of radiochemical separation and concentration of yttrium 90 and strontium 90. The spectrometer operation mode of the device allows to use the form and the boundary energy of the beta-spectrum in order to make sure operatively of radiochemical cleanliness of the tested sample. It is used for radioecological monitoring of an environment or control of the contents of strontium 90 in food products and agricultural raw materials. The active surface area of semiconductor detectors of beta-radiation is 400 sq. mm. The minimal power resolution at half-height of peak of the conversion electrons with 624 keV is equal 40 keV. The background intensity in the beta-radiation energy range from 100 up to 2500 keV without the passive shield unit does not exceed 6 pulses/min. Registration efficiency of both yttrium 90 and strontium 90 + yttrium 90 in pelleted samples is not less than 40% and 28% correspondingly. For 30 minutes measurement time and 0,954 confidence level the minimal detected activity of strontium 90 + yttrium 90 in pelleted tests is equal to 0,06 Bq. Radiometer TIM-110 is very reliable and convenient in work. Its loading units are designed for standard bowl used specially for radiochemical samples