METHOD TO MEASURE VOLUME ACTIVITY OF BETA-ACTIVE AEROSOLS Russian patent published in 2015 - IPC G01T1/167 

FIELD: measurement equipment.

SUBSTANCE: invention relates to radiation monitoring of premises and an industrial site, namely to measurement of volume activity of radioactive aerosols. The method is based on sampling of aerosols by pumping air with controlled aerosols via a filtering tape with the specified constant speed, installation of a semiconductor detector above the filtration area and generation of voltage pulses with its help, amplitudes of which are proportionate to energies of α- and β-particles, emitted by particles of the radioactive aerosol that settled on the filter. The filtering tape is moved in discrete mode, settling the taken sample during the time interval sufficient for decay of short-lived radionuclides. In the place of sample settling they install the second semiconductor detector, and using it, they generate a sequence of voltage pulses, amplitudes of which are proportionate to energies of α- and β-particles emitted by particles of the radioactive aerosol deposited on the filter in the place of sample settling, pulses generated on the outlets of each semiconductor detector are selected by amplitude for compliance with radiation of β-active aerosol, using the selected pulses, they determine the volume activity of β-active aerosol during the specified period of time, the full specified period of time T is broken into ℓ time intervals with duration of τ, equal to the specified time of measurement of the current volume activity, at each of these time intervals following each other for each of detectors they calculate the number N_i of selected pulses, where $$i=\overline{\mathrm{1,}\ell }$$ - the number of the current time interval, they determine the current repetition rate of selected pulses (count speed) and current volume activity, at the same time in the place of sampling and settling of samples the detectors are placed in lead protection.

EFFECT: improved accuracy of measurement.