Defined solid angle absolute β-counting for use in the radioanalysis of environmental samples

Defined solid angle absolute β-counting (DSAABC) of thin samples using an end-window Geiger-Müller counter is shown to be a useful auxiliary method in some fields of environmental radioanalysis. Correction factors are used in the DSAABC method to account for the numerous effects responsible for losses and gains in the β-counting rate. A few new proposals are made in connection with the possiblities of the reduction and evaluation of the above factors on the basis of the comprehensive review of the literature. New formulas are proposed in order to evaluate correction factors for backscattering and internal backscattering. The case of the exponential decrease of activity as function of the depth in filter sample is treated separately. The most important experiences related to the use of the DSAABC method in three practical applications are presented.